# OK.....Let's Get Into The Meat Of SRT !!!!



## rahtreelimbs (Dec 29, 2003)

Now that SRT seems to be the current big topic at hand. I am curiuos about a few things. I've known about SRT for about 5-6 yrs. now. I used it to clear a hillside once but never fully in a tree. The thing that I don't like is that your hitch bites down twice as hard as compared to double-rope. For the moment let's keep mechanical devices out of this and concentrate on hitches. Is there a hitch that releases easily on SRT?


Also tying off at the ground seems to be chancey. Keeping the limbs out of the rope tied at the base seems hard.


The floor is now open!!!


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## Tom Dunlap (Dec 29, 2003)

I've never even considered using a hitch for just that reason. I'll bet that with some experimenting a rope/cord/hitch could be found that would grab and slide easily.

If I were to start an experiment I would probably start by adding a whole bunch of round turns to the top of a distel. Since its the upper loops that grab, it would seem that a combo could be found. Add a slack tender and it might work. 

Tom


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## rahtreelimbs (Dec 29, 2003)

Tom, I am glad you replied. Do you use SRT exclusively now. If not, what circumstances have you found double-rope to be better?


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## MasterBlaster (Dec 29, 2003)

> _Originally posted by Rich Hoffman _
> *... what circumstances have you found double-rope to be better? *




Uhhhh, 'bout all of 'em? :angel: 

'Course, I ain't Tom! He's an SRT wildman! Er, him 'n Carl...


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## rahtreelimbs (Dec 29, 2003)

MB, I am not about to give up DbRT just yet. I just want to see what all the hype is. If I can't use a hitch of some sort, then I may not even consider SRT.


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## Lumberjack (Dec 29, 2003)

I have found that on my Blue Steak, if I use a 1/2" rope for the tress cord, it helps alot. 

On when DbRT works better is when I am comming down a spar partially and need to retie in. I put the rope over a stub, and come down with the rope doubled over. That way when I get to where I need to be, I can pull my line back down and reattach the line normally.

On stuff getting caught up in line that is returning to the base, I have never had that problem. I make sure that the returning rope is very close to the trunk. Now that I have my 200, I can pull the rope outa the way when flushing up after cutting a limb no problem.


I like the Idea of having the gri gri at the base, but I have not used it, mostly because I don't have a Gri Gri, but you could use a terrible hard locked 8, and get the same effect.


Not that yall care, but other than stated above, I use SRT exclusively. I started out with it, and have been using it for the whopping 4 months now (seems alot longer). The reason why is because I didn't like the problems asociated with isolating a TIP on DbRT, it was simpler, and it was what I knew. I would look at the pics in Sherrill and see that they pics used DbRT, and I couldn't figure out why, because my way was doin fine. I investigated (here and other places) and figured that I would stick with my method, because it was easier and simpler.

Matter of fact, when I first started with that god awful swiss seat, I had an ascender (closed shell I don't like handled), and a loop of rope I bought from low's to tie down the trailer. Boy have I come a way since then.


Carl


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## MasterBlaster (Dec 29, 2003)

> _Originally posted by Rich Hoffman _
> * I just want to see what all the hype is. *





The key word is 'hype'. 

Can 'ya dig it?


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## Lumberjack (Dec 29, 2003)

> _Originally posted by MasterBlaster _
> *The key word is 'hype'.
> 
> Can 'ya dig it?  *



Common Butch, even you can open up a little. What about the automatic tunner you showed me. Seems crazy, but it helps wonders. Change can be for the better. You know I wouldn't do it if it wasn't the best thing since sliced bread.


Carl


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## John Paul Sanborn (Dec 29, 2003)

It's another set of tools to keep in the bag. There is a big learning curve in working SRT, so many who try it dont like it enough to not use it at all.

I can see someone who makes their money based on their current level of profficiency not wanting to even try it.


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## NickfromWI (Dec 29, 2003)

> _Originally posted by Rich Hoffman _
> * Is there a hitch that releases easily on SRT?
> *



With a little experimentation you can find one. I did and others have as well. Here are my tips for finding that works for you.

Use something that has as high of a heat resistance that you can afford. Technora and Vectran are both good. Nomex also works (though I hear that depending of the construction of the rope, Nomex lines can have LATERAL stretch, which will greatly affect how the hitch grabs and releases). Larger diameter cords are less likely to bite down so tight that you can't release. Like Tom mentioned, a knot with more twists and turns that what you are used to will distribute the load over a greater surface area. This means that each part of the hitch is holding less weight (though the overall is the same, obviously). With each part not holding on as tight, it will still be releasable.

I think that's it for now. I'm sure there's more. You just gotta play with it. That being said, I think that SRT will be most successful when someone comes out with a mechanical device that can be advanced in the same way one would advance a Distel with a slack tender pulley. Like a lock-jack for srt.

love
nick


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## Hemlock (Dec 29, 2003)

I have wrapped a locking biner with a lanyard to a single line. It's easy to advance and holds good. I run the loop around two or three times from the bottom up and clip the bight into the top of the biner. the other end goes on the harness. Nothing is hooked into the biner, it just rides between the coils and the climbing line to make it slide easier.


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## Lumberjack (Dec 29, 2003)

> _Originally posted by Hemlock _
> *I have wrapped a locking biner with a lanyard to a single line. It's easy to advance and holds good. I run the loop around two or three times from the bottom up and clip the bight into the top of the biner. the other end goes on the harness. Nothing is hooked into the biner, it just rides between the coils and the climbing line to make it slide easier. *




You are refering to a knot called the bachman i think. I have never tried it, but I bet it would work fairly well. I have a picture, gotta get it on the computer.

Carl


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## Lumberjack (Dec 29, 2003)

Here it is.









Carl


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## Tree Machine (Dec 29, 2003)

I use SRT most of a climb these days. That sounds odd. Try this: During a climb, most of the time I spend on rope is SRT.

Someone (I think it was Lumberjack) mentioned this in a previous thread; It went something like, tying off the standing end of your rope, not to the base of the tree, but rather, up IN the tree.

Just because it's faster for me, I DdRT up the tree, anchor the standing end of the rope up in the tree, SRT while I work the crown, and rappel out DdRT; unless I'm coming down with the intent of going back up, then I SRT down and SRT back up, and the final rappel DdRT. This is likely to change again as there's always new techniques to try, but that's been my general way since last Spring. 

Maybe it's because it was a good number of years before I gained a true appreciation of SRT that I still DdRT a bit. Maybe it's because for me, switching from SRT to DdRT is like switching from tangerine to orange. Same sorta flavor, different sorta fruit.

Since I don't use friction hitches, except here in my basement to keep fresh in knowing how to do them, I'm going to step back out of this thread, which requests SRT concentrating on hitches. PS thanks for all the friction hitch threads lately. I find them fascinating. 

Lumberjack, thanks for that pic. I honestly haven't seen that one before. -TM-


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## NickfromWI (Dec 29, 2003)

Carl, I found that knot a few years ago. It sure looks cool! I tried it out, but not extensively. You cannot descend on it, can you? I didn't think to try. I assumed it was like the prusik.

love
nick


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## Lumberjack (Dec 29, 2003)

> _Originally posted by NickfromWI _
> *Carl, I found that knot a few years ago. It sure looks cool! I tried it out, but not extensively. You cannot descend on it, can you? I didn't think to try. I assumed it was like the prusik.
> 
> love
> nick *



I dunno, I have never tried it, but with the givin description of the knot, I think that it may by for accending only, but who knows? Hemlock?



Carl


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## Hemlock (Dec 30, 2003)

Carl you hit the nail on the head. I would only trust it for ascending since there are alot of other ways to descend. I just happened upon it while buying some gear one day. The rock climbers I talked with sure liked it for what they use it for. I still feel a little uncomfortable with one rope as I don't climb that much anymore. I'll tell you what though, seeing pictures of MB swinging around up there sure makes me want to get up there too!


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## Lumberjack (Dec 30, 2003)

Tree Co raises a good point. I have never thought about it, but I am always tied in twice when I am running the chainsaw. That would make it awful hard to lower me when I am hurt.


On the note about something getting caught up in the line that returns to the base, I have never had anything get caught up in the line. I always make sure that the rope is as close to the trunk as posible, on the limb and then down the backside of the trunk. I wouln't want to cut a limb that was holding my climbiing line away from the trunk, as I would fall, as the slack was taken up, and I would land on my lanyard. That is why I make sure that it runs along the trunk. The only drawback to that is when you are flushing a cut, and you hafta pull the return line off the limb. That isn't a problem anymore now that I have my 200.

That being said, I could see how on a sprawling canopy the return line could get away from the spar, but a coupla redirects would take care of that. 



Carl


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## Tom Dunlap (Dec 30, 2003)

First off...

MB,

Unless you have something constructive to add to this thread, pipe down. I think we all know what your feelings are about SRT. I'm getting really weary of your sniping every time SRT comes up. This is what I'm referring to when I talk about civility. If you're just trying to up your message count, why not do it in another thread or forum.

Now, onto the subject at hand.

There isn't a lot that I can add to what has been said. The concerns that've been raised are valid. I like the oranges and tangerines analogy. 

SRT has been a progression for me. Starting with choking my climbing rope with a running bowline to my TIP. As I moved along I realized that this had limitations. My goal has been to push SRT along and eliminate or reduce any limitations. 

Like others have said, using it for ascent first and then gradually start to use it for working will lead to more use. I think that more climbers would use SRT if they were like Carl. Starting with a fresh plate and no bias towards either DdRT or SRT I think that an open-minded climber would tend to SRT. This is a nature or nurture test. Maybe I can get a grant to study this 

Any friction system can be used at the base. Heck, a Munter works fine. I use a Gri Gri because I think it solves the problem better than any other device, that's all. IF there is a concern that the anchor might be bumped, the line can be redirected out the other side of the TIP and down to another anchor point. I always hard lock the line over the top of the Gri Gri.

Nick gave some good focus to finding a different climbing hitch. I'm sure there's one out there. I didn't go that route because I like the performance of the tools. I could see taking a side step and seeing what comes up though. Too bad I'm not climbing a lot this time of year. 

If a rescue is needed, sure, an SRT climber with a lanyard would still need a climber to come up. But, if they were able to unlanyard themselves, the rescue could then be groundbased. If not, the patient is in no worse shape than a DdRT climber. Actually, a rescue might be a little easier having the patient in SRT. If there were a third, the climber would be able to just control the movement of the patient and the groundie would take over the lowering. This would take a lot of the jostling out of the rescue. Frees up the rescue climber to do other things besides tend to a climbing hitch.

Keep tossing things out here. You guys are coming up with some nuances that I movec past or haven't considered because of my thought processing.

Tom


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## MasterBlaster (Dec 30, 2003)

Sorry if the 25 words I've posted earlier got yur undies in a bunch. I'll leave you alone on yur pulpit.

My pipes are down.


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## MasterBlaster (Dec 30, 2003)

I would say I'm kinda like a mirror, but my pipes are down....


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## John Paul Sanborn (Dec 30, 2003)

I don't think it is a lack of respect with most people. It is that when we are new to this we don't realize that the words are the only thing that comes across and cann be interpreted differently then we intended. 

There are not those indicators of tone and body that we use while face to face that allows what we intend as a jocular comment to be interpreted as petty jab.

As Tom has often pointed out, petty remarks go away when ignored. Responding in kind will lead to the obnoxiouse tit for tat things we can get.

If people would take a moment and look at critical remamrks and ask, "How would i react to this towards me?" we would have a lot less of this.

Though this would not work on Butch, he just laughs it all off  

SO to wind things down, We what we would like to see is constructive critisism and less posting that boil down to "B-S!"


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## rahtreelimbs (Dec 30, 2003)

Moving on.

Tom, working any tree where the movements are up and down, do you find body thrusting several feet difficult? On DbRT half of your weight is displaced at you TIP, so you are only pulling 1/2 of your weight. Also, when body thrusting DbRT you are actually pulling yourself up, whereas with SRT you are pulling yourself like climbing a firepole. How did you address this? Thanx, Rich.


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## NickfromWI (Dec 30, 2003)

Tom, you raised a good point about the rescue. If you were lanyarded in, and became disabled, I could footlock up to you on your own line, let a bit of slack into your flipline, then Butch could lower us to the ground. That's super quick!

love
nick


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## Tom Dunlap (Dec 30, 2003)

Rich,

If there is an Achilles heal in working SRT, you hit it. Moving up using an I'd isn't easy. The first part of the solution is to plan several moves ahead. IN SRT it requires that the climber do more planning. If not, the gains will be lost by having to move up.

When I do have to move up a free hanging rope I use some variation on RADS:

http://www.rescueresponse.com/html/news02-02/highlight.html

The next time I climb I'll be using a Wild Country Hand for the upper ascender and then I'll clip in a plain oval biner into the eye. Petzl makes an orange plastic sheave that's meant to make a simple pulley. The reason I'm planning on using this setup is that it is really compact. When I played with it in the garage, the Hand moved up really smooth. Look on Storrrick's site to see what a Hand looks like. They're not made anymore though.

Setting up the RADS does pay off though. If I set it up and leave it in place it becomes a floating false crotch of sorts. I'll leave it in place if I plan no doing several yo yos. I suppose I could use a throwline for a retriever if I didn't want to go back up to get the RADS.

Understand that the RADS uses up another long chunk of rope. If you don't plan ahead you could run out of rope when you get low in the tree. That would mean labandoning the RADS or going back up to retrieve. To get around this, I bring it down as I work the canopy {I sure do like typing that  ] down in layers.

Tom


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## Lumberjack (Dec 30, 2003)

I tried out my i'D today, and I must say that I like it. It was a small rec climb, no working, but it was fun.


After a minimal amount of thought, here is what I came up with for my Rads (does that stand for something?), using stuff I already had. It has a 3:1, and for people that normally do DbRT, it should be easier because of the 3:1, and more natural. I bodythrusted up the tree several times, and it wasn't nere as fast as SRT, but if you had a good groundie, you might be able to get as fast or faster than SRT, once you get the rythm. It will make yo-yoing much easier. I tried it with the Pantin, but didn't like that. Tomorrow I might try footlocking, as that would probably be the fastest.


I like the setup very well, and it will become my normal setup. If your rope was long enough, you could come down for lunch (in a huge tree, or if you started late) and go back up almost as easy as an elevator, if you had a groundie, it would be awsome.


Here is the pic.





Carl


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## Tom Dunlap (Dec 30, 2003)

RADS

R-***
A-ascending
D-escending
S-sytem

That looks nice! 

Tom


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## Tree Machine (Dec 30, 2003)

*Simplify*

Guys, I have to say my head spins when I read all your stuff. I've been doing SRT since I came into this profession 10 years ago. I've done SRT all kinds of different ways, different nuances of established technique, different rope diameters, a variety of devices. I have never gone up using a RAD system. A variation of it going down, yes, occasionally.

Rich mentions body thrusting. I thought that was a technique you use in a pinch, like when the rope you're about to ascend is 5 feet off the ground, you body thrust until you've got rope at your feet.  

I see you guys trying to set up ascent systems using descent / belay devices. That's novel, I will admit, but still, you're sanding against the grain. You'll get up the tree, but using a 2:1, or worse, 3:1 ??? That's pulling a lot of rope to advance yourself slowly. I guess if your feet are hanging in space, doing nothing, that would suffice.

Does anyone just put a backed-up ascender on the rope and footlock up??? You're allowed to swap to a descending device once you get up top. Granted you'll have to clip the ascender on to your saddle and carry it on your hip until you need to ascend again, but honestly, it's not such a big thing. Been doing it for _years_. 

The more complicated you make SRT, the less likely guys are going to be willing to try it. You can be very safe, and swift, and efficient without making SRT a full-blown rigging operation -TM-


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## Tom Dunlap (Dec 30, 2003)

Tm,

Remind me, what do you use for descent?

Sure, clipping an ascender with a lanyard above you would work. Simple. Very. That's if you have a place for your feet to climb. How do you move up the rope when it's free hanging, out in the air? I haven't seen a way to do that. 

I could see a system where you used a long lanyard on the ascener and did an inchworm climb. But after every hitch up the rope you should/would have to take up the candy cane above your descender. 

Unless I'm having one of my thick-headed moments and missing something obvious.

Tom


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## Lumberjack (Dec 30, 2003)

*Re: Simplify*



> _Originally posted by Tree Machine _
> *Guys, I have to say my head spins when I read all your stuff. I've been doing SRT since I came into this profession 10 years ago. I've done SRT all kinds of different ways, different nuances of established technique, different rope diameters, a variety of devices. I have never gone up using a RAD system. A variation of it going down, yes, occasionally.
> 
> Rich mentions body thrusting. I thought that was a technique you use in a pinch, like when the rope you're about to ascend is 5 feet off the ground, you body thrust until you've got rope at your feet.
> ...



I think that you missed the point. The rads is only for yo-yoing, not ascending. I did use it today to ascend, but that was to try it out. Normally, I use a Cmi closed shell ascender, and a pantin. Then I switch over to the 8 with a backup, and work down. The rads wouldn't be neccesary on removals, only trims where you might need to yo-yo some to get the job done. The Rads is plain as dirt. I use the ascender for the top, with a biner and a micropulley. I just got the i'D and I think that it was a good move, but I haven't gotten to work on it yet tho.

On small ascents, it may turn out that I RADS it up, and work down. The way I see using my RADS is on trims. In case you didn't know , you can't footlock through the i'D, so it is either body thrust (that would kill you) or RADS, and the 3:1 is the easyist to set up when using the i'D.

How would you recommend yo-yoing on trims?


Carl


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## Lumberjack (Dec 30, 2003)

Hey Tom, where you talking about RADS for rope ascention from the ground? I don't think that RADS will ever take the place of my ascender and pantin, because of its speed. When I get to the top of where I have to work, I think then I will go over to the i'D, and work comming down. The way I invisioned using Rads, wasn't as a normal setup, but as a option for when I need to go up 20-30 foot while I am working in the tree. From the sounds of it you are talking about always using RADS when you are working. 

If that is what you are saying, then, I think I might have missed somthing.

If you are saying that you are using it like what I am thinking then ignore this post.


Just wondering.


Carl


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## rahtreelimbs (Dec 30, 2003)

*Re: Re: Simplify*

Any major trimwork is going to require up and down movement. I cannot see anyone pruning a White Oak with a big canopy from the top down only. Even if you work the tree in quarters and change your TIP.


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## MasterBlaster (Dec 30, 2003)

Man, I know I said my pipes were down, BUT Geez-Louise!!!

Ya'll are taking the SIMPLE ART of 'A Boy and His Rope' and turning it into a gear-headed, Rocket Scientist sorta thing.

Just gimme my gear(minimal!), and show me the tree.



My motto; Minimal Metal Up the Tree.

Ahhh, I gots lots'a mottos!


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## Lumberjack (Dec 30, 2003)

> _Originally posted by RockyJSquirrel _
> * I'm gonna have to drive to MS and show you how to climb a tree.  *



I would like that, or mabye when I take the ISA Cert test in March I could stop by.

The way I see using my setup of SRT is when ascending, or working from the bottom up, using an ascender, and the pantin. When I am working top down, I will use the i'D after I get to the top. When I need to go up and down, I will set up the RADS, and use it to ascend like DbRT, as the only additional gear needed is a micro pulley (which is optional). I will already have the ascender and the micro pulley does't take up that much room.

That way I get the benifits of both systems, 
easy set up, no isolating
fast ascention using SRT
working down SRT super easy
yoyoing DbRT, while still using the 1st TIP

I think that this might be the compromise that makes both sides (or methods) better.

The more I think about it, the better it sounds.

Removals don't normally need yoyoing, and trims do, but most of the time isolating the limb is a batch ( I would guess)


Does anyone else see the compromise/ merger of the two methods.


Carl


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## Tree Machine (Dec 30, 2003)

> How would you recommend yo-yoing on trims?



Yo-yoing, meaning descending, and then going back up? Well, descend on any descent device that you're comfortable with. Ascend? Slip your ascender on and footlock back up.

I could go into the detail of how that's done, but my effort here is not to belittle anyone's intelligence.

I yo-yoed all afternoon today in a sizable red oak. Limb walk out, drop through a natural crotch, abseil down, do my work, ascend back up. Is that an example of yo-yoing, or is that simply going up and down within a tree's crown?


> clipping an ascender with a lanyard above you would work. Simple. Very. That's if you have a place for your feet to climb. How do you move up the rope when it's free hanging, out in the air?


 If you have a place for your feet to climb? How do I move up the rope when it's free-hanging?? Y'mean like EVERY time I do a vertical rope ascent. I think it's called footlocking.... for the more gear-minded, you may want to use a Pantin, or an even simpler system like what my wife uses in vertical caving, something similar to a mar-bar.

Please tell me if simplicity is bad. Footlocking up a free-hanging rope using a backed-up ascender, as rudimentary as it may be, will get you on-rope and up-rope quickly, easily, simply. Am I out of line here? -TM-


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## rahtreelimbs (Dec 30, 2003)

> _Originally posted by Lumberjack _
> *Removals don't normally need yoyoing.Carl *



With all due respect.

What do you do when a removal has limbs out over a pool or the house? 

Simply saying that most removals don't need, as you call it, yoyoing IMO is a little narrow.

All this switching from one device to another, when my DbRT system doesn't change at all, seems like to much hardware. After stripping down my saddle, the minimal approach is refreshing.

In responce to Brian's comment, to see a really good climber do his work DbRT is really something to watch. Attending a climbing jamboree will prove that!

Don't get me wrong, I am enjoying this discussion. That is why I started this thread!


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## Lumberjack (Dec 30, 2003)

> _Originally posted by Tree Machine _
> *Yo-yoing, meaning descending, and then going back up? Well, descend on any descent device that you're comfortable with. Ascend? Slip your ascender on and footlock back up.
> 
> Please tell me if simplicity is bad. Footlocking up a free-hanging rope using a backed-up ascender, as rudimentary as it may be, will get you on-rope and up-rope quickly, easily, simply. Am I out of line here? -TM- *



What do you use to decend? 

I would think that swaping on and off the ascender would get old, but that is just me. With RADS you can leave it set up if you are gonna do alot of yoyos, or leave it on your side (ascender and micropulley) until you need it.

I do the same as you on ascention (pantin) and normaly work down on a backed up eight (until I got the i'D). I couldn't see swaping over to the ascention system ever time you needed to go up 5 foot.

I think that your simplicity is great, it is what I do.


Carl


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## MasterBlaster (Dec 30, 2003)

> _Originally posted by RockyJSquirrel _
> *ummmm.... Traditional DdRT?
> 
> I'm gonna have to drive to MS and show you how to climb a tree.  *




Lemee know, Brian. I'll bring my lawn chair, and a digcam.


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## Lumberjack (Dec 30, 2003)

> _Originally posted by Rich Hoffman _
> *With all due respect.
> 
> What do you do when a removal has limbs out over a pool or the house?
> ...



I was thinking about a simple removal where the limbs could be butt tied and roped down.

After I get to the top, there will be no swaping of gear, just when I need to go back up clip the ascender and micropulley in the rope above me, slip the tail of the rope through the pulley, and up I do DbRT style.

Really aint very complicated.


Carl


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## Lumberjack (Dec 30, 2003)

> _Originally posted by MasterBlaster _
> *Lemee know, Brian. I'll bring my lawn chair, and a digcam.  *



You had better use mine, so we can see what the picture is about. When are you gonna open the purse strings and get you a PowerShot G2 or 3 like mine?

Carl


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## Tree Machine (Dec 30, 2003)

> I would think that swaping on and off the ascender would get old, but that is just me. I couldn't see swaping over to the ascention system ever time you needed to go up 5 foot.


 It would get old if you did it repetitively. The oak I did today required 6 yo-yo's. If I had to add up the time it took to swap and unswap between ascent and descent, I would estimate it to be around two minutes. That hardly bumps my day.

As far as going up 5 feet, I'd probably do like Butch would do; grab the rope and pull myself up the 5 feet.

As far as a descent device, jeez, use whatever suits you. There are a lot of devices out there. They all do the same thing: allow you to modulate friction on a rope while you're attached to it. That goes for DbRT, DdRT, SRT, WSRT. Check here for some of the many. http://storrick.cnchost.com/VerticalDevicesPage/VerticalHome.shtml -TM-


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## Lumberjack (Dec 30, 2003)

Here is how I ascend, pretty simple.


Carl


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## MasterBlaster (Dec 30, 2003)

I do the same thing, but with NO metal involved.

Purty picture, though!


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## Lumberjack (Dec 30, 2003)

Here is how I work. More metal, but it is great.


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## Lumberjack (Dec 30, 2003)

Here is how I get the benifits of both DbRT and SRT, using the stuff already on the saddle. After the I'd is on it takes probably 10-15 seconds to RADS it.

Carl


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## Stumper (Dec 30, 2003)

I'm finding all of this interesting. Like Butch I'm less than thrilled with all the metal though. It may seem silly but I have a hard time trusting the ascenders and descenders. I like the pantin for an assist and various ascenders can be useful as well but I want my DbRT and hitch to support me. I know in my head that the gear works but Ive learned to trust quality cordage and the knots I've tied myself-there aren't any parts to jam or fall out.


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## Lumberjack (Dec 30, 2003)

As I can tell, it isn't hard to get the benifits of both systems with a minimal fuss, and minimal gear. If you wanted to you could have the whole thing made out of rope, but that wouldn't be cool.

If you notice, the RADS can be as long as the rope will allow. You could keep it close when you wanted to, or let it get long by keeping it at the top of a section of the tree that was being trimmed.

I think that it opens alot of different options with the same setup.

Carl


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## Lumberjack (Dec 30, 2003)

> _Originally posted by Stumper _
> *I'm finding all of this interesting. Like Butch I'm less than thrilled with all the metal though. It may seem silly but I have a hard time trusting the ascenders and descenders. I like the pantin for an assist and various ascenders can be useful as well but I want my DbRT and hitch to support me. I know in my head that the gear works but Ive learned to trust quality cordage and the knots I've tied myself-there aren't any parts to jam or fall out. *



Like I said right after you posted, you could have the whole setup made out of rope and 2 biners.


You could use a split tail to tie into the SRT rope. Ascend and work off of it, and use another split tail with a biner in the end to make the RADS. That would be one way, another is you could put a saftey friction hitch above the i'D or below the ascender, and have a saftey, but that wouldn't make you fell better prob.


Carl


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## Tree Machine (Dec 30, 2003)

I'm finding this interesting, too. Carl, thanks for the clear pics. Everyone appreciates that.

I like the look of the RAD system you've shown. A truth I must point out is that it is a 2:1 mechanical advantage setup. Great if you're hoisting heavy materials up, but in the SRT sense, you have to pull two feet of rope for every foot you go up.

This is not a bad thing, don't get me wrong. You work half as hard, but twice the motion. If I do a deep footlock and grab 24", I go up 24". To me, that's an advantage. -TM-


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## Tom Dunlap (Dec 30, 2003)

Carl's been clearing things up while I've been packing. It seems like all the points are being covered.

The only time I use the RADS is to work the cro, er, canopy. I've posted my ascent system and it is similar to what Carl posted. Once at the TIP the I'd comes out. 

Something that is still confusing me though. If a climber is using a friction device for descending, whether its a Munter, eight or I'd, they can't ascend the tail of the rope. If you footlock the tail, you lock off the device eliminating ascent. Now, if you were using a friction hitch with a slack tender, you could FL back up. You're right back to a SRT or DdRT access climb. That seems to have advantages too. In certain circumstances I could see using this setup. Overall though, I like the way that the I'd works. 

Tom


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## Lumberjack (Dec 30, 2003)

> _Originally posted by Tree Machine _
> *I'm finding this interesting, too. Carl, thanks for the clear pics. Everyone appreciates that.
> 
> I like the look of the RAD system you've shown. A truth I must point out is that it is a 2:1 mechanical advantage setup. Great if you're hoisting heavy materials up, but in the SRT sense, you have to pull two feet of rope for every foot you go up.
> ...




I like that too, but it combines the advantages of SRT and DbRT. As Brian said "I like my 2:1" and this gives it to you, when you want it

I wish that you could buy a device like the I'd that you could ascend, decend, and work off of while being able to FL or Pantin under it, to advance. That would be prime, IMO. be as smooth as an ascender or V.T., be as easy as an 8, and as easy to work off of as the i'D.

Carl


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## Tree Machine (Dec 31, 2003)

*The ultimate device ?????*

So it sounds like what we need is a cross between a Grigri (or I'D), and a Gibb's ascender. Something that allows the rope to pass through direct and straight, and when the curved cam becomes decommissioned (using a handle), a flat pressure (friction) plate would concomitantly engage. No weight on it would be the sweetspot of zero friction, for a footlocked ascent, or limbwalk. Letting go of the handle, cam fully engages and you stop

A Gibb's ascender that allows controlled descent; a truly one-device-does-it-all. The reason this can't be acheived on the Grigri or I'd is that these devices don't allow the rope to pass straight through; the ropes curves within the device, totally screwing it up for a footlock ascent.

Ascenders and rope grabs, on the other hand, DO allow the rope to pass straight through, but the camming under load is complete and non-adjustable. 

I find it hard to believe this ascend / abseil device does not currently exist. Maybe it does. I'd like to see it -TM-


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## Lumberjack (Dec 31, 2003)

*Re: The ultimate device ?????*



> _Originally posted by Tree Machine _
> *So it sounds like what we need is a cross between a Grigri (or I'D), and a Gibb's ascender. Something that allows the rope to p??? through direct and straight, and when the curved cam becomes decommissioned (using a handle), a flat pressure (friction) plate would concomitantly engage. No weight on it would be the sweetspot of zero friction, for a footlocked ascent, or limbwalk. Letting go of the handle, cam fully engages and you stop
> 
> A Gibb's ascender that allows controlled descent; a truly one-device-does-it-all. The reason this can't be acheived on the Grigri or I'd is that these devices don't allow the rope to p??? straight through; the ropes curves within the device, totally screwing it up for a footlock ascent.
> ...



I bet you could make the i'D work. If you removed the anti mess up cam at the bottom, and left the round piece, you could footlock under it. It would have a little slope, as it would have to invert, but it might be worth it. It would keep the cam from engaging, and straighten the path out on the rope. One big draw back is that you would loose the saftey for threading it backwards.

Whatda think Tom?

Anybody else notice the poor angle the cam engages the rope? It only grabs with a few teeth and relies more on the teeth digging into the cover of the rope, instead of clamping the rope as most ascenders do. I might even question if it would work as intended, or if it would just pick out a few strands of the rope, and fail.


Carl

Carl


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## rahtreelimbs (Dec 31, 2003)

Other than less wear on the rope and tree and the obvious ease of rescue..........what are the benefits of SRT? Almosts seems like more money spent to gain very little!


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## Lumberjack (Dec 31, 2003)

> _Originally posted by Rich Hoffman _
> *Other than less wear on the rope and tree and the obvious ease of rescue..........what are the benefits of SRT? Almosts seems like more money spent to gain very little! *



Never having used DbRT, my answers are limited

Ascending the rope is super fast

No need to isolate a limb, (I heard that can be a big problem in some trees) just shoot it over the top, and up you go.

Safter in regards to tail of the rope being drug into the chipper. You can tie it off to the base of the tree.

Setup like mine can yeild benifits of both SRT and DbRT.

Easy to retrieve line. (For those that use a FC, no need to retrieve it)

Easy redirects without the rope rubbing or jaming in tight crotches (gotta hate those)

I can probably think of a few more.


If you think about it, the cost of SRT and DbRT are probably close to the same. SRT has a higher initial cost, but with DbRT you have to replace tress cords, replace ropes from added abrasion. I have been using the same blue streak for 4 months now and it still looks new (or close to it).

I bet the cost are pretty close, here is my SRT gear that I use normally:

CMi closed shell ascender $50 (I think)
Petzel i'D $160
Pantin $55 (optional)

The total is 265. It will take a long while for these items to wear out, and there performance is consistant. Plus you gotta add the saved wear on the ropes. Therefore I think that they are about equal.

Carl


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## Tree Machine (Dec 31, 2003)

*You like the pictures?*

Here's a set of images of how I start out SRT. -TM-


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## Lumberjack (Dec 31, 2003)

That kong has a few miles on it doesn't it.

I perfer a steel biner at the bottom to offset any side loads on biner, or I tie it off.

Benifit: To me (being fresh) SRT is simpler than isolating a limb, or getting the perfect knot and tress cord.

What other benifits can you think of TM?


Carl


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## Tree Machine (Dec 31, 2003)

*More SRT pics*

Here's a couple more. I had a helper today and got some tree shots. I bought some tress cords from Nick last month and I'm experimenting with them here. -TM-


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## MasterBlaster (Dec 31, 2003)

> _Originally posted by Lumberjack _
> *Never having used DbRT, my answers are limited *




There ya go...

Isolating a limb is about as hard as tieing yur shoes, 99% of the time.


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## rahtreelimbs (Dec 31, 2003)

Isolating the right limb has never been a real big problem. Granted, even with the bigshot you may not get that_choice_ limb. But you can get close enough that a few moves will get you where you want to be. SRT surely has it's share of problems isolating the line as does DbRT. Personnally I still don't know how I feel about the non-working side of the rope against the main lead.


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## rahtreelimbs (Dec 31, 2003)

Carl, you ought to give DbRT a good try, just as I should give SRT a try! You may find DbRT not as limiting!


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## Tree Machine (Dec 31, 2003)

*...just my opinion here....*

I always isolate a limb, regardless. That's a lot of the fun of setting a rope, or I guess at that point, it's a lot of the fun of working the shot line and bag.

Yes, the Kong ascender has a LOT of miles on it. Over 5 years of miles and it has never, ever failed. I've only recently begun backing it up with conviction

Yes, it's easier than tress cords because today, for the first time in my life, I actually used one up in the tree. I guess, technically, I wasn't 'using' it, but rather had it there to back up my pieces. I'm not even sure what I tied. I can now see some of the limitations, as well as benefits, first-hand.

Other benefits to SRT?? That would be comparing it to traditional DdRT. I don't use that system, so I'm not a really good person to ask. 

SRT, in and of itself; isolated friction (just your device and the rope, no friction on the tree involved), ability to use conventional descenders, one line in front of your face instead of two. Less 'stuff' to deal with. VERY easy to learn the basic fundamentals. Expanding your climbing horizons beyond the norm. Purity. 

I don't know. I still work off a doubled rope sometimes, even when I'm set up for SRT - add slack to the standing end, clip into the parallel lines and go. Being fluid between the systems, I think gives you more overall technical benefit than just doing 100% SRT. -TM-


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## treehugger01 (Jan 1, 2004)

How about when using DRT in place of a 3 wrap prusik buy that petzl device Tobe has. I rember thinking years about I would like to weld to shunts together to replace the prusik, petzl now has one.
How does it work? Any use the double rope shunt for accending in place of the 3 wrap prusik?
Great thread learning much thank you for your big kohuntas!
heh


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## Lumberjack (Jan 1, 2004)

*Re: ...just my opinion here....*



> _Originally posted by Tree Machine _
> *I don't know. I still work off a doubled rope sometimes, even when I'm set up for SRT - add slack to the standing end, clip into the parallel lines and go. Being fluid between the systems, I think gives you more overall technical benefit than just doing 100% SRT. -TM- *




That is what I have been saying about the RADS.

Carl


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## Lumberjack (Jan 1, 2004)

> _Originally posted by treehugger01 _
> *How about when using DRT in place of a 3 wrap prusik buy that petzl device Tobe has. I rember thinking years about I would like to weld to shunts together to replace the prusik, petzl now has one.
> How does it work? Any use the double rope shunt for accending in place of the 3 wrap prusik?
> Great thread learning much thank you for your big kohuntas!
> heh *



I guess you are talking about the footlocker? It would be as smooth as a regular ascender and easier to advance than a prusik.

Carl


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## Tree Machine (Jan 1, 2004)

*Ascenders and grabs*

Technically the Petzl Footlocker is an ascender, but it might be better classified as a rope grab. Actually, a double rope grab with which you are able to ascend a doubled rope. The Petzl footlocker is slightly less smooth in that it's a bit more involved to on / off than a regular handled ascender. 

The Footlocker is simply a microcender X 2. It's not actually two microcenders affixed to one another, but rather it's own unit that functions identically as if it were two microcenders.

The microcender, I think, has found it's greatest popularity on fliplines and lanyards. The main negative with regards to either of these devices is the removable spring pin, the complaint being that if it were accidentally disengaged, the axel pin could work it's way out and drop you like a hot potato. This can be overridden by replacing the axel pin with a bolt and a nylon insert lock nut. This makes the piece rather permanently installed, and putting it on and off a rope would involve tools and time. Either way, to put these devices on a rope (other than feeding the rope's ends through) requires the axel pin to be physically removed, allowing the cam to seperate from the shell (hence the reason for the little wire cable to keep the cam from falling to the ground.

Removing, inserting, replacing makes these less efficient than a handled ascender, which is like, Bam! and you're on.

Another difference is the contact face of the cams. On the microcender (and footlocker) the cam face has perpendicular ridges, whereas the Kong, CMI and Petzl handled ascenders have a toothed face; many say this could damage your ropes. After many hundreds of personal experiences with these ascenders, I say this is crap information, with the possible exception of a hard shock load. 

Getting back to your idea, treehugger01, about welding two microcenders together, I did that 8 years ago with two CMI ascenders (a left and a right-handed), by pulling the cam pivot pin out, being _real_ careful not to let the cam dislodge and have the spring pop. Insert a same-diameter bolt, twice the length of the pin you just removed. Repeat on the second ascender handle and put on a nylon insert lock nut. Then the bottom of the paired ascender handles needs to have a small hole drilled through them and a rivet installed. The dual handled ascender is now ready to go to work. It is identical now to the current mar-bar ascenders, only without the bar.

Problem with the CMI ascenders is there is a plastic cam-stay whose pivot will break. I've had this happen twice. This is a very dangerous situation as the rope can now easily come out of the shell. The Petzl ascender also has plastic parts, but seems much better designed and more durable, and I've never had one of these break. The Kong is an all-metal design. When I bought them 5 years ago at a TCI Expo, they told me I was one of the first to use dual-handled ascenders in the arborist industry. I pulled the CMI pair out of my backpack and told them I was into my third year with them. There was nothing I could offer them in way of improving their design, as they had totally hit the doggie on the noodle. Their design was impressive and I bought two sets. I still have one set, still unused.

The only improvement they've made since then is that they added glow-in-the-dark handles. IMHO, the Kongs are the safest, most effective dual handle ascender on the market. -TM-


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## Lumberjack (Jan 1, 2004)

TM, or others. I got a question about footlocking. Is it easier to FL up a DRT than a SRT? I can FL up SRT, but I perfer to use the Pantin, and haven't tried to FL up DRT. I was just wondering.


Carl


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## Tree Machine (Jan 1, 2004)

It depends; If you are footlocking DdRT in a conventional sense, the working end of the rope is attached to you. The rope goes up, over your TIP, and the standing end goes to the ground. In footlocking up, your feet are footlocking a single rope, even though there is a doubled rope at your hands and face level (did I get that right? I don't have personal experience with that, only seen it done). Using a Pantin on the single rope is cool if you're not so inclined to footlock it. However, if you use a Pantin, I think it would be next to impossible to footlock without completely disengaging the piece. For the Pantin to work most effectively, the rope below you needs to be tensioned, either by a groundie pulling it, or tying on your chainsaw to keep the rope straight and tight - unless you use stiff static rope, then that's less of an issue.

That would make conventional DdRT almost identical to footlocking SRT, except for the speed with which you go up (SRT being faster).

If you're ascending up a doubled rope, where both ends are on the ground, the Pantin is not an option, and footlocking, I find just a hair easier since there's two ropes to grab with your feet, rather than the one, which requires a little tighter, more concentrated foot grip on the rope.

The photo attached is my wife's vertical caving rig, basically an EZ in / EZ out foot harness attached above to a Petzl ascender; this is for SRT only. The upper ascender here is not shown, just the lower part of the unit. -TM-


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## Lumberjack (Jan 1, 2004)

I was talking about DRT (Double Rope Technique). I know that DbRT is easier because you are only doin half your weight. I kinda figured that DRT would be easier for the reasons you stated.

Thanks
Carl


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## rahtreelimbs (Jan 1, 2004)

Once I set my rope, in the crotch I plan to work from or not, I tie my VT and either body thrust or footlock the tail. The micropulley will auto-advance the hitch on the footlock. On a body thrust I have someone on the ground belay/tend my hitch. In my mind this is one advantage of the way that I do DbRT. I use the same setup for everything. I don't have anything to change out!


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## Lumberjack (Jan 1, 2004)

True, you don't have to change out. I am working (thinking) about how to be able to FL under the i'D. However one big drawback (IMO, no offense) is it is half as fast.


Carl


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## rahtreelimbs (Jan 1, 2004)

Super speed on an entry into a tree is something that I don't concern myself with! On a decent length footlock or body thrust I wind up taking a break on the way up anyhow. I can make up the small time lost by being efficent on my work in the tree. No need to get winded before you even start the work!


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## Tree Machine (Jan 1, 2004)

Lumberjack, Double Rope Technique, designated DbRT, means you are using two ropes. DdRT means _doubled_ rope technique, using one rope, though going up using the two parallel lines.

There is conventional DdRT (doubled rope technique) which looks like image 1, and as described above just before "did I get that right?". 

The other way, also DdRT, is described in the second-to-last sentence of my response above, and shown in the second image below. Don't confuse double rope technique with doubled rope technique. It IS possible to employ both these techniques at once. -TM-


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## Lumberjack (Jan 1, 2004)

I didn't want to confuse the question by saying DbRT, because that would lead me to think about the trad setup were only one end of the rope reaches the ground. That was the reason I said DRT, that way it would be clear that both ends (of 2 different ropes) would be touching the ground.


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## Tree Machine (Jan 1, 2004)

*We need to get the nomenclature straightened out*



> both ends (of 2 different ropes) would be touching the ground.



You mean both ends of the same rope, yes? Both ends of two different ropes = 4 ends.

I'm not bashing you. This is a confusing point, since doubled rope technique can happen in two distinct and different ways. -TM-


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## Lumberjack (Jan 1, 2004)

*Re: We need to get the nomenclature straightened out*



> _Originally posted by Tree Machine _
> *You mean both ends of the same rope, yes? Both ends of two different ropes = 4 ends.
> 
> I'm not bashing you. This is a confusing point, since doubled rope technique can happen in two distinct and different ways. -TM- *




No no no. You answered my ? with your 1st response.

I was refering to 1 rope, doubled over a limb, with both ends touching the ground, or a secure FL. I didn't want to say DbRT because that would lead most people to think about FL the tail (the 2:1 setup).

Anyways, I know the difference of the 2, I just didn't know how to portray what I was saying.

Get it know?

Guess I over thought.


Carl


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## rahtreelimbs (Jan 1, 2004)

Just to clear my end up. What I was referring to on my two last posts was the traditional DRT with the left end clipped to the saddle and the other side operated by the climbing hitch. One end on the ground.


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## rahtreelimbs (Jan 1, 2004)

Carl, what are you referring to when you state: the 2:1 setup?


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## Lumberjack (Jan 1, 2004)

> _Originally posted by Rich Hoffman _
> *Carl, what are you referring to when you state: the 2:1 setup? *



Your setup, DbRT. SRT setup is 1:1.







2:1 on left, 1:1 on right.


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## rahtreelimbs (Jan 1, 2004)

Carl, are you thinking 2:1.......... like a gear ratio of sorts?


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## Lumberjack (Jan 1, 2004)

> _Originally posted by Rich Hoffman _
> *Carl, are you thinking 2:1.......... like a gear ratio of sorts? *



Well kinda... Your setup has a MA (mechanical advantage) of 2:1. For every 2 feet you pull the tail, you go up 1 foot. Twice the movement half the effort.

My setup is 1:1. Every 1 foot I pull the tail, I go up one foot. Half the movement, double the effort (kinda like walking up a ladder).


Carl


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## Lumberjack (Jan 1, 2004)

> _Originally posted by RockyJSquirrel _
> *I think Tom is the one who created the DdRT nomenclature do differentiate our doubled rope setup from rock climber's DRT which is two ropes hanging together- literally Double Rope.
> 
> So,
> ...



I knew it was something like that! 

Carl


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## Tree Machine (Jan 1, 2004)

So, how do we designate clearly which DRT is which, (even though the thread is SRT)? We've only got three here, so it shouldn't be _too_ difficult.

Carls post describing the 2:1 mechanical advantage vs the 1:1 is very clear. -TM-


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## rahtreelimbs (Jan 1, 2004)

> _Originally posted by Lumberjack _
> *Well kinda... Your setup has a MA (mechanical advantage) of 2:1. For every 2 feet you pull the tail, you go up 1 foot.Carl *



I believe you are wrong on this one. When I footlock the tail....say..... 2 ft. I go up 2 ft. The crotch offers no mechanical advantage. To get that another pulley would have to be added.


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## Tree Machine (Jan 1, 2004)

*Nomenclature*



> SRT= Single rope t
> DbRT= Doubled 2 ends on ground
> DdRT= Doubled 1 end on ground



And DRT would be two ropes. I'm OK with that, but I'm not on the committee to decide. -TM-


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## rahtreelimbs (Jan 1, 2004)

> _Originally posted by RockyJSquirrel _
> *Rich, you're mistaken on that one.  *




Someone explain this one?

To get a 2:1 mechanical advantage I believe 2 pulleys have to be employed. The crotch acting as a pulley only offers one.


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## Lumberjack (Jan 1, 2004)

> _Originally posted by Rich Hoffman _
> *I believe you are wrong on this one. When I footlock the tail....say..... 2 ft. I go up 2 ft. The crotch offers no mechanical advantage. To get that another pulley would have to be added. *




Think of the limb as the pulley. Or when you get stuck mud riding. The cable goes from the winch around the pulley and back to the truck. 2:1 advantage. I think that I am right no offense tho.

That is why SRT is great for acsending.

Carl


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## rahtreelimbs (Jan 1, 2004)

No offence taken. That is why we are here to educate one and other.


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## Lumberjack (Jan 1, 2004)

> _Originally posted by Rich Hoffman _
> *Someone explain this one?
> 
> To get a 2:1 mechanical advantage I believe 2 pulleys have to be employed. The crotch acting as a pulley only offers one. *



With 2 pulleys you get 3:1. Follow this as I try to explain what I think. 

1 pulley:

Rope goes from you around the pulley and back down to you, 2:1. Think about this, I am fairly strong (IMO), I cannot body thrust up SRT (easily) because I have to lift my entire weight. DdRT I can because of the 2:1 advantage.

2 pullies:

From the limb, to the pulley on you back to the pulley on the limb, and back 2 you. That makes 3:1

An easy way to count MA is to count the legs of the system. DdRT 2 legs, 2:1, but there is an exception. 

Carl


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## rahtreelimbs (Jan 1, 2004)

I just played around with a small piece of cordage in my basement. I place the cord up over a beam, pulled on one side 1 ft. the other side went up 1 ft. Where is the 2:1 advantage?


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## Lumberjack (Jan 1, 2004)

> _Originally posted by Rich Hoffman _
> *I just played around with a small piece of cordage in my basement. I place the cord up over a beam, pulled on one side 1 ft. the other side went up 1 ft. Where is the 2:1 advantage? *



Here is a quick way to show you. Do a chin up, and then body thrust DdRT. Which is easier?

The advantage is only there if the load is on all the legs, that is the exception. Like Rocky said, if your groundie pulls it is 1:1 because he is only touching one leg of the load. When you DdRT you are touching both legs, making it a 2:1 advantage.

Carl


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## rahtreelimbs (Jan 1, 2004)

> _Originally posted by RockyJSquirrel _
> *Rich-
> Your rope is over a limb 20' up and you are tied in normally, standing on the ground. In order to ascend the 20', you must pass 40' of rope through your hands. That is 2-1 mechanical advantage.
> 
> If Bubba the Groundman tries to pull you up, it is not 2-1. for every foot of rope he pulls, you go up 1 foot. *




Why isn't groundman pulling 40 Ft. of rope? He is doing the same thing that I am, only he is on the ground. The Sherrill catalog had something about this at one time. They stated that 1/2 of your weight is displaced on the limb. You are only pulling half of your weight because 1/2 of your weight is on the limb and the other half you are pulling. When the ground man does it he is pulling all of your weight.


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## rahtreelimbs (Jan 1, 2004)

Try this one. If I pull myself up the 20 ft. I still have 20 ft. left from me to ground that the groundie can't get to. If he pulls me there is still that 20 ft. from me to the ground. Same thing.


Time to move on.


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## Tree Machine (Jan 1, 2004)

*so glad to get this hashed out*

Well-said, Rock. This is precisely why I don't DdRT. You might footlock 2 feet, but one end goes up one foot, the other side comes down one foot. Plus any slop in your tress cord / attachment and you lose a fraction more. If you have any friction pushing a hitch up, that furthers your efforts.

That's why I'm fully into DbRT with ascenders. Or SRT with ascenders, for that matter. They don't slip back even a fraction. If the cord or web attaching you to the ascenders doesn't stretch, there's no loss there. I also like a non-stretch rope, for there is no loss in the elasticity. Ascenders offer next to zero friction, or resistance, on the up-push. You get ~100% of what you put in. This is just a viewpoint IMHO, not a slash on how others do it. I respect technical diversity. -TM-


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## TheTreeSpyder (Jan 1, 2004)

Brian is right, an old puzzle....

You have to measure from you, to the controlling hold, if that is on the ground, you must count that length; if it is the knot next to your head then zero rope is left. Slack after that doesn't count, only the loaded part of the line that you would fall if it was cut is counted as in use at end of lift.

If you start off line over branch 20' high, you need 40' of line. If you pull your self up the 20',there is no line left. 40/20 = 2/1.

If Groundie pulls you up, there is still 20' left from you to where groundie holds line on ground (40 - 20 left over)/20 = 1/1

If ground control lifts you, 1 line is pulled, 1 support moves (1 line to climber)

If you lift your self, you pull 1 line, but 2 lines move that support climber, you must shorten both of them 1' to go 1'. The line dead ending to your saddle and the line your friction hitch lides on both support you.

The trick is, that the we are used to seeing each leg of line serve one purpose, in this unique event, the system is 'closed'; and 1 leg of line seves 2 purposes to lift and support. Notice that witht he 2 legs, either the suppoirt load is 2x or the power is 2x depending on if the system is open or closed.

Any mechanical conversion will always be distance x power still = distance x power but will have a friction cost, there can be no perpetual motion, constantly transfered back and forth, force must trickle out to nothing. So SRT would not pay that cost on ascending, making no power conversion as DdRT. That is good, as these guys polish this to within the human machine powerband. Polishing more and more play out of it it seems....


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## rahtreelimbs (Jan 1, 2004)

Thanks Treespyder.


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## Tree Machine (Jan 2, 2004)

*Clarifying, for the record*

I, too, admit this is a tricky concept. Mebbe some guys are still just a little fuzzy, so for fun, let's turn this problem upside-down, and solve it from the top down, rather than the ground up.

Say you are at the top of the tree. You're standing on a limb that allows your saddle to be at the same exact level as your tie-in point. 

Rope attached to the left side if your saddle, goes through the fork and to your right hand. Pull tightly so your hips are pressed up against the TIP.

OK, start backing down the tree, letting the rope belay through your gloved hand. When your hips are exactly 10 feet away from the TIP, STOP.

How many feet of rope have gone through your hand? Ans: 20 feet; the 10 feet from saddle to the TIP, and the 10 coming back down to your hand. 20 feet of rope to go down 10 feet. Of course, to get back UP that 10 feet, you'll need to pull the same 20 feet of rope .

If the TIP were a pully (ridding the system of frictional losses), and you were to use _only_ your arms to pull youself back up that 10 feet, letting your legs and feet dangle, you would be pulling with a force equivalent to half your weight, since your weight is split 50:50 on each line. _That_ is a 2:1 mechanical advantage. Or you could grab both ropes and pull yourself hand-over-hand (you stud), pulling your full weight with half the number of pulls as previously described. This is 1:1. 

SRT is a 1:1 ascent system, which I consider a main advantage over traditional DbRT since it gets you up there with half the amount of motion. -TM-


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## TheTreeSpyder (Jan 2, 2004)

When you are up 50' and want to make sure enough line is left to descend; you pick the end of your climbing line up and touch it to your chest, the loop of the line should touch the ground.

Because ya need 2x as much line to come down as you have distance to descend.

If you only have 50' of line left to descend 50' with DdRT; it is preferable that ya have a stopper knot as a possitive, mechanical stop at the end of the line, or ya get to ride the 'short bus' home fer kids that don't learn as fast.


i think they even send special ice cream trucks down your street then, ya can tell the ones for the such handicapped learners; it says "Slow Children" on the back!


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## Tree Machine (Jan 2, 2004)

*HSRT?*

Spidey, ya just gotta love your sense of humor. Here's a few SRT pics I dug out from six years ago, when I was really starting to dig on SRT, and was using it more frequently. These were from when I was pre-digital. I had to take digital photos of the prints, so I hope they look OK. -TM-


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## Kneejerk Bombas (Jan 2, 2004)

Worked a tree today SRT.
The first problem I had was the two-to-one load it puts on the crotch. As I loaded and unloaded the rope it had too much slack. The rope would saw back and forth at the crotch from rope stretch and TIP movement. The same problem you have setting up a retrievable lowering point with a second rope.
Once I tied a running Butterfly the slop was gone, and it was still retrievable from the ground. This of course make some of Tom's built in safety features obsolete. 
I climbed of a modified VT which worked really well except on decents more than a few feet. Yo-yoing with a Pantin was simple and working a single line is really nice.
The benefits are apparent, if only the bug of how to attach yourself to the climbing line could be slolved.


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## Lumberjack (Jan 2, 2004)

Maas, can you see the light?


What was wrong with the VT on longer decents? Too much heat?

Just wondering, I never used a proper VT.



Carl


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## Kneejerk Bombas (Jan 2, 2004)

Yes, locks down tight, hard to get to move again, and hot both on your ropes and fingers.
It all takes time to work out. There might be a hitch that works. The VT I tied had a bunch of loops(5 or 6) and three crosses.


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## Lumberjack (Jan 2, 2004)

> _Originally posted by Mike Maas _
> *Yes, locks down tight, hard to get to move again, and hot both on your ropes and fingers.
> It all takes time to work out. There might be a hitch that works. The VT I tied had a bunch of loops(5 or 6) and three crosses. *




I noticed that on the knots I tried. When I backed up the 8, I used a 6 coil prusik. It worked decently, but it would lock up occasionally, and it made huge amounts of heat, that toasted the cheap UT cord.  

Tommorrow I might try with a larger diameter cord and see what happens.

Carl


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## Kneejerk Bombas (Jan 3, 2004)

Backing up the hitch with an eight might work going down, but you would need to remove the eight to ascend, not to mention the set up gets real long.


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## Tree Machine (Jan 3, 2004)

Mebbe use an ascender going up pushing your friction hitch?

Swapping an 8 for the ascender once you're up top could be rather breezy.

Jussa thought. -TM-


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## Koa Man (Jan 3, 2004)

For ascends into a tree, I like to use a 12 ft. straight ladder. That will usually get me to the first branch of most trees. Once in the canopy, it is easy to climb up (most of the time). At a trade show I watched one of the vendors demostrating all these fancy devices and a guy from Texas told him, "I can have my groundman set my 28 ft. extension ladder against the tree and I'll be up and cutting before you even finish setting up." He was right.


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## MasterBlaster (Jan 3, 2004)

Watch out there, Koa.

This is a gearhead thread... NO ladders allowed! 

:angel:


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## Koa Man (Jan 3, 2004)

Sorry MB,
My bad. I'll go back into my hole now.


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## TheTreeSpyder (Jan 12, 2004)

i found these 3 versions of SRT for cavers:

Cave Prusiking 

Frog Technique 

RopeWalker 


Only the prusik system, does not address the inefficiency of using energy to keep chest right over the lift of the legs. i think the chest is most leveraged weight to fall out of the line of movement. This is pointed out in "On Rope" etc.

i've tried to use that property to power hip thrusting with some success. Throwing back the leveraged force i fought to with to climb SRT a whiles back, trying to turn the chest weight into a positive

i was wondering if you SRT-ites have had problems, comments, solutions etc. about handling chest weight falling away from line. As usual i think the safest and most efficient way to move something is balanced.


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## Lumberjack (Jan 12, 2004)

I don't have a problem with falling away. I use the pantin and a CMi closed shell ascender. The TIP on my saddle is pretty close to my COB. Also I wrap my hand around the acender and keep constant pressure pushing in on the pin, no reason, just conveniant.


Carl


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## Burnham (Jan 13, 2004)

I SRT with a modified Texas system, this is similar to the prusik system, I believe; two handled ascenders, one with a pair of footloops and both lanyarded to my saddle's center clip point. I do have to counter the tendency to fall away from the ascent line. I keep one hand on each ascender as I climb, and by swinging my heels under my thighs, in line with the rope, before pushing upward and using some arm strength to keep my chest close to the rope I prevent the tendency to fall away. By keeping close as I climb, rather than letting myself fall away from the rope on each stroke and having to pull back in repeatedly, I don't seem to expend too much energy in the effort. I use a Ness saddle, which gives me the option of clipping in at two seperate points on center. The higher point places my body in a more upright position, thus I choose that to mount my ascender lanyards to. Changing over to rappel device, I clip to the lower point, which gives a more sitting position to very comfortably rap in.

While this is not as energy efficient as a ropewalker system, it is simple, compact, straightforward to use, and is easy to mount and fit. I have seldom needed to SRT over 100 feet, never over 150 at one whack, so for me the level of efficiency is satisfactory, and the benefits of this system outweigh that drawback. If you want to see a graphic of the system I use, check page 23 of the 2003 Sherrill catalog, bottom right. They duplicated my system pretty closely. Maybe one of you whiz-bangs can post a copy of it here, if anyone is interested.


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## Tom Dunlap (Jan 13, 2004)

Getting caught up on this thread has been interesting. Lots of good discussions and some head scratching too  As I read through I typed up some running commentary.

There seems to be a real prejudice against change. This is human nature I quess. I bet we could transport back to the time 
when Davey and Bartlett started to require their climbers to tie in instead of freeclimbing and hear all of the same lines. This was 
back in the teens and twenties. Climbing is moving forward.

Why don't people trust mechanical climbing devices? Because they're metal? That's silly. The airplane I rode in last night is sure 
complicated but it is the best thing going for long distance travel. How long would it take to walk from Dallas to Minneapolis? 

Isolating limbs isn't always easy. Even if climbers used SRT to access the canopy and then changed over to DdRT they would 
save a lot of time. I've climbed for close to thirty years and have spent the last five or so working the bugs out of SRT. I think 
that I have an open, critical mind and look at all the pluses and minuses of change. The climbers that I've talked to that have 
open minds have all understood the value of incorporating SRT into part of their climbing skills. 

I made up a set of double headed Kong ascenders about five years before they made them from the factory. On mine, I had 
only one handle, not the butterfly handles that Kong has made. The older, modular, Kong ascenders leant themselves to using 
through bolts. 

The nomenclature of SRT/DRT/DdRT came out of a discussion on the ISA forum several years ago. DdRT is when a single rope [or two tied together,effectively becoming one] are draped or doubled-over a limb and paired together for ascent. DRT uses two seperate ropes and anchor points. Arbos would call this double crotching. 

Footlocking a doubled rope is sometimes easier for people. There is more rope to add friction to your grab. Once the climber 
has their technique worked out they'll be able to FL a single just as easy. 

There was a comment about the RADS being 2:1 and this wasn't efficient. Well, take a little time and look at a DdRT setup. 
that is 2:1 ALL of the time. While you're stripping rope in and out, I'm moving around at twice the speed and effort. Certainly a 
time/speed improvement there.

Over the weekend I played around a little with a friction hitch and slack tender for SRT. I think this is going to be a quest to find a cord/rope combination that works smoothly just like the quest for a split tail cord. There has got to be a combo that will grab and slide smoothly and not heat up so much. 

Mike found one of the limitations of SRT. Since there is more rope in the system and a higher load at the TIP, there will be some rope movement. I've considered using a FC in thin barked trees if I thought that I might damage the bark. So far, I haven'r come across a tree where I've felt that I needed to do that. Hackberries in the spring will require a FC though. 

Tom


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## RescueMan (Jan 13, 2004)

*Hitches for SRT*

There are a number of hitches that have historically been used for ascending a single line (most of which have given way to mechanical ascenders). The hitches include the Bachman (which has been pictured), the Klemheist, the Kruzklem, the Prusik, and the French Prusik or Autobloc. A variation of the prusik which advances more easily is the 3-over-2 wrap, but it needs to be tied around your fingers and then slipped over the end of the climbing line.

Traditionally, SRT was done with prusiks because they grab the rope so reliably. But they can be buggers to slide after they've been loaded. And to work well, they have to be tied with cord of about 75% the cross-section of the host line.

The masters of SRT are vertical cavers who have to descend sometimes several hundred feet into a cave and then climb back out, often with a number of "re-belays" (intermediate anchors) and offsets. They have to perform very efficient technique and be able to pass knots and switch ropes in midstream, both in ascent and in rappel.

There are no ascending hitches for descending in SRT (the munter hitch is commonly used for rappel, but not for ascent). Some kind of rappel device is necessary, and it is necessary to know how to convert from ascent to rappel or visa versa while hanging on rope.

The best single source for information on SRT is the book On Rope published by the National Speleological Society.

- Robert


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## MasterBlaster (Jan 13, 2004)

As opposed to treework, SRT appears to be the perfect technique for spelunkers.

Everyday treeworking?

Hmmmm...


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## NickfromWI (Jan 13, 2004)

*Re: Hitches for SRT*



> _Originally posted by RescueMan _
> *B]...There are no ascending hitches for descending in SRT (the munter hitch is commonly used for rappel, but not for ascent). Some kind of rappel device is necessary, and it is necessary to know how to convert from ascent to rappel or visa versa while hanging on rope....*


*


Not true. It would be better to say that there are no commonly known ascending hitches for descending. 

One thing that would help SRT really take off would be if people could try it out without having to drastically change how they do things now, no new gear, etc. If a person takes some time to find that ascending hitch that will allow them to descend safely on a single line, they can work through a tree with the same motions they are already used to (ie, pulling the tail of their rope while the slack tender advances the hitch).

One thing I know that helps for this is to use a fatter rope. I use a 5/16ths for DRT and close to half-inch for SRT (which I admit right now that I do not use exclusively...it's an "every now and then" thing right now. I'm still working out the kinks!). It also helps if you can acquire a "high tech" line with a high heat resistance. Vectran, technora, and nomex come to mind.

good luck!

love
nick*


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## Tom Dunlap (Jan 13, 2004)

Robert,

I'm glad to see you taking part in this discussion. I've followed some of your responses on BCSAR for a while.

You're right, On Rope is a good source. Anyone interested in working rope needs to read that cover to cover. There is also a lot to be learned from discussion forums. This is where some of the details are worked out and shared.

Nick is right, there is a solution out there but it hasn't been found yet. In my head I can visualize what's needed but now I have to search for the right combination of tools to accomplish a two way system. 

SRT does work in trees on an every day basis even though there are some people who can't see the advantages and uses.

Tom


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## MasterBlaster (Jan 13, 2004)

> _Originally posted by Tom Dunlap _
> *
> 
> SRT does work in trees on an every day basis even though there are some people who can't see the advantages and uses.
> ...












Its all good.


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## Tom Dunlap (Jan 14, 2004)

Butch,

You just happen to be the most vocal one in the room. I've talked with others who can't open up to other options. I've been advocating SRT for many years at competitions, trainings and conferences so I've heard most of the reasons for not using SRT. None of which really holds water 

Tom


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## Kneejerk Bombas (Jan 14, 2004)

*Re: Re: Hitches for SRT*



> _Originally posted by NickfromWI _
> *It also helps if you can acquire a "high tech" line with a high heat resistance. Vectran, technora, and nomex come to mind.
> 
> good luck!
> ...



It's my experience that the heat resistant lines do not hold up to abrasion as well as some other fibers. There is added heat descending SRT, of course, but there is also a lot more friction.

How about using a combination of a mechanical device with a straight through rope feed and rope hitch? Like a positioner and a vt.


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## Bradley Ford (Jan 14, 2004)

In "The Tree Climber's Companion" 2nd edition, Jeff Jepson makes the following admonitions:

(Page 49, in bold italics, in context of a static climbing system "Do not descend solely on the friction hitch; instead use a figure-8 descender."

(Page 86 "Never use the Prusik knot, or any other friction hitch, as the sole means for descending when using a static climbing line system. The only exception is when using a dynamic climbing system."

Why does Jepson say you can't safely descend using only a friction hitch with a static climbing system?


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## RescueMan (Jan 14, 2004)

*Hitch for descent?!*

While I don't have the experience you guys have in DdRT climbing and descent with Tautlines or Blakes, I would have to agree with Jeff Jepson (The Tree Climber's Companion) that it's not possible to safely descend on a static line solely on a friction hitch.

With a doubled rope slung over a crotch or a even friction-saver, most of the climber's weight it dissipated in the friction of the rope moving over it's upper support point which leaves far less than half the climber's weight to be controlled by the friction hitch, making it possible to do a controlled descent (this is also why an autobloc hitch on the brake side - below - a figure-8 rappel device is so easy to control). In addition, because there is two feet of rope moving through your friction hitch for every foot of descent, this gives a 2:1 friction advantage.

On a single static line, all the climber's weight would be on the friction hitch making the hitch grab sometimes too well and be difficult to release. When it does release it tends to result in sudden uncontrolled acceleration and any attempt to stop the descent can result in the melting of the hitch cord and either fusing to the mainline or severing.

Heat-resistant cords typically are too slick or too stiff to work well in friction hitches (the size ratio and the stiffness ratio of the hitch cord to the host cord is crucial to proper function).

Even using a prusik hitch as a back-up above a descent device has resulted in a number of deaths and near misses among very experienced climbers and cavers (Oh, BTW MasterBlaster - don't ever call us cavers "spelunkers" - that's the term for amatuers!).

I had thought of offering a $20 prize for anyone who could come up with a hitch that would SAFELY work for descent on a static line, but I don't want to be responsible for getting any of you killed.

Climb safe and land on your feet, 
- Robert


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## Lumberjack (Jan 14, 2004)

One reason is because in other fields like caving, there have been many cases where they paniced and squeezed the knot harder (instinct), making them dirty up the cave with their inards.

Another is the extreme friction from the knot supporting all the climber weight.

Probably some more.


Carl


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## Tom Dunlap (Jan 14, 2004)

This afternoon I spent some time at my favorite mountaineering store. I wanted to tap into their knowledge and look at some other friction tools that I'm not familiar with. In short order, three of the sales people were involved in the discussion. I showed them how a Distal with a slack tender worked. They were impressed. This shows that there is room for arbos to teach othre rope people a thing or two.

Making blanket statements is a challenge to creativity. Think back to how arbos have pushed their skills in the past few years. There are many arbo-specific tools used now. Also, many knots have been tweaked to meet our needs. 

With some thinking and sharing I believe that we can find a solution to this quest. I might just come back and hit you up for the twenty 

Tom


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## TheTreeSpyder (Jan 21, 2004)

Tom on that site you posted at TreeB*zz (site i use as this expansion, sometimes differint explanations, secret supply to post here etc. ) as i was scurrying around; i found this real neat breakdown from Bruce Smith's *On Rope Catalog * that shows for free these detailed systems seperated like in his and Padgett's monumental "On Rope" vertical roping's "bible" to so many rescuers, mountain, ice climbing, riggers, military etc.! A fairly cheap must have for really understanding the challenges of friction and camming systems and more, Sherrill #16201 IMLHO!

i think it will puts forward a lot of terms of systems, and the assumed elements of those systems to be able to talk and be on same page etc.(not as bad a jargon as SWL your SRT but TITS ain't a PITA, just like in DdRT, See ANSI-like we talk!). This SRT stuff is a lot more invisionable, with systems drawn out, and them talking about choosing and maximizing a system to a specific body type even!!

The Same Site (On Rope) , has a list of Free 20 DownLoadable Guides to Working with Ropes inways that may be new and stretch a lot of understandings. If ya couldn't a budget the book this round like me. (If it wasn't already here doggy eared), maybe ya can afford these; the price is certainly right!

This page from there claims "A Double Bungee RopeWalker is the Fastest and Most Efficient Rope Climbing System in the World" and displays it in detail, with all componenets named, shown etc. Along with their 2nd pick apparently the Mitchell system. i think either would deal with inertia better than a stop/start 'frogging' and with right style make a smooth motion that carries through to the next, rather than needing to be started again. Or as i say, so you don't have to re-inertia-lize the system, in my whimsical, satirical mental pix. i believe this componenet (inertia) can help increase system of ascending efficiency greatly, if ya got the smooth continuous lift style right.


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## TimberMcPherson (Jan 26, 2004)

Okay tree machine emailed me this. He is currently cruising New Zealand and isnt able to play with you guys!

"Could you do me a major favor? Could you drop a line into the 'Meat of 
the SRT' thread and tell the guys that I'm feeling a great deal of pain 
NOT being able to contribute to that session? The other threads I can 
survive without, but not being part of the SRT thread is just killing 
me. I would really appreciate you doing that."




My Job here is done

Timber


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## Lumberjack (Feb 19, 2004)

Just bumpin this thread back up. It seems we are starting the discussion up again.


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## John Paul Sanborn (Feb 20, 2004)

> It also helps if you can acquire a "high tech" line with a high heat resistance. Vectran, technora, and nomex come to mind.



Look at the wear charecturistics of the product.

I've been told by a treeman218 has told me that that some technora will loose it's strength rather quickly, and should not be used for human suspention.


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## RescueMan (Feb 20, 2004)

*High Strength Cordage*

I posted this link on another thread. Check out this report on the characteristics of the high-tech cordage:

Comparative Testing of High Strength Cord

- Robert


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## RescueMan (Feb 26, 2004)

Earlier in this thread there was a lot of head-scratching about why DdRT is a 2:1 system unless the groundman hauls the climber up.

This example might help:

You're driving a 2-horse wagon and you get stuck in the mud. Fortunately you have some rope and a pulley and there's a tree just ahead of you. So you attach the pulley to the tree, tie one end of the rope to the wagon, run it through the pulley, stand next to the wagon and pull while the horses are straining at their traces. The wagon still doesn't move. You're pulling 1:1, through a stationary pulley (TIP or change of direction).

Then you get a bright idea. You climb up on the driver's seat of the wagon and yell giddup to the horses while you brace your feet against the footboard and pull on the free end of the rope. Now the wagon pulls free. Without changing the system, you've turned it into a 2:1 because for every pound of pull on the free end, your feet have to press into the footboard with one pound as well. If your hands are pulling with say 100 lbs and your feet are pushing the wagon with 100 lbs, then you've created a 200 lb force to assist those tired horses.

The wagonmaster can be a tree climber, and the pulley can be a crotch. For every lb you pull down on the climbing rope (DdRT), you lighten yourself (lift your weight) by one pound. This gives you two lbs of lift for every pound of pull. If the groundman is doing the pulling, it's like standing beside the wagon - 1:1!

Is that any muddier? Or are your horses still stuck?

- Robert


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## MasterBlaster (Feb 26, 2004)

Good explaination, Rescueman!


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## Tom Dunlap (Feb 26, 2004)

Finally a better way to look at DdRT MA!

Thanks a lot!

Tom


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## TheTreeSpyder (Feb 27, 2004)

Ummmmmmmm; then if there was just a single line; and you pulled 100# with arms (first example?), then there would be 0 force on feet and you would have a 1:1, just pull 100#?:alien: 


i would think that you needed that attatchment to the wagon to move the wagon, else you would just pull out of it, so that part of the loading does not give the 2:1?

i think the magic trick is that the pull line in the first example; is just a pull redirected off of the pulley; pulley/hitching/tree takes on 2x force of pull; you pulling on one leg; and the wagon pulling on other. The system is 'open' to allow the extra force into the equation.

Sit in the wagon and pull(close the open leg); the system has now become self contained; it is not 'open' to other forces, there is just redirect and load, the pulley now takes on just 1x load; because the system is closed-other forces are not taken on. Now the 2x function is on the load; as the pull point also a load hitch point, serving 2 seperate functions at once. Grabbing both lines at once and pulling would give speedier 1:1; grabbing just the one not tied to wagon, gives 2:1; but you have to pull at 2x speed of wagon to maintain helpful force. So your pull position, also is a load attatchment point, then the tied end is another, fer 2x; i think the confusion is not seeing the duality of that service point of pull in this system; not giving it that 'count' on the pulls on the load. 

Now the hardest part would be to get it started; if it won't budge, i might try to tie down the pull end tight as possible to the wagon, and bend it to the side sharply, then start pulling quickly as possible if that high leverage force fed into the 2:1 werked. Failing that i might (with an extra leg of line or extension on pull end), untie the free end from the wagon and try to take as low a friction redirect off the wagon back to the tree for 3/1 - friction; slight sweating/leveraging of line to start still appllicable IMLHO. Hey; a lil'guy needs extra help!

At least that is the way i've scrunged around in this self taught hodge podge dance and have come to see it.


Orrrrrrrrrrrrr sometin'like dat!
:alien:


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## RescueMan (Feb 27, 2004)

> because the system is closed


You're on the wrong track here. Both systems are "closed". For every action there is an equal and opposite reaction.

In the 1:1 standing on the ground beside the wagon, of course your feet have to resist your pull with the same force, but they're trying to turn the Earth. This IS a closed system and your force will change the rotation of the Earth, but not so you'd notice.

In the 2:1 on the wagon, the system is likewise closed but the force applied in reaction by your feet WILL move the wagon. The only difference between the two examples is that the wagon is a lot less massive than the Earth. For all practical purposes, you can discount the effect on the Earth.

When you pull on your DdRT climbing rope while hip thrusting, you're imparting an equal force in both directions, up on one side of the rope and down on the other. If you're at all lighter than the Earth, you'll notice a 2:1 advantage.

- Robert


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## TheTreeSpyder (Feb 27, 2004)

i'm sorry; i don't see it sir......... (edit-swooped on posting by Dan speed typing, speaking to RescueRob)

There is an opposite and equal reaction to everything; that is why i argue with MM so much; tell JP the short side of things......

i look at the leg use in your examples to provide extra muscle and extension per pull; but no power conversion without forsaking the pull distance for more power. i think the Equal and Opposite reaction is of course true; but will be in all examples

i believe there are 2 line pulls on the load, powered by one line pull to make the 2/1.

If you had the 2/1 setup; and you grabbed both lines at once to pull (like footslocking up a doubled line like it was a single one); you would have 2 lines pulling, but be powering 2 lines at once, so you would have 2/2 :: 1/1? 

Or no pulley, just a line tied to tree, to draw yourself in(sitting in wagon); would be pulling 1 line, that pulled once on wagon for 1/1; irregardless of foot position IMLHO. i don't think that pushing with feet as you pulled a 1/1 would give MA of 2/1; so i don't think that is the deciding factor. If you weren't pushing with legs on wagon, or connected some other way (weight, seat belt etc.); you would just pull yourself out of wagon; 2/1 , 1/1 ?

i beleive it is simply, that you are pulling 2x as much line as motion achieved; it does this by you having to shorten each leg of line 1' to advance wagon 1'. If you were cranking a hand winch, bolted to the wagon it would have inalterable placement; yet the MA beyond what the winch gave would be from the line lacing i think. Cuz you would have to give up distance to get power all ways and always; dems da rulez! ...As i'm sure you know .

By closed system i mean that all lines terminate at support and load, no matter how many legs of line 1,2 or 15; the support will only incur 1xload; until you 'open' the system to more pulls/pushes IMLHO.

i think hip thrusting reduces load and alos friction on support, doesn't give MA.

i do enjoy your universal view of drawing the Earth etc. into the equation; but do not find such existential philosophies/physics to be a determinate factor here; but rather constantly present; thereby not lending definition.


Now, jest to start more trouble; i'm picturing big stagecoach wheels on small axles, so perhaps getting out and turning a wheel by hand(depending on design might just turn one side at a time) for some help would be best; by taking leverage over the rolling resistance of the axle/wheel; especially one without bearings; or other frictional disadvantages IMLHO; especially noticeable riding up any incline or stone in the way; also lightening the wagon.


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## RescueMan (Feb 27, 2004)

> TreeCo said: The only problem I see is that the climbing system only looks like a 2/1 ma system when in fact it is not.



I understand the confusion around this, but DbRT is a theoretical 2:1 MA system, just as the wagon system was.

And you bring up a lot of valid points that complicate the actual climbing system, mainly the effects of friction, which in this case are actually an asset.

But try hip thrusting on a single static line with your feet and hands in the air. You can't do it. What allows you to lift your weight at the hips is that you are pulling down with an equal force (equal and opposite) with your arms. But the pulling down with the arms doesn't at first advance the rope (it's like you're pulling against a fixed line) until the hip thrust sufficiently unloads that side of the rope and reduces the friction enough for your hand pull to advance the rope downward. When you weight comes back down on the TIP, the friction allows your hand to easily hold the advance until the hitch is moved up.

The less friction at the TIP, the more the load is equally shared by the arm pull and the hip thrust. If you had the rope through a ball-bearing pulley at the TIP, it would become obvious that the arms and the hip are each doing half the work. And if you're strong enough to pull half your weight, you could raise yourself on a frictionless TIP with your arms only. Which makes it a theoretical 2:1 MA system.

- Robert


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## TheTreeSpyder (Feb 27, 2004)

Hmmmmmmmm In My LIL'LowlyOpinion;

Not to be more argumentative than usual...........

When i read MA; i generally think of increasing power/losing speed or the reciprocate of losing power but gaining speed; in excess to the effort expended speed x power.

i see leg pushes, hip thrusts, hand pulls etc. as effort expended; perhaps more effiiciently sometimes but effort expended to get more lift/pull/push etc. That extra comes from calories consumed, less losses to efficiency of use, 'machine processing' etc. to give you the energy to perform. This energy came from the sun etc.

A DdRT would be a 2/1 theoretical MA, less friction. The {2/1 - friction} will equal the expended work force (effort x distance applied); disallowing rope stretch, flexing of support etc. Cuz, play don't work! And if ya look at the leveraging at just 1 degree off of straight, jsut the smallest imperfection in a perfect balanced/straight machine gives the greatest dynamic loss per degree of flex etc. Bt that also means that those subtle nuances polished out as close to perfection as possible makes one race car etc. faster than another, one system silkily, smoothly balanced, to a ballet of gracefull power.

i think these things are all prevailing, and that olde Greek Phycisits were also the Philosophers and tried to show these dynamics as so prevailing and ruling on this Earth; that they defined them as consistent in both fields at once.


Orrrrrrrrrrrr something like that!
:alien:


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## Kneejerk Bombas (Feb 28, 2004)

> _Originally posted by TreeCo _
> *Try this......tie a rope to a 50lb weight......put the rope over a limb and try to raise the weight into the air. The friction of the crotch will make you have to pull way more than 50lbs.
> 
> Dan *


It's easy if you think of it like this:

If you stand on the ground and pull 50 pounds, you pull one foot of rope to advance the weight one foot. That's one to one.

If you *are* the weight and pull the rope one foot, you only advance a half a foot. That's two to one.

Like Rescue guy wrote, the friction can act as an advantage like in body thrusting, or a disadvantage, like in pulling 50 pounds up from the ground with the rope over a limb.

If I read Spyder correctly, about the same calories are burned thrusting, wether you thrust or not. It seems easier to thrust because you are using different (and bigger) muscles.


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## TheTreeSpyder (Feb 28, 2004)

Nahhh Mike, i think more calories would be used, but perhaps greater efficiency etc., single strategy to serve several purposes etc. by body thrusting; that is the defining element to me.

Friction costs your efforts on lift, but eases efforts on hold/lower in trade; it can also isolate/buffer how much line needs prestretched, help to hold a sweated in force, but limit amount of dynamic shock absorbing or energy storing line in exchange. A trade off/ rearrangement to everything. Strong or flexible temper in metals, deadwood (not decayed) can be stronger, less flexible for homes etc.; a Live Oak seems to me to grow slower but tougher in trade than other of our oaks, with a local water oak on the reverse end of the scale. i use the 'reptilic scaliness' of the bark as a thumb rule for defining strong/slow, weak/fast in local trees.

Law of Conservation of Energy (m'Lady properly termed this for me years ago): The calories thing was a comment about energy/effort put into something for more power x travel vs. redistributed power x travel from 'deflecting' given efforts off a machine to gain more power or travel (but not both at same time) from the output of machine. If you expend more energy, that is not MA; it might be more strategic but not MA as i understand it. MA gives more power or speed (but not both) without extra energy and takes some kind of simple machine to create. The machine takes the finite/set amount of workforce units (power x travel) you create by effort , and rearranges them to more power x less travel or less power x more travel; but less frictional losses (as a cost of conversion) the power x travel output by the machine equals the original workforce units you expended. The work energy is always converted, never lost or destroyed; even from calories to person to line to work, it is all accountable, a set/finite amount.

Energy is never lost or magically appears, it is a finite amount just converted to your use, as it rolls on through to something else.
Gasoline is favorite pruf i devised, by the high energy that has been stored for millions of years and never lost, originally coming from vegetable calories (units of heat energy); that came from the energy of the sun etc. It all has ineficiences; but is a traceable set amount, if you knew how to see it, even the inefficiencies of different , individual frictions and digestions have a set amount in the formulae that all adds up to what was initially expended etc.. 

Every machine is a transmission. You get power or speed out of a set amount of workforce units made by the motor source. Downshifting or stepping on gas gives more power, one uses MA, the latter more energy. In this way you get power (for takeoff) or speed from the same source, but not both; without adding energy. That is why better, more efficient tools are so good, the energy is a finite thing, and better tools squeeze more out of that. The dynamic changes per degree increase so much as you get close to perfection, that they become a silky feel and smoothness that catches your eye etc., as in all things.

i think the leg on the wagon example used more energy and served as necessary mount on wagon for pulling force, but is not MA by these exam-eye-nations. 

i also think that you could body thrust or 'kip' up, and catch on hands without arm pull if you chose and fit enough; prolly wouldn't be very smart! i get that from gymnastics, enough explosive force with heavier legs and lower torso alone can overtake inertia of the rest of yourself to give lift; but it would be more efficient to pull with arms too, and take advantage of the force as it died down, but still enough upward force that arm lift would not be against whole body weight. In DdRT, the 2/1 arm pull wouldn't have to fight as much friction, as it wasn't facing as much wieght..

DdRT is 2/1; 2xpower at half speed - friction; friction of branch, bushing pulley, bearing pulley etc. grow more efficient as less friction is involved, or gaining leverage over present friction with larger sheave. Speed being considered faster if you have to pull 2 feet as much line in the same amount of times that load moves 1 foot. But never quite reaching 2/1, there must be efficiency loss, there must be friction as a cost of the machine use/conversion, for there can be no perpetual motion machine, that could run forever off the same energy source due to it's efficiency and force funneled back into itself to keep going. Just as a pendulumn will slowly come to standstill.


Orrrrrrrrrrrrrrrrr something like that.........
:alien:


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## NickfromWI (Feb 28, 2004)

Dan, I think you're on to something here. People often tout the 2:1 MA as a reason why DDRT is better than SRT. It's not so much that there is a mechanical advantage...it's that you're unweighting the rope before you pull up the slack. 

But still, you can't do this with SRT.

love
nick


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## Lumberjack (Feb 28, 2004)

I am growing fond of DdRT. I am not sure if it is just because it is new to me of what, but I like it. I am using UT, because I still have an eye to eye cord from when I first started, and a VT with a micro pulley. I havent used it too much yet, but I might do something like TJ setup. The RADS is cool, but I like new things. Someone said they wondered what would happen if someone learned SRT and then DdRT. I am just tryin it out, but I like the friction hitchs. 

Another thing on SRT. When climbing with RADS (through a e-mail with Rescue Man) is to put an etire on the upper ascender. That might be the ticket to make climbing with the RADS (not towing it up) feasible.


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## RescueMan (Feb 28, 2004)

*RADS*

What Lumberjack's refering to is the RADS system presented by Michel Goulet of Ottawa, Ontario to the International Technical Rescue Symposium in 2000 (see attachment).

This one is made from a Grigri, a handled ascender, a pulley, and an etrier (or foot ladder - a simple foot loop will do as well). It's acutally a theoretical 3:1 MA system (3 legs to the climber), sort of a movable TIP for doing DbRT climbing on a SRT system.

Does anyone know the history of the RADS? Did this guy invent it?

- Robert


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## Tom Dunlap (Feb 28, 2004)

inventing and popularizing are different. Kind of like the history of the Blake's hitch. 

The 2000 presentation is the earliest that I've seen anything like the RADS. I can't believe that someone else didn't come up with something similar though. 

Tom


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## NickfromWI (Feb 29, 2004)

Here's how I climbed a tree today...


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## RescueMan (Feb 29, 2004)

Nick,

Do I understand correctly that you're climbing SRT on a rope hanging on a side-loaded carabiner? Why not use a running bowline to choker the crotch? And why not leave the throwline on the eye in order to pull the rope back down when you're done?

- Robert


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## NickfromWI (Feb 29, 2004)

Yep, climbing on a side loaded 'biner. I weigh 155, so I think I'm in the clear. 

I removed the throwline because I just used the single line for entering the tree. When I got to the TIP, I unclipped the line, ran it through a friction saver, then clipped it to me, along with my friciton hitch. It worked quite nicely!

love
nick


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## Kneejerk Bombas (Feb 29, 2004)

This drives me nuts.
Sideloading a carabiner is as wrong as wrong can be. You are never going to a pro in my eyes, when you practice what you know is wrong. Knowing you do things like this makes me worry about the splices or rope work you do, I won't hire you.
Our industry is so loaded down with mediocracy, and often times worse. Look at the cover of Bailys woodsman supply cataloge. There is a picture of a well known author and arborist/logger. What's he doing? A rec climb up a beautiful, mature, thin barked tree, with spikes on!
If you don't care about trees, how can you care for them? If you don't advocate safe working, how can you sell safety gear?


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## NickfromWI (Feb 29, 2004)

Mike, how is it wrong. 

If I can climb the tree like that, and a hundred other people can use the same system without fail, why is it wrong?

When "industry publications" offer suggestions* using the same technique, why is it wrong?

ANSI does not frown upon this practice. (By the way, my splices are done in accordance with ANSI).

Mike the only evidence I've seen of side-loading being dangerous is when dealing with HIGH loads, when loading across the gate, and people simply saying it shouldn't be done.

I am all ears....prove it.

love
nick




*See page 76 of '03 Sherrill catalog....sherrill IS an industry publication


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## Tom Dunlap (Feb 29, 2004)

Mike,

Jerry B. offered an explanation of the Bailey cover on Treeb*zz a while ago. You could search on his name and pull up the thread. If I remember right, the pic was taken in about '86, a long time before throwlines and SRT had made a presence in arbo work.

I agree with you about side loading but not quite as vehemently. 

The bounce from ascending can add a larger load on the TIP. At a minimum, double, and probably more. There really isn't a good reason to use a biner in a sideload situation when a running bowline or screw link would be better.

Tom


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## murphy4trees (Feb 29, 2004)

Nick,
I AM with Mike on this one..... that's two in a row...
The rules are the rules for a reason... That reason is waiting for me to come home for dinner at the end of the day...

"figuring" you can "get away with" breaking the rules for whatever reason contradicts the whole new school philosophy. And in this situation there is no reasonable need.... you can easily replace the biner with a secure knot. Just put the other end of the climbing line through the ring of the throw ball, tie an overhand knot in the end of the climbing line and pull that end up first....

I readily admit I have broken the "rules" in the past by overloading lines past the SWL of 10%.... but only when there is a good reason ( and not life support lines)... I make the call when I judge the benefits far outweigh the risks... Here there is no need...


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## NickfromWI (Feb 29, 2004)

Where is this a rule. So far, it seems it is just something that some people think is the way it should be.

When I tried this earlier today, I did it for a fun climb. Now, this system beats knots as far as efficiency is concerned. It is faster to climb up, flipline in, then clip that carabiner up there to the saddle, throw one the friction hitch, and off you go.

Now am not arguing that this is an acceptable method. I am looking as an angels advocate. :angel: 

I'm looking for some proof here. If it's just people talking, then that can only be weighed so heavily.

love
nick


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## TheTreeSpyder (Feb 29, 2004)

In those universal symbols for climbing gear, i believe you will commonly see a symbol for not letting a carabiner leverage/sideload on a rock etc.

i believe they are made to hang free and be pulled straight on. Sideloading up against a surface can pull at the wrong angle for the simple structrual design that is made to only support on 1 angle of pull, not to 'defend' itself against all others. So sidleloading pulls at an angle that is rated much lower than the straight angle it is calculated to hold. i think one of the ways it does this is by isolating one leg, then compounding that by not pulling along the axis of that leg. So the structure is essentially compromised very much.

i think additionally, laying up against a surface that was not flat, or shorter along the length of the carabiner and flat especially (a carabiner against a flat/flat surface longer than the carabiner would prolly be pulled straight/correct and not count in this?); that the load on the line would become leveraged/multiplied in the carabiner. Furthermore, being squeezed flat against the support would induce more load even in a bowline, so this force is higher than the load, then this increased force is fed into the leveraged carabiner position in this scenario.

So that, the danger is, the compromised carabiner, recieves a leveraged/multiplied x multiplied load at a still load, then loaded more with the dynamics of bounce and movement. i think that is burning the candle at both ends; and can get you into trouble much more quickly.

i think loading across the gate is yet a different issue; and with these aforementioned compromises i am visualizing weaknesses imbued into the strongest part of the carabiner. 

Orrrrrrrrrrrrrrrrr something like that!
:alien:


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## Kneejerk Bombas (Feb 29, 2004)

> _Originally posted by Tom Dunlap _
> *Mike,
> 
> Jerry B. offered an explanation of the Bailey cover on Treeb*zz a while ago. *



I don't blame Jerry B., Bailey's used the photo which goes out to hundreds of thousands of eyes. I could see using the photo if there was some historical reference and bold explanation that this is no longer acceptable or even just lie and say it's a removal.



> _Originally posted by Tom Dunlap _
> *There really isn't a good reason to use a biner in a sideload situation when a running bowline or screw link would be better.
> 
> *


I agree, it's indefensible position to say it's only a little wrong so I'll continue doing it. Bragging about it on public forums where other impressionable young minds might expand it's use is much worse.
Just a few days ago RJS bragged about doing this very thing (side loading carabiners) when rigging smaller limbs out. Young Nick sees this and now he's climbing off this flawed system.

If you let one wrong piece into a system, then another, and another, they compound themselves.

To keep it opn topic, SRT puts bigger loads on the parts of the system, compared to doubled rope systems. Not that I would ever need a reason to do things correctly.

I see this as similar to the use of non-locking rope snaps, not staying tied in, spiking on trims, kicking brush into a chipper with your foot, etc.. 

I won't work with guys that ignore basic safety rules, period.


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## murphy4trees (Feb 29, 2004)

Nick,
Good point... there may not be a specific "rule" in ANSI about not side loading biners, however it probably says something like "equipment to be used as per manufacturers recommendations. It is important to look to our elders for wisdom... How long have the rescue people and cavers etc... been using biners.... Do you think they would accept the "I only weigh 155" logic???


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## NickfromWI (Feb 29, 2004)

When does the side loading become unsafe and begin so weaken the carabiner?

How much of a load do you have to put on it? Murph, you mention the cavers and mountaineers.... I've seen cavers, rock climbers and mountaineers do things that we'd be scared of. In rock climbing

What I'm saying is that carabiner is rated to about 5,000lbs. I weigh 155. If I did put 3x that load while footlocking, that'd be 620lbs. That's still better than a 10:1 safety ratio. 

Tom, why is it okay with a screwlink? Because it's smaller?

In Sherrill, they offer the idea for use on large wood. So where is it okay and where is it not?



And young Mike, please don't think I'm bragging..."look at me...I don't need no stinking rules!" When I look at the facts, it seems like this is a safe practice. When Rocky talked about in regards to rigging branches out, I thought about forces created while swinging, miscalculating the weight of the piece, rope-guy not letting it run as smooth as you thought...things like this that lurk every corner waiting to make something go wrong. In this scenario, it's straight up with very little dynamic load, no swinging, no ground guy. 

Could a person design a carabiner that IS designed to withstand that side pull? I think we need testing on this.

love
nick

*ANSI Z133.1 8.7.5
Carabiners used in securing the arborist climbing line and/or the work positioning lanyard to the arborist climbing saddle shall be of the self-closing positive-locking type with a minimium tensile strength of 5000lbs. Standard one-quarter-turn, twistlock carabiners do not have a poisitive-locking mechanism and shall not be used.*


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## TheSurgeon (Feb 29, 2004)

*A whole lot of whiners*

You know, I read these post over and over and most of the time I am trying to figure out why 90% of the topics are about peoples feelings being hurt. Most climbers I know of don't take a whole lotta BS from anyone and get angry very easily, that's how it goes around here. How about keeping the subjects on arboriculture and getting rid of the pacifiers. This site is o.k. most of the time, but it's starting to turn into romper room fellas.......


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## MasterBlaster (Feb 29, 2004)

Don't hold back, Surgeon!


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## MasterBlaster (Feb 29, 2004)

Did you footlock/whatever straight up the tree?


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## murphy4trees (Feb 29, 2004)

Nick asked "When does the side loading become unsafe and begin so weaken the carabiner?"

I really don't know.... Since I don't know for sure... I try not to side load my biners.... it happens from time to time accidentally... never on purpose... 

This kind of reminds me of a conversation I had with a bucket operator doing storm work in Va... He wouldn't hear about wearing a safety lanyard while aloft.... mechanical failure, big wood going the wrong way and hitting the upper boom, branch grabbing him and dragging him out of the bucket..... nothing worked.... So i told him about ANSI regulations.... he just walked away.


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## NickfromWI (Feb 29, 2004)

MB, That picture made me laugh! 

In real life, it looked like a normal tree with a good leader and a nice spreading crown. I footlocked up to my TIP.

Next time I'll try to walk up the back side....it might be faster.

love
nick

Surgeon...who's whining?


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## NickfromWI (Feb 29, 2004)

> _Originally posted by murphy4trees _
> *This kind of reminds me of a conversation I had with a bucket operator doing storm work in Va... He wouldn't hear about wearing a safety lanyard while aloft.... mechanical failure, big wood going the wrong way and hitting the upper boom, branch grabbing him and dragging him out of the bucket..... nothing worked.... So i told him about ANSI regulations.... he just walked away. *



Murph, this is kindof what I'm getting at. Tell me about bad stories you've heard, regulations and guidelines telling us it's a bad idea....any factual evidence that would lead one to believe it IS bad and should be avoided.

Right now I'm not convinced. I've seen my 'biners get all twisted up while climbing trees and rocks. They always hold. Are they invincible??? NO! But I am far from the limits.

Your story is of someone who is ignorant, is faced with the right info, but then chooses to remain ignorant. I don't believe I am being an ignoramus here. I got Mike telling me don't do it because it shouldn't be done. Tom says use a quick-link/screw link. 

I want to be educated. I want to know.

love
nick


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## rahtreelimbs (Feb 29, 2004)

It has been 2 mos. since I started this thread and I still have no desire to use SRT. I embrace a lot of new tech with open arms but somehow this just doesn't get it!


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## MasterBlaster (Feb 29, 2004)

+1


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## murphy4trees (Feb 29, 2004)

I think its worth asking.... I checked ANSI and the best I could come up with is 4.1.2 "proper use". I would think that would better be stated proper use and according to maufacturers specifiactions... So maybe it'll be best asked to those whom make the gear.... What kind of biner is it????
Ask them how much side loading is too much... Let us know...
My mind is open...


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## NickfromWI (Feb 29, 2004)

I've emailed petzl and am interested in what their reply is. I will surely let everyone know when I hear from them!

love
nick


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## RescueMan (Feb 29, 2004)

*Side Loading*

The only strength-loss figure I've ever come across for a cross-loaded biner is 40%, but there are too many variables to use any one number.

I see that Sherrill carries a lot of Petzl 'biners and every one of them will come with an instruction pamphlet that shows all the ways NOT to load a 'biner, including on the side. Some of that is they're covering their arse, but it's generally foolish to ignore manufacturer's recommendations.

And, of course, your margin of error depends on what kind of 'biner you're using. If it's aluminum, well they break all the time when misused. If it's a 65kN locking steel monster, they'll take a lot of abuse. If it's a type 2 autolocker (twist only), then the gate can open when it slides along a friction surface and that significantly weakens the 'biner.

And using it as a choker can put up to double the load on the biner, multiplied again by 2 to 4 if you bounce a lot when you climb. So, even if you weigh only 155, you could be putting as much as 1000-1200 lbs of load on that 'biner as you ascend.

If it's a 25kN (5620 lb) 'biner, and the strength has been reduced 40% by side-loading (3370 lb) and you're putting a dynamic load on it of close to 1200 lbs - the safety factor is getting kinda small.

So, can you get away with it 99% of the time? Probably. It's that 1% that's gonna hurt, though. Why take the chance?

Anyway, it's kinda like using a good screwdriver as a chisel. It might work allright, but that's not what it was made for, and a pro doesn't abuse his tools.

- Robert


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## MasterBlaster (Feb 29, 2004)

Good analogy there, Rescueman!


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## TheTreeSpyder (Mar 1, 2004)

i go with RescueRob's view, though i still think that there is a componenet of leveraging the length of the carabiner as the body of the carbiner jams against something as a pivot; whereby the longer the carabiner, the more of this trying to 'bend' the carabiner over something can be leveraged by the carabiner's own length. i would think a screwlink/quick link(?) has a maybe heavier construction for this battle, it would suffer similar dynamics. There are a couple of differnt positions the carabiner can lay in at this point, that would place this leverage at different angles of pull against the carabiner etc. i think per strength a shackle is shorter and beefier, and more up to these challenges.

So i still see a pull at weak angle of the structure of the carabiner, that takes on a load leveraged by the choke position of the line; then that increased force could be leveraged more by the stiffness of the carabiner's length 'bent' over the obstruction.

i think that you could construe a flat surface just as long as the carabiner, so that the pulls would come perpendicular to the flat surface from the back, and give side loading without the choke or trying to bend the spine of the carabiner over a 'rock' or other obstruction elements. So as seperateable conditions, i think that the side loading, choke leverage tension in line, then bending the carabiner over an obstruction need inspected for prescence and effect seperately in a system.

Due to the shorter and beefier length design/shape i think shackles would be better for this positioning, but the soft line not incurring the problems of the stiffness of the metal devices spoken of.


Orrrrrrrrrrrrr something like that,
:alien:


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## Kneejerk Bombas (Mar 1, 2004)

*Re: Side Loading*



> _Originally posted by RescueMan _
> *The only strength-loss figure I've ever come across for a cross-loaded biner is 40%, but there are too many variables to use any one number.
> 
> *



Robert, I think you may be underestimating the stupid factor here. Nick is not cross loading the carabiner, although there is always the chance he is doing that too. He's side loading it!


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## TheTreeSpyder (Mar 1, 2004)

Dang Mike too quick fer me again, here is mine anyway! Was going to delete my post , then add this as my work around, cuz if there was no pic in original post, then ya can't edit one in the way i understand it!


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## Lumberjack (Mar 1, 2004)

Spydy is right, the shortter the biner, the less leverage that can be placed against it, therefore the less side loading. 

That is why Sherrills caption says for use on wood over 2'. That way the arc on the wood is flatter on larger wood, thereby sideloading less. 

To me, a steel clevis, or a rapid link would be better suited to the sideloading. 

But on stuff under a foot or so, most needs could be handled by a 1" nylon turbular webbing, and is cheap as dirt to make, using a beer knot.


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## Lumberjack (Mar 1, 2004)

> _Originally posted by TreeCo _
> *
> 
> Why would a climber misuse the not backed up, single piece of gear his life depends on?
> Dan *







That summed it up. Was it that hard?



But I think that the thread has moved to what is the proper usage, and what if any sideloading is acceptable?

I would say a little less than not much on aluminum, and a little more for steel.


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## NickfromWI (Mar 1, 2004)

So sideloading is bad?

Yet, I am sure all of you would promote a running bowline. 

Yet manufacturers reccomend at least a 4:1 bending radius, and often much higher than that. The running bowline is a lowly 1:1

So why is it wrong to disobey the "rule" to not sideload, but ok to ignore bending radius?

I'm sure there is no one here using a 2" thimble for there half inch climbing lines.

love and open mind
nick


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## murphy4trees (Mar 1, 2004)

the yosemite tie off puts the running bowline at 2:1

the rescue folks consider it an inferior knot... which was a surprise to me.


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## MasterBlaster (Mar 1, 2004)

I bet my life on a bowline all the time.


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## RescueMan (Mar 1, 2004)

> Yet manufacturers reccomend at least a 4:1 bending radius


That's true - they RECOMMEND a 4:1 minimum radius to maintain the full strength of the rope, but they don't REQUIRE it.



> So why is it wrong to disobey the "rule" to not sideload, but ok to ignore bending radius?


Because the manufacturers say very clearly DON'T side load biners.



> the yosemite tie off puts the running bowline at 2:1


I'm not sure what you mean by this, but used as a choker any loopknot will bend the choked rope around a 1:1 radius as Nick says.



> the rescue folks consider it an inferior knot


This tends to be true, at least in the Fire/Rescue world where practitioners have little experience and even less hands-on time with knots. But it's not true in mountain/cave rescue with those who know their knots.

The problem is that (as some of you have said) the bowline is not an easy knot to learn or remember for newbies, it tends to be insecure when not under continuous load and hence needs a backup, and it can capsize and turn into a slipknot.



> I bet my life on a bowline all the time.


So do I - and I use it in rescue as well as in recreational climbing and caving.

- Robert


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## murphy4trees (Mar 1, 2004)

it can capsize and turn into a slipknot...
I've heard that before but do not recall seeing it happen....
If set properly what would cause it to capsize???
Would making a second loop make a differnce....
Spydy PMed me about the yosemite tie off not changing the strength of the knot.... I liked it because the tightest bend in the rope goes around a single line.... Add the yosemite and that bend goes around two lines.... but Spidy pointed out that that is not where the knot is loaded....


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## TheTreeSpyder (Mar 2, 2004)

From the lore of shipping docks comes the warning of inverting the bowline from the tail/'toggle' sticking outside the eye the bowline forms. In this position, the tail can snag on a moving load, inverting the knot. The bowline was used for centuries like this, availing to the fairly friction free transport of water connecting many places.

The half hitch/'bunny hole' ring of the bowline is the primary loaded arc/curve, and dictates the knot strength, and making this termed properly a knot. A hitch, needs a host, to wrap on; it is this host/post/another line etc. that have varying sizes, that sets the primary arc for a hitch. Therefore a 'knot' will have pretty much a set strength; but a 'hitch' (that needs a mount or host to be complete) can have varying strengths depending on the primary arc that the host it mounts to imposes. Whereby, slapping a bowline around 3 different size posts, will yield the same size primary arc in the half hitch that forms it. A clove to the same 3 posts, will have 3 different primary arcs, thereby strengths; as i understand the differance betwixt 'knot' and 'hitch'; though as ya go real small (fishline etc.), they call everything a knot, as i understand it.

So the Y tieoff affects the size of the loop around the standing part, not the size of the primary loaded arc of the half hitch, so does not give more releif/strength to the loading. A double/round turn/mountaineer bowline, gets a slight strength boost spreading out stress a bit by doubling the choking ring in number, not size IMLHO.

i'd been talking to Daniel about making the DBY (Double Bowline w/ Yosemite tie off); being stronger, so PM'd him to edit if he'd like; being kinda my fault perhaps. i make the DBY with the slipknot method, kinda a backwierds/counterintuitive approach (surprize, surprize ); that gives a view of how the knot could invert in it's simplest form, with 1 ring, tail outside, no stopper knot (that the Y tie off satisfies as well as 'cleaning' out the temporary eye formed by the bowline). 

Working the 2 rings to form to knot is easier, with the slipknot method IMLHO; it also breaks the making of the knot into 2 stages, one that can wait on hold; then the 2nd stage can be whipped on quickly, precisely when needed. The slip knot method was used for rescue of a concious victim on the side of a cliff that could only have 1 hand free, especially if they were afraid to lift legs to draw a roundsling etc. up to seat. Under arms is a good place for this short term, otherwise the arms can go numb/ get lazy from the bite of the thin line, and victim can fall.

i think that the bending radius strength loss is more for lines the increased dynamics of being drawn/cranked across a surface, not in a standstill inside of a knot/hitch. Really for braids that aren't reel stiff 8x is prefferable (10x for twisted, aramids/kevlar almost to that of wire at about 24x); but the 4x is accepted as more workable, with strength loss in the knot ranges ; so is 'matched' componenets. But a spliced eye on a 4x diameter pulley wouldn't be 100% strength IMLHO. Another factor is how the sheave/pully supports the 'belly' of the line (not just a deep groove, giving no support here). With aramaids real picky (as is cable) about this part of the design, regular rope pulleys not fitting the bill here for kevlar and cable.


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## Kneejerk Bombas (Mar 2, 2004)

*Side loaded biners*



> NickfromWI wrote, in part, on 03-01-2004 08:22 PM:
> *However, not a single person has shown that it is unsafe. I have read a bunch of people saying it is unsafe. But saying it and proving it are different things.
> 
> I am looking for answers and on this one, it doesn't seem that AS can provide that. *



Look at the sheet of paper that comes attached to the carabiner when new. It warns of side loading.
They are tested by pulling two ways, along the axsis and across it. They are not tested by pulling sideways as to bend the tool. They do not test them this way for obvious reasons, they would break at very low pressures. It would also be dependant on wether or not pressure was on the gate or parts of the gate. Using a biner this way could also damage it without you noticing it, only to have it fail when you need it.
If you want proof, clamp a binner in a vice with the jaws at what looks like the most vulnerable spot on the biner (right at the lower gate axis), tie a rope to it's top, and pull sideways. I doubt you'll need any more than your hands to pull it to breaking. This is not exactly the way the forces work in your set up, but it would establish an approximate sideload strength. 
I think we all agree the biner would be damaged at far below 5400 pounds, and even if you don't think it would be damaged at that point, it's not rated or intended for this use, therefore it doesn't meet ANSI's requirements when used this way.


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## TREETX (Mar 2, 2004)

*Re: Side loaded biners*



> _Originally posted by Mike Maas _
> *Look at the sheet of paper that comes attached to the carabiner when new. It warns of side loading.
> *



www.petzl.com/ProduitsServices/PS_338_1.pdf


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## NickfromWI (Mar 2, 2004)

Mike, look at the sheet of paper that comes with many climbing lines....the part where it reccomend (usually at least) a 4:1 bend radius. Then get back to me on why you can break that rule, but not the carabiner rule.

love
nick


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## TheTreeSpyder (Mar 2, 2004)

As Nick has reminded us before, internal rope workings can be like stange Voodoo.........

i think on braided lines working, cranking, moving over an arc for 100% strength efficiency, of a standard flexible line of polyester/nylon braid; that 8x the line diameter for the pulley is the standard recomendation. The pulley should be sized and shaped correctly on the bottom and sides of the 'sheave' to support the 'belly' and sides of the line properly, to screech this high efficiency out.

Conversely, on a fixed hang without being cranked and worked around that curve of the pulley and entering all those dynamics, i think that 3x rope diameter for the mounting, for 100% rope strength efficiency, same rope construction constraints is the standard quote.

Orrrrrrrrrrrrrrrrrrrrrrrr something like that!
Peace,
:alien:

P.S. Because i've been maid to agree with you no who again  in the same lifetime, i burden you with my favorite bowline and tying method....


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## NickfromWI (Mar 2, 2004)

From the New England Ropes webpage on Braided Safety Blue 16-strand arborist climbing line...

"Recommended D/d ratio is 8:1 "

http://neropes.com/arborist/default.htm

My concern, guys, is not so much if it's okay to use a carabiner in the aforementioned manner. Nor do I care about sheave size for our lines (Mike, you DO use a 4" thimble on your climbing lines, right?). The big question: When is it okay to stray from the reccomendations of the manufacturers?

Apparently we do it often. Some of you folks are putting up quite a fuss over the side-loaded carabiner. Yet, I get no straight answers.

love
nick


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## RescueMan (Mar 2, 2004)

*Rules and Recommendations*

Nick asked:


> When is it okay to stray from the reccomendations of the manufacturers?


Apparently you missed my post on the bottom of page 18 of this thread, or else you're just being ornery!

There is an enormous difference between a manufacturer saying DON'T side load a carabiner, and a manufacturer saying "for maximum strength, maintain a minimum of a a 4:1 diameter ratio for pulleys."

- Robert


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## RescueMan (Mar 2, 2004)

*Capsizing Bowline*

Murphy asked:


> If set properly what would cause it to capsize???



It's not only the "cowboy bowline" with the outside tail that can cause this, but a properly-tied bowline - even a backed up one - can capsize during a lowering if the half-hitch (the rabbit hole) gets snagged and dragged upwards, moving it above the bight around the standing part.

This actually turns the knot into a slip-apart knot, not a true slipknot, and it will fail instantly under load.

Spyder's pictures illustrate this well.

- Robert


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## TheTreeSpyder (Mar 2, 2004)

Thanx, never heard that before on the loop getting snagged! 

The bowline animated .gif i posted is of making a 'DBY' with the slip knot method(fergot to say that); making the same bowline knot with this backwierdz strategy is in itself an explanation of how the knot could invert/capsize IMLHO. That being said, i really don't think that making the finished bowline with this slip knot method makes it more likely to slip out the same way, it is just easier to see and view the mechanics i think. Also i think that the DBY comes close to 8 in symetry (easier on eye to quick check), strength, security; slip knot method darned easy to make. Especially when you want to get just part of the bowline made, then wait for something to be brought, stretched, swung etc. to you, to capture real quick in the 2nd stage with only part of the knot to finish. The slip knot part, can be achieved then laid aside, hung on thumb so you can use your hands, or on a stob, this holds especially well in wait for you to need it with the friction and rigidity of the 2 turns together rather than 1 i think.

i remebered where i got the numbers for the line bend efficiencies (well, some of 'em). Samson's Climbing Line Guide they used to give out on request; then later viewable/downloadable from Samson Rope Ruides . Some interarresting points throughtout the guide- a real must have IMO! It is even better than the previous, expanded 10 or so more pages, just for us!!

Top of Page 26, has a table of maximum rope strengths for bends, different on a pulley or on a 'pin' that i assumed (pin)when i read it before meant, just a hanging point/swinging? Not, turning on a pulley/ working across an arc, all kinds of dynamics going on internally, just hanging/swinging. If that is true, that would be like a knot i think. Taking that rule of thumb presented, the 2 line diameters the arc of the half hitch chokes gives approximately the strenght of the bowline i thought.

Bottom of Page 12, brings out a point about the type of knot termination choice to prevent sideloading the carabiner as much as possible.

Excellent, Excellent Guide IMLHO; so i won't say anymore now, unless someone can't get to it! Loads of points and discussions eminent i think.

i think a lot of rigging is about being the inspector and placing everything in maximum strength/minimal loading (umm unless you can inverse those properties, to your advantage  ) ; that is equitable as a habitual style, art, mental puzzle and exercise to be better at each.

Orrrrrr Something like that...
:alien:


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## Kneejerk Bombas (Mar 9, 2004)

I've been playing around with something new, to me anyway.
One time the SRT really shines is for limb walks. I came up with a way to cross back and forth from DdRT to SRT. Simply tie a midline loop in the running end, just above your hitch, and clip the standing end to it. Now your SRT. Do your limbwalk and when you get back switch back to DdRT.


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## Tree Machine (Mar 9, 2004)

*Clarification*

Diagram ?


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## Tree Machine (Mar 9, 2004)

I understand clearly what you mean. It's an excellent method for the DbRT devotees to 'give SRT a try', if only for a few moments, without having to set up a classic SRT rig. Give everyone a diagram, though, so everyone is real clear what you mean. G'job Mike. -TM-


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## murphy4trees (Mar 9, 2004)

Simple enough.... sweet idea Mike... reducing the amount of line a climber needs to move by half, while loosing very little of the benefit of the 2:1 MA, because there isn't much weight on the line...
That'll have to be included in the book!!!!
TM,
Its pretty much just the way MM said..
tie an alpine butterfly or other midline knot such as a doubled fig 8 or fig 9 just above your climbing hitch....
unclip your biner and spliced eye from saddle and clip to midline loop.... continue moving out the limb on the single line with same friction hitch... I like that one a lot...


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## Kneejerk Bombas (Mar 10, 2004)

> _Originally posted by TreeCo _
> *The only problem I see is that the carabiner may get side loaded pushing up against a limb as the climber limb walks. Or even a tangle with brush in the carabiner.
> 
> Dan *



That would never happen. 

If you start out where you don't have to decsend, and plan to return, no footlocking or pantin needed.


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## RescueMan (Mar 10, 2004)

*Just a question*

I'm always thinking ahead to a possible self-rescue scenario. 

Not that tree climbers ever fall on a limb-walk, but IF you did would your fine-tuned climbing VT (or whatever hitch you use) catch you in a shock-loading fall on single rope?

And, if it did, how hard would it be to climb back up with footlock and hitch on single rope?

- Robert


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## Kneejerk Bombas (Mar 10, 2004)

Personally, I'd footlock back up, or footbrake down to the next limb and re-acsend. Another option for me, is to use my lanyard to pull myself back up DdRT.
When ever I climb, if the swing potential gets high enough that I might injure myself in a fall, I safety in.


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## Kneejerk Bombas (Mar 10, 2004)

What's the best mid line knot for this?


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## Lumberjack (Mar 10, 2004)

I would say buterfly or the directional 8.


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## NickfromWI (Mar 10, 2004)

How 'bout a slip knot!


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## NickfromWI (Mar 10, 2004)

Here's a pic to show.....







If you don't like the slip knot, I'd say go with a Butterfly.

love
nick


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## RescueMan (Mar 10, 2004)

I'll often use a similar techique in rock-climbing when I get to a belay station and have to "limb walk" a ways from the anchor to get a better line of sight to my second whom I'll be belaying up.

I'll use a clove hitch to attach to the anchor 'biner. The fact that it cinches down on the 'biner makes it less likely that the 'biner will turn and get side-loaded.

- Robert


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## Kneejerk Bombas (Mar 11, 2004)

The clove sounds smart. Once you are done, you pull out the biner and the knot falls apart, no untying.


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## Kneejerk Bombas (Mar 11, 2004)

> _Originally posted by NickfromWI _
> *Here's a pic to show.....
> 
> 
> ...



What the heck is in that pan on the top shelf in the background??
I hope that's not your dinner!


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## NickfromWI (Mar 11, 2004)

Funny! I don't even notice that thing anymore! That's all the sawdust that I swept up after I got building my splicing table!

That's edible, ain't it?

love
nick


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## murphy4trees (Mar 13, 2004)

Nick,
Any word from Petzl????


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## Kneejerk Bombas (Mar 30, 2004)

I've been using the set up in the above picture more and more and I like it.
I want to name it, so I can be all cool like Tom D. He got to name some stuff, DEDA, is that right? 
Anyway I figured Convertable Single Rope Techinque, on account of you can convert back and forth.
So I name it CSRT.


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## Tree Machine (Mar 30, 2004)

*Ride a convertable*

That gets my vote... And now you're in the 'cool guy' club. 

I tried a version of your thing, except I ascend up a doubled rope, both ends on the ground. Instead of creating a giant loop and working below it, as with your fine system, I put in a midline butterfly in one of the two lines, sling and double-biner it to a local limb, and SRT off the remaining line.

Same as anchoring to the base of the tree, only the anchor point is up with me, in the crown. The sole reason for this is I find it far easier to footlock up into the crown on two parallel lines, rather than on a single. 

I'm going to call mine bSRT, bastardized single rope technique. I'm less pure, but a few moments faster getting up there. -TM-


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## Kneejerk Bombas (Apr 1, 2004)

I'm trying to get cool here, TM. Don't come in and dilute my moment by stealing my ideas.


Do you remove your hitch from the doubled lines and put it on the single rope, or tie a new hitch with a seperate cord?


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## Tree Machine (Apr 1, 2004)

I'm sorry. I don't use climbing hitches, except in demonstrations to show how 99.99% of treeguys do it. I'm the other .01%

I didn't mean to steal your thunder. Worry not, as we all you're amongst the coolest anywhere, even without having a technique named after yourself.

In answering your question, though, I get up to a comfortable place (ascending up a doubled rope with dual-handled ascenders). Then I flipline in, and set the rig. There is a moment where I am not attached to the climbing line whilst I change over from ascent to working mode. -TM-


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## Kneejerk Bombas (Apr 1, 2004)

What dp you use? Picture?


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## Lumberjack (Apr 1, 2004)

> _Originally posted by Tree Machine _
> *There is a moment where I am not attached to the climbing line whilst I change over from ascent to working mode. -TM- *




But you are still tied in with you flipline.


What do you use to work off of DdRT? A lock jack?



As for an update on my SRT usings, I have been using DdRT for most of my activities. On rec climbs I still use SRT, as it is faster to set up and faster to climb. Tom, have you found a SRT hitch yet?

For the last month or so I have been in nothing but hardwoods, mostly gum and oaks, and I have found that I like the 2:1 MA that DdRT offers. Oh and I am using a Swabiish. I need to order some sta set, so I can get my VT tuned up. However I like the Swabiish's short action, where you dont have to compress the braids to move the coils. 

For ascending high into a spreading canopy, I perfer SRT, unless the limbs are close enough to "walk" up them. On pine removals, I still perfer SRT as it is much faster for me.


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## Tree Machine (Apr 3, 2004)

*Horse of a slightly different color*



> But you are still tied in with you flipline.


Yes, always, Ascend up a dual rope with dual ascenders, generally to the first limb, though sometimes all the way up to my tie-in point (it just all depends). Flipline in for safety. Remove ascenders, rig into work / descent mode, do the treeguy thing.


> What do you use to work off of DdRT? A lock jack?


No, I do not use a lockjack. I borrowed one once to take it for a 'test drive', and though novel and well-designed, I found it painfully slow and imposed a number of limitations I'm not used to, especially it didn't allow me to flip seamlessly back and forth from SRT to DbRT-- that is DbRT as I practice it, which is two parallel lines, both ends on the ground.


> What dp you use?


 DP? Descending piece? It's mechanical, and I'll refer back to the opening thread, 15 pages ago....


> For the moment let's keep mechanical devices out of this and concentrate on hitches.


 -TM-


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