# training pics



## heartland (Mar 11, 2003)

At the risk of being severely ridiculed, here are some pics from the ArborMaster training I attended last week in College Station, TX. This was the first time I "blocked down" a bigger tree.

blocking down 

There are 5 pics. You will note the following:

-tired climber
-block connected via cow hitch w/better half
-rigging knots: half hitch w/ running bowline
-rigging line: 5/8" stable braid
-lifeline: 1/2" orange streak
-borecut

I have an mpeg of the piece going over, but not sure how to post it.

I'm glad to have the pics as they provide good review material. Amongst other things, I see how my body/cutting position could be improved....

btw - this was a 50' Post Oak that had died about 6 months ago.


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## TheTreeSpyder (Mar 11, 2003)

Very nice show, have been thinking of such things myself!

i might suggest 'marling' (?) cuts in the side for the first half hitch in the load to immediately be restricted by. Since you end up tieing in with lifeline right before backcut for 2nd/ failsafe support; why not do it earllier, even if you end up with 3 supports for a while.

i always like the line support off the load, especially for cutting face. i usually use a rigging line (not using it as only support, only help) and bring it up over the top, then serve it down the face side. After i use and disconnect from the line, i can have the guys pull on it (it is in most secure,braced position offering best leverage and the increased downward pressure on the hinge can make it hang on longer), this can make sure it goes to target and not to climber. But also if the backcut is carefully proceeded on, the line tension can be used to flex the hinge over with more fiber to hold on longer before free falling into the rigging. The most controllable part of force i see is not to let it build through accleeration (save cutting it smaller or untethered). So resultant force can be reduced hugely through reducing freefall distance previous to being caught by rig. If the tear off of the hinge can be stalled off from 1o'clock (from 12 vertical) to 3o'clock+, the force can be reduced by the amount of accleleration from the reduction in the freefall distance of the C.o.B. not the butt, so the numbers are real diffrences, increasing with length.

Less force, twangs the climber less, tests the line, knots, blocks, Porty's, slings, Karabs, groundies, spurs, awareness etc. less, offering more forgiveness to all.

But, all that is jsut IMH,AO, so no sweat, nice job!


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## treeclimber165 (Mar 11, 2003)

Some nice shots there, Tim. I hate to admit it, but roping down a spar like that gives me the heebie-jeebies. There's just something unnatural about it for me. I will coordinate the removal differently so that I can rope down most of the spar while there is still brush attached, and either chunk down the remaining spar in 2'-5' pieces or come to the ground and drop the spar. 

Having the ability to rope down 20' lengths of wood off of itself with you tied in above the block is quite a talent. I'm always afraid I'll get flicked off like a dirty booger.


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## Kevin (Mar 11, 2003)

Nice job Tim; I would opt for the marline as well.
What difficulties did you experience while performing this task and how do you like those little D's on a working belt?


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## monkeypuzzle (Mar 11, 2003)

Stay away from knots in the wood,make the face cut above or below the knot. The wood is supper hard. Swap hands on the saw or go to other side of tree for better cutting control.Hey, if it works use it right. I forget sometimes to slow down,but I am a speed freak and like to get done ASAP.Cool pics


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## murphy4trees (Mar 11, 2003)

Nice job Tim,
And a good teaching piece for those here at AS...
Holding that saw at shoulder level is pretty ackward.. especially when bore cutting... Did you use a back (strap) release or just start with a bore and move the saw back and around to finish the backcut???
I like to keep either my choked life line or my lanyard just below the sling, so there is no chance of getting bugger flung from the spar. Did the AM folks teach you to keep both above the sling???
Keeping one or both below the sling allows the notch to be lowerred to just above the sling, which reduces the distance the chunck falls, and thus reduces the force on the rigging. However if you do put your lanyard below the sling you could be trapped in place until the weight is off the block...

So thanks again for the pics and would you please share any thoughts you have about the AM training... Was it worth the time and money.. did you learn a lot?? etc..
Thanks and God Bless,
Daniel


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## TheTreeSpyder (Mar 11, 2003)

Daniel, there is a theory/princilple that the fall is the same, kinda an elusive conceptulaized deal of the the late Pete Donezelli(sp.?).

i think that both life connections above is safer, as that is away from the machinery works of the folding of the hinge and running of the line. The block snapping down can cut the line lifeline/lanyard, as well as the the running rigging line, so unless that life support line is in an extremely protected area under the rigg; i wouldn't use it for my failsafe 2 count while cutting.

Nice call on the ergonomics of positioning a bigger (or any saw)when cutting for better control, safety with less fatigue.

As well as i missed the knot in wood point, as far as resistance to cutting, and unwavering fiber flow in critical hinge machinery in the picture set; but hopefully not in actual practice! 

This is some of the most dangerous positioning/rigging/cutting i think, that tests all of your talents, timing, line lacing, setting, gear, groundies and control...... as well as spicnters! If Bri steps up and says he is wary of it (as i will too); i'd say it is non-novice territory fairly; and first tries should be coached, probably in non critical situations; and as always, preferably tied into another support than the rigging point (host spar).

K{no}w Fear,
and let Know-ledge Replace it!
(Sorry Bri, won of my favorites...........)

and since i first saw it and ever since; i must agree;
That Peace,
is Patriotic too!


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## murphy4trees (Mar 11, 2003)

*Donnezelli's point*

Spidy and all,
Donezelli's point is that the overall force of a chunk falling into a rig is determined by the weight of the chunck factorred into the distance fallen... That distance fallen is to be measured from center of balance (CoB) at start to CoB at finish.... Therefore the placement of the half hitches (relative to the block) tied to the chunck will not effect the fall of the chunnk as long as they are below the CoB..... However the placement of the notch above the block will effect the distance the CoB travels.... This is a crucial distinction to make when calculating forces involved in rigging down a spar.. especially with big wood. That's why I like my notch as close to the sling as possible... Another reason for putting life support below the sling.
As far as the block cutting a life support line.. now that is a point that is worth discussing... If the ropes are set properly there should be no chance of any weight coming onto the block until it is well below the life support lines. However as we all know... funny things can happen when cutting trees... So I'd like to hear other thoughts on the matter.. I believe Mark Chisholm teaches to put one or both lines below the sling... If I get a chance I'll take a look at some slow motion replays of the block's movement when rigging down a spar.
God Bless All,
Daniel


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## Kneejerk Bombas (Mar 11, 2003)

Nice pictures, and well presented, thank you.

I like to have one life line above and one below. If both are above, they are both subect to whatever causes them to fail, wether it booger flicking or accidental cutting. If both are below, then again, they are both subject to the possible problems associated with being below the block, like the sling slinding down, rope burning, or pulley interference.
With one rope above and one below, in the event that one of the problems occurs, it will only happen to one of the life lines, leaving the other to save your a$$.

I'm curious how you recovered your climbing line from way up on the spar, once you were ready to do the backcut.


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## heartland (Mar 11, 2003)

> _Originally posted by Kevin _
> *What difficulties did you experience while performing this task and how do you like those little D's on a working belt? *



There are times when I wish they were bigger, but for the most part it is ok.


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## heartland (Mar 11, 2003)

> _Originally posted by murphy4trees _
> *Nice job Tim,
> Did you use a back (strap) release or just start with a bore and move the saw back and around to finish the backcut???
> *


I use a back strap whenever possible... and cut it with my handsaw. If for no other reason, it is just safer to be making that last cut without a running saw in your hands.

*



I like to keep either my choked life line or my lanyard just below the sling, so there is no chance of getting bugger flung from the spar. Did the AM folks teach you to keep both above the sling???

Click to expand...

*AM teaches to keep all lifeline and lanyard *above* rigging point. They are real big on that.

*



So thanks again for the pics and would you please share any thoughts you have about the AM training... Was it worth the time and money.. did you learn a lot?? etc..

Click to expand...

*I've been to four of the AM training sessions:
-Climbing
-Chainsaw
-Rigging I
-Rigging II

All have been worth their weight in gold. Well worth every bit of time and money. Also get to rub shoulders with other people in the business and learn new things from them. 85% of our time was spent on projects: lots of practical training.


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## heartland (Mar 11, 2003)

> _Originally posted by monkeypuzzle _
> *Stay away from knots in the wood,make the face cut above or below the knot. The wood is supper hard. Swap hands on the saw or go to other side of tree for better cutting control.Hey, if it works use it right. I forget sometimes to slow down,but I am a speed freak and like to get done ASAP.Cool pics *



I hear you on the knots. I tried to stay above the one in the pic. One thing I learned on that one for sure is to position myself higher and further away in order to get better angle and reduce fatigue. You can't tell from the pic, but by the time I was done with that bore cut I was completely covered with chips... the dust was making me choke


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## TheTreeSpyder (Mar 11, 2003)

i've wondered about that same effect with the notch Daniel, just re-Peteing what i thought was said before on that. Thanks for defining that. i tend to pack the lines so tightly together if i have to, i beleive there is no loss of

Mike's point is well made. i too generally beleieve the D system, lines and anchor point on each of the 2 FailSafe tie ins should be seperate. On a perfectly vertical, smooth spar, without cutting cutting a protective double kerf to lay a line in that could be tough, this telephone pole scenario imagery is that which i was directly addressing without complications. Usually sight out a lean, pocket under spar knot/swell that is mechanically protected from either of the hazards of steel block slicing down into line, running line friction, or load grabbing. Another positive aspect is that, that places a line below the loaded support on the spar in weaker/ questionable tops. 

Very good discussion, i am rating it a 5, so that it will stick out to be refrenced by myself and others. Kinda reminds me to review a few of the other choicest threads and do the same; as i have let that slide awhile.


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## heartland (Mar 11, 2003)

> _Originally posted by Mike Maas _
> *I'm curious how you recovered your climbing line from way up on the spar, once you were ready to do the backcut. *



Mike - the pics don't show it, but there was actually a really long tail on that running bowline. All I had todo was pull on it to bring it down.

Interesting to know this too. Part of the AM training on this blocking stuff was how to get out of the tree (assuming you are leaving a tall spar for felling once on the ground). Of course, you could leave the running bowline with a tail long enough to reach the ground. But, another cool way was the following:
-tie in with your lanyard or other fixed positioning system
-leave your friction hitch attached to the climbing line
-remove the running bowline
-wrap tail of climbing line around the spar
-pass tail of climbing line down to the ground (this will be used to remove the system once on the gound)
-make a mid-line knot (we used butterfly) at the TIP
-attach biner to midline knot, then back to climbing line, above friction hitch
-cinch things up around the spar and you are ready to decend 

From there, you can either decend on your friction hitch or add an 8 and then decend. This system is easily remove by pulling on the tail. It is similar in fashion to the running bowline with long tail but was easier to remove simply because there was less friction at the TIP (due to the biner).


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## Jumper (Mar 11, 2003)

Neat pics!  and not worthy of ridicule IMHO. You look like you were having fun! Hopefully the tree was not all dried out or rotten, it has been my experience dancing out of the way of this stuff on the ground that larger chunks sometimes do not fall the way you think they are going to. It must be quite a Logistical nightmare to find "training aids" for a class-how many people were in it?? Did you all get a tree to work on???

I only wish such activities were possible here without freezing one's butt off at present. 0F this morning and another 4 inches of snow for tonight! My boss is still in snow clearing mode, so we have not done any tree work at all. Cabin fever is setting in!


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## heartland (Mar 11, 2003)

Jumper - thanks for the encouragement  

I did have fun. We only had 7 people in the class, which was odd because usually there are 10-12. That allowed for a lot of personal attention. One of your own, Dwayne Neustaeter, was the instructor. He is President of ArborMaster ® Training Canada, Inc.

Talk about a funny guy. Holy cow....... and a great instructor.

With the smaller class, we opted to all work on a single, large project: hence the 50' post oak removal. It was real brittle. In fact, two of the limbs actually broke during rigging operation. Not a big deal since we were all tied in. One of them occured while trying to get it setup for spider balance with two of us on the limb.... there were a bunch of Texas A&M students watching us on that one... gave them a bit of a scare, but not us: we were secure.

The other limb (smaller) cracked while a climber was resting on it. That one took us all by surprise. He got all twisted up in it with his lanyard but came out fine.


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## murphy4trees (Mar 11, 2003)

As far as saw positionioning I just noticed the AM ad to the left actually has some relevance to this post... the climber is keeping the saw about waist level.. it's easier to control and see what you're cutting when kept waist high... Also looks like he has a lanyard tied in just below the rigging sling and above the block and he's using a pull line.
Tim did you not use a pull line on the top of the spar?? Tough to tell how the tree was leaning from the pics.. and I like a pull line to make sure the chunk falls into the face... a pull line allows the hinge to be a bit thicker and thus gives it more control. That's another reason why I don't necessarily like the back release for chunkin spars... Though it gives the climber an opportunity to put the chainsaw away and finish with a hand saw... it pre-determines the thickness of the hinge, while with a conventional backcut the climber can only cut as much hinge away as needed and with good communication can still put his saw away and get braced before the ground crew pulls the spar over... 
This is my thinking on the subject and I Am open to learning. What was the reasoning given for keeping life line and lanyard above the rigging sling?? In the end I suppose everyone has to make up his/her own mind as to what technique he feels most comfortable with... 
God Bless All,
Daniel


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## tophopper (Mar 11, 2003)

great pics!!

personally ive always found spar work to be the most pysically demanding.
Just huggin wood, bendin, twistin, reaching.
I would have say it is my least favorite removal technique

good job tim!


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## Dan Flinn (Mar 11, 2003)

Cool pictures, Tim! Man, that was a big chunk! 

I havn't done a removal like that in a long time. Mostly just section the spar to a landing zone. I'm with treeclimber, rigging like that freaks me out! Call the crane guy!!  

Dan


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## Tom Dunlap (Mar 11, 2003)

Pete Donzelli, is the correct way to spell his name.

"All in all, it's just the same distance of fall" December '99 Arborist News.

Can anyone come up with the play on words that Pete made in the title to the article?

Tom-missing my friend


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## heartland (Mar 11, 2003)

> _Originally posted by murphy4trees _
> *As far as saw positionioning I just noticed the AM ad to the left actually has some relevance to this post... the climber is keeping the saw about waist level.. it's easier to control and see what you're cutting when kept waist high... Also looks like he has a lanyard tied in just below the rigging sling and above the block and he's using a pull line.
> *


Yup, next time I will definitely have the saw at waist level: I had to work too hard the way I had it in the pics (too high).
You are right about the AM ad on the left: looks like the lanyard is tied in below rigging... if that is the case, it contradicts what we learned. The rationale behind keeping both above the rigging point is simply to be away from the rigging. There is less chance of getting mixed up with the rigging when above vs. below.

*



Tim did you not use a pull line on the top of the spar?? Tough to tell how the tree was leaning from the pics..

Click to expand...

*No pull line used. In retrospect, it would have helped. Only thing to be cautious of when using a pull line is the physics of a "moment arm". Say your hinge is a bit too thick and the groundie on the other end really has to wrench to get the hinge over.... you end up with a lot of unneccesary torque. That torque energy has to be released somewhere: that "somewhere" will be the shaking spar. There is a fine line between all this. You have to balance things out.... If the hinge is done just right, the climber should be able to cut the backstrap and simply push it over - but in that case, a pull line should not create add a dangerous amount of torque.

btw - I left the backstrap and released it with my handsaw. Chainsaw was not running and therefore no noise to interfere with communication with my groundie.


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## Kevin (Mar 11, 2003)

"Say your hinge is a bit too thick and the groundie on the other end really has to wrench to get the hinge over"

You should never exert too much force on the piece from the ground.
It would be better to take more wood out of the cut.


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## mikecross23 (Mar 11, 2003)

Awsome thread Heartland!!! Good timing too! I roped down a spar today for the first time. Everything went great and I just can't describe how good I felt when done. I took small pieces about 6' long and between 6" to 16". My dad has been working for me when needed and he's gettin' the rope thing down. He let everything run with ease while another groundie pulled w/ tag line to clear the bushes. Good starter tree because even if I messed up, there were only some inconspicuous bushes below. I was a little slow but hey, give this rookie a break.

This is a great thread to follow up my day and stomp some safety issues into my mellon! 

Thanks Arbo Site folks.
-Mike-


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## heartland (Mar 11, 2003)

*Distance of Fall*

Guys - here is what it says in my AM training guide. I'm pretty sure this is straight from Pete:

"One variable that almost always can be controlled is the distance of fall. If the piece falls a shorter distance, there will be less kinetic energy to convert to stretch in the rope, so the force will be lower. The rigging block can be tied up tightly to the stem, and as close to the cut as possible (allowing room for the climbing line and lanyard), without compromising safety.

Some people ask if the distance of fall can be affected by the way the wood is tied off above the cut. The answer is no, as long as the piece is tied so it can't flip over. With the half hitch anywhere below the center, the disance of fall will be the same. The piece can't flip if the marline hitch of half hitch is below the center of the piece.

There are a few safety issues here. Knowing that the half hitch can be anywhere below the center of the wood, it is not necessary to try to place it down near the cut. There is a chance you might nick the rigging line with a saw, or worse, the half hitch might come off the end of the pice as it falls. Putting it up higher might also allow you to set a line above a stub or crook on the piece, to be even more certain that it doesn't come off the end."


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## rwilk (Mar 11, 2003)

great pictures, I own AM practical rigging videos and have found them helpful. I'm still waiting to do my first big wood rigging. Every time if say I'm going to rig a spar down, I end up being too tired after all the limbing, that I just fell the spar. I do have a large sweet gum that i have to do next week, and nowhere to fell it. I see about some pictures to post. 

good job

just my thoughts

rwilk


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## heartland (Mar 11, 2003)

Mike - give us the skinny 

-how did you tie in?
-lanyard and climbing line above or below the block?
-borecut or traditional?
-which knots?
-what size rigging line?


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## monkeypuzzle (Mar 11, 2003)

A 16'' x 6' stick, thats a big log dude. A great rope person is a MUST for this type of job,if you want it to be smooooooooth!


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## mikecross23 (Mar 11, 2003)

> _Originally posted by heartland _
> *Mike - give us the skinny
> 
> -how did you tie in?
> ...




The tree had a good lean to it so that kept the pieces far from me and made for simple cuts. I don't have everything I need to be safely efficient at rigging yet, but this was the perfect chance to get some experience. 

I tied in with a wire core lanyard and before making cuts choked the stalk w/ loop runner as secondary. I need to use my life line next time for critical situations, can't come down on a loop runner. Both were below a cmi steel pulley attached by a false crotch. I don't use my false crotches very much but I have two lenths and the shorter one fit perfect up top, but when it got thicker the larger one left some play in the system. With the hefty lean I just made one cut straight through. What's a proper cut for this situation? I did make kerf cuts just below the backside so the chunks wouldn't peel. 

Tied off with a running bowline and I guess it would be called a half hitch. Looked like your pictures.

I have a couple three strand 1/2" ropes. Good for the light rigging I do but I felt like I was pushin' it today for the SWL. 

I will be lookin' to get a good bull rope, block, slings and hopefully a porty soon! In the mean time I'll stick to the basics and learn a little before gettin' in over my head.

My old man enjoys working with me and has the time to devote to being my rope man when called upon. He's pickin' it up quick and I can depend on him for sure!

Let me hear what ya'll think.
-Mike-


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## mikecross23 (Mar 11, 2003)

> _Originally posted by monkeypuzzle _
> *A 16'' x 6' stick, thats a big log dude. A great rope person is a MUST for this type of job,if you want it to be smooooooooth! *



The 16" diameter was only at a few knotty crotches so for the most part the trunk was smaller than that. My dad did great letting them run to a perfect halt just above the shrubs. 

I guess this is getto, but I wrapped a beach towl around the base of a nearby dogwood and put some duct tape to hold it on. Only took 1 and 1/2 wraps to 2 and a 1/2 wraps for the bigger stuff.

-Mike-


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## murphy4trees (Mar 11, 2003)

Mike ...
You're scaring me....
What I think is you should always stay on a life line which can get you down in case of emergency..... that would be a choked climbing line here. Lose the steel pulley and get a rigging block.
Lose the towel and get a porta-wrap.
You already said you need all that stuff so just go out and get it... If you're thinking ALL that gear is expensive... you need to raise your prices.... A LOT!!!!


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## mikecross23 (Mar 11, 2003)

TRUE!


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## TheTreeSpyder (Mar 11, 2003)

*Re: Distance of Fall*



> _Originally posted by heartland _
> *Guys - here is what it says in my AM training guide. I'm pretty sure this is straight from Pete:
> 
> "One variable that almost always can be controlled is the distance of fall. If the piece falls a shorter distance, there will be less kinetic energy to convert to stretch in the rope, so the force will be lower. ...." *



Hands down i think the best way of doing that is delivering the load as far and slow as possible to the pretightened rigging on the hinge machine. Up, down or over, flexing on as much hinge as possible, gives most support and steering, on permissable arc dictated by faces. If a 16'spar tears off at 1:00 and starts free falling to the rig, that is a lot of force. But if you use a line like Daniel says in the highest leveraged position, and flex the hinge over with a wide face, with as much fibre as possible, maybe even violating the last few fibers with a handsaw (just to only severe as few as possible, to leave as many as possible), just till the groundies start tipping the spar over by pulling on the line. If the spar doesn't tear off till 3o'clock or so (sometimes 5o'clock, cutting the last fibres to release!)and free falling to riggin, that might have reduced the fall of the C.o.B. by 6'+; that is a lot less force. i beleive this makes more diffrence than notch size, rigging spacing etc.; i've refered to them here as another tweak; but believe the main prize is using the hinge machine to deliver the load as far as possible. i think that weight on the hinge puts 1x supported force on the spar, while weight on the rigging puts 2x supported force on the spar, inccreasing the reasoning of tweaking the hinge travel most, for the most support. 

These examinations i find to hold true on topping, rigging, felling and bucking; the hinge is the main controlling machine before tearoff, sometimes line aided. The perfection of design and placement of the hinge, walking the backcut to the precipe of failure, perhaps even flexing the hinge over with more force,when it has more fibre etc. is the main machine to tweak. For small weaknesses there, can annhilate much large advances in the rest. Of course all of that is better expressed in stronger, more flexible wood.

Well; i guess that is a pretty bold state-meant, but i guess i beleive it....... So, ready...... 

After that running the load to the ground, for another component of how much stress is put on the host spar catching it's top; is that it only incurs as much as 2x force as the rope brake resists. But i believe in minimizing the input force first, by using the hinge.


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## mikecross23 (Mar 11, 2003)

I know I need a real sling, but what are your opinions on me using false crotches today to make due?


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## rbtree (Mar 11, 2003)

Good thread and discussion guys; nice work, Tim!!

Duane is a number 1 great fella!!!

Have taken AM myself. The instructors are good for sure. However, I don't take everything they say or teach as gospel.

I also prefer to have one tie-in below the sling---but just above the block, so it cannot get stressed. It could be pinched by the sling sagging a bit, but that has never happened. I have often checked and found the lanyard to be reasonably free while the load is still applied.

I too always make the cuts mere inches above the sling to minimize freefall. 

Another way to reduce freefall is to use a Hobbs or GRCS. First, the ground men can really tension the line, which will automatically open up the backcut, and can darn near tip the piece over all by itself. Of course, they dont want that to happen and have to be careful whilst tensioning, as they are underneath while doing that maneuver.. Then, as the piece is in freefall and has briefly unweighted the line, a quick tug will take some of the slack out of the line. The man on the device has to be good, as instantly he has to be ready to let the piece run as it comes onto the line.

Now, all that said, I'm with Brian.. I hate catching wood!! Let em drop if at all possible, especially if the tree is dead or has any structural problems. And as most of you know, I love to drop 26 to 40 foot log lengths--- into spots not all that much bigger...LOL


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## murphy4trees (Mar 12, 2003)

"Making due" is using an 044 to fell a big tree 'cause you don't have $1K to drop on a new saw. So a 24" bar with a new chain will have to do...
Using a 1/2' line, false crotch and rescue pulley to rig big wood, in place of a bull line, sling and rigging block is not "making due".. it's breaking the rules... The rules are there for a THREE reasons.. SAFETY ...SAFETY...SAFETY
you need to get a handle on the math here... The taller a chunk dropping off the top is... the farther it's center of balance travels before being caught in the rigging.... Every foot the CoB falls adds the weight of the chunk to the force on the rigging.... That adds up to a lot of force and you were most probably exceeding the SWL of your equipment... the only question is by how much????

So what is the barrier to getting the right equipment in place????
A couple hundred dollars... maybe 300 on the outside... Just add that into the price on the next job.... If you don't get the work there is no harm done... if you do.... you'll drive home with some good equipment that paid for itself in one job.... SWEET!!!


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## Kneejerk Bombas (Mar 12, 2003)

Rb, that picture cracks me up. Have you gotten any better at knowing which side of the cut to sit on?

Daniel, is that a mullet your sporting?  Sorry, couldn't resist.
What are you calling a false crotch? Isn't that what a sling is?

Mike, Did you really use a dogwood? Around here, dogwoods are multi-stemed shrubs.
It sounds like you did fine. If you grunt(dad) let it run, very little loading occurs, compared to stopping it anyway.


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## mikecross23 (Mar 12, 2003)

I made one of those little "need to get lists" a while back and this is what I added up for rigging equipment. 

200' 5/8" stable braid $239
5/8" block $85
2 tenex eye slings [email protected]$45
Porta Wrap (sm) $120

for a total of $534.00. 

I will eventually get what I need, but for now I will turn down or pass on anything I can't do. Again this was just an attempt to test myself with no major dangers involved. Low and slow, although the chunks I took were a little large for that 1/2" rope.

Thanks for the advice murphy4trees,
-Mike-


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## mikecross23 (Mar 12, 2003)

> _Originally posted by Mike Maas _
> *What are you calling a false crotch? Isn't that what a sling is?
> 
> Mike, Did you really use a dogwood? Around here, dogwoods are multi-stemed shrubs.*



Mike,
I expected more ridicule from everyone about this than I've gotten so far, but the false crotches I used were buckingham 2 ring friction savers. Not ideal. 

The dogwood was about 8"-9" diameter at about a foot off the ground. Not huge for around here but not small either.

-Mike-


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## TheTreeSpyder (Mar 12, 2003)

Don't have to get everything at once. You can budget along; in fact building slowy can teach you more intensely and appreciatively of each step/device and it's individual principals and definitions.

Line is most expensive,can build to that. Especially when running the line to the ground with porty and block, where the strenght isn't needed as much.

i would go with Large Porty for more flexability, and get something to attatch it first. Then block and attatchment.

If one had serviceable 'scrap' pieces of 5/8" at ~10-25+' lengths, some shackles, and good knotting/lacing skills; cost of attatchments could be forgone for a bit too. The same would be true of 1/2", especially higher strengths (7k+), especially brought to basket formation lacings (2.5xstronger than chokes), just to lower tolerances/strengths. Roundturn/double/choke baskets give choke and strength at a cost of extra line, harder to chase slack out.

2 1/2" rings put a 1" bend in a line that the manufacturer says not to bend less than 2" loaded (1/2"). The friction savers 'bend' that rule for bodyweights i guess, but certainly not for impacting loads i wouldn't think.

Can also use block to 2/1 with friction redirect a load down.

A compression/tightening jig would be worth playing with too, especially if ya had some ol'junk to make one, kinda laying around......

Good Luck in your journey and fascination.


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## Irradicable (Mar 12, 2003)

Tim Trentadue,
Great pics! I would love to see the mpeg.

What is the rateing of the bull rope that you were using?
What piece of the rigging was the weak link in the chain?
Considering the rateing of all your rigging and it's age, what is the safe limit for your chunks. Who can do the physics math?

Weight of chunk
Dynamic load due to fall height and breaking rate
Rateing of rigging reduced due to age and use
Added safety margin

Dave


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## murphy4trees (Mar 12, 2003)

MM,
It's hard to believe that you, a staunch suporter of safety requirements, would approve of MC's method.... Really surprising...
Will somebody please DO THE MATH here

Green weight log chart @ 16"= 50-100 lb/ft x 6'= weight of chunk

force on rigging= [weight + (weight x # ft of fall, from Cob toCob )] - friction on lowering device. 

All that's got to add up to less than 10% of the tensile strength of each component in the system. And don't forget about the bend ratio of a small pulley on that 1/2" line.... would be 15% loss at 4:1, which would be a 2" diameter pulley.

My recollection is that friction from letting it run can only dissipate about 20% of the force.... CAn somebody verify that.

Even then, neither the FC nor the rescue pulley is designed for shock loading, and all components should no longer be used for life support. 

I've broken the 10% SWL requirement plenty of times... but not like that.

SAFETY FIRST!!

PS.. MM seems like we did a role reversal here... ???


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## monkeypuzzle (Mar 12, 2003)

I'm sorry Mike but you can no longer work on any trees here in Tally and I was finally was able to read one of spydermans posts; ditto what he said.... yes on the green tenex slings get a bunch. 

The closest near death experience for me was the mullet thing just today.


This is my favorite time of the year men,nice here in North Florida.


-OR you could do this.


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## heartland (Mar 12, 2003)

> _Originally posted by Irradicable _
> *
> What is the rateing of the bull rope that you were using?
> What piece of the rigging was the weak link in the chain?
> ...



Dave - all good question. I can answer a few:

1. Bull rope was 5/8" stable braid: rated at 16,400# (SWL=1640)

2. I'd say the weak link was the crappy block we had: a bit old and unservicable. Newer blocks provide ability to remove the sheaves in order to replace the bushings.

3. We used relatively new tenex eye slings to attach the block and port-a-wrap.... can't remember the rating on those.

4. I'd need help with the weight of the chunk. I'd estimate it to be 12' long and 18" diameter. Somebody with a green log weight chart can look it up for Post Oak and let us know.


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## mikecross23 (Mar 12, 2003)

> _Originally posted by murphy4trees _
> * Green weight log chart @ 16"= 50-100 lb/ft x 6'= weight of chunk. Force on rigging= [weight + (weight x # ft of fall, from Cob toCob )] - friction on lowering device.
> 
> All that's got to add up to less than 10% of the tensile strength of each component in the system. And don't forget about the bend ratio of a small pulley on that 1/2" line.... would be 15% loss at 4:1, which would be a 2" diameter pulley.
> ...



All of my calculations are based on the above statement. I will do further research before taking on any serious tasks 'cause I don't wanna squash me or anything! 

I guestimated the largest chunck to be about 400-500 lbs, remember the log was not a full 16" diameter all the way just at a few wide spots.My ropes tensile rating of 7,000 lbs should give me a 700 lb SWL right? Calculate the bend from the 2.37" pulley sheave at a 15% strengh loss and that leaves about a 600 lb SWL for my rope. The steel rescue pulley is marked w/ a 2,000 lb SWL. According to the green weight log chart info. that murphy4trees posted, the heaviest possible weight log I took was 600lbs. Force on the rigging. . . A ridiculously high estimate from COB to COB, 2ft, I think that would create about 1,200 lbs of downward force. Am I on track? Subtract 20% b/c it was allowed to run, and the downward force would be 960lbs.

With all of these calculations done against my favor. I don't think that I over exerted my gear too much, just maxed out. Not to mention I was looking for some hands on experience with heavier rigging then I usually will do. Had anything in my jerry rigged system failed, the only tradgedy would have been squashed shrubs.

Let me hear it, I really don't know what in the heck I'm talkin' about, but I'm learning and I need your criticism everyone.

-Mike-


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## TheTreeSpyder (Mar 12, 2003)

i think that the reduction in force can be much more than 20% all depending on brakeforce. If there was no brakeforce/line there would be total reduction in force on the host spar. As brake force is introduced by the porty x present load force would be force on porty connection, then that x2 for force on Frictionless(block) Redirect on Upper Support. As the load powers a 2/1 on the Block connection/supporting anchor.

i also think that, the main objective would be to not let the load accelerate, and snub whatever force you could into the ground, without overheating the line etc. The heat would come from speed x friction, and friction pressure x contact area?, heat would collect at thermal insulators (synthetics, wood) contacted and dissipate on thermal conductors (metals, some even oil filled drums) with aluminum being a more 'jealous' metal, grabbing the heat evenly throughout it (better in cooking evenly) to more immediately dissipate it from friction point; compared to steel that dissipates heat slower through out it and can have more of a hot spot at most critical point to keep cool (rope contact). The 2 friction points of heat build up would be the Contact at block and porty (save a loose hitching viloently slipping into place aginst itself and wood), next is the hands of the line controller, gloves are a must for positive and safe action, most likely point of failure a lot of times in the system.

The point that carrys the most load (block) is metal, and reduces friction too, at the most critical point of 2x load. Allowing the friction at porty to be ground adjustable, non spiraling, non rope fraying, heat dissipating, 1xLoad point-to better handle friction with less damage to the line and less heat due to less load at same speed. 

The trade off is that placing a frictional redirect to ground on upper support, lessens the upper anchoring support load, and also reduces the amount of dynamic area of line to take shock. So with pulley block back in the configuration,the support load raises, but there is more usable dynamic 'rubber band' for taking dynamic shock loads better. In self tightening rigs, i take the pulley back out, allow friction in for lower support loading, and have the desirable effect of less line to have to stretch for the rig to set itself, but then, not shock load at all- so i need less dynamic area of the line to share the shock, so no pulley is okay for both the dynamic loading as well as support loading decisions in that context.

For you will always have the weight of the load to contend with, the variable in the force formulae to address first (weight x speed) is the acceleration and the multiplier it introdeuces unto the ever present static weight of the load.

A bunch of that is all same as:

quote:
--------------------------------------------------------------------------------
Originally posted by heartland 
Guys - here is what it says in my AM training guide. I'm pretty sure this is straight from Pete:

"One variable that almost always can be controlled is the distance of fall. If the piece falls a shorter distance, there will be less kinetic energy to convert to stretch in the rope, so the force will be lower. ...." 
--------------------------------------------------------------------------------

in that the reason of reducing the fall, is to reduce the spead; thereby lowering the force; so i try not to let it accelerate in all cases except the few that, that actually helps, save short of stalling out so bad as fracturing pressure can build in a spar (partial cause of barber chairing?). Also in running the line after controlling speed therefore force, i also don't totally resist the total force of the load, for as many times inlife; it will only incur as much force as it resists; then that resistance (oops, almost, caught myself Brian! ) must equal that which it resists. The poor block is in the middle and has to put up with both of the warring guy's chit on either leg of it's line, so gets it from both ends,and incurs 2x force. Or something like that......

edit:- i think that resistant force of friction forces the system to realize more of the force of the load, so therefore increases line force to all points between friction and load, so how is it subtracted?.

i am of the school of thought that internal rope damage could result in a dynamically loaded line craking over a 1" bight with a static weight of 500#. Also second that the mentioned devices are not made for such loading, and have Rescue pulleys with bent sideplates to prove it!!

If drop to catch is calculated at 1/2Ton, line stretch and more run will usually result in lines not pretitghtend to that, or any other give in system. It would be buffered as line stretched, but still moving force i think.

Pulley diameter, rope efficiency is calculated on the diameter of the track the line runs on in the sheave, not the outer diameter of the sheave that is the advertised size; as pointed out to me by Mr. Joe.


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## mikecross23 (Mar 12, 2003)

> _Originally posted by monkeypuzzle _
> *I'm sorry Mike but you can no longer work on any trees here in Tally.
> The closest near death experience for me was the mullet thing just today.
> This is my favorite time of the year men,nice here in North Florida.
> -OR you could do this. *



FuzzyMonkey, I mean monkeypuzzle, 

Sorry dude, I'm here to stay!
Did you get a mullet today?
This is a great time of year here!
And last but not least, what-R U tryin' to do? Get me killed by puttin' crane ideas into my head. I've got a lot of experience to gain, plus I want to come watch/help you first.

I'm out,
-Mikey-


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## murphy4trees (Mar 12, 2003)

MC,
The measurement fron Cob start to Cob finish is bound to be at least as long as the chunck is... That is measure from the (level of the backcut up to tha CoB, before x 2) + distance from level of the backcut to butt of chunk after it's caught in the rigging.... It's got to be at least 6.... maybe 9 or 10'...
The force on your rigging was easily 4000-5000 lbs - friction on lowering device.
Hope that helps... Keep asking and learning..
God Bless,
Daniel


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## TheTreeSpyder (Mar 13, 2003)

In general i guess i'd go with Daniel there. If the C.o.B. is about 1/2 way up, then it pivoting from 12 o'clock standing to rigging holding it at 6o'clock with a tight line, no stretch; takes the C.o.B. from 1/2 way up to 1/2 way down, for total movement of 1 spar length. And that is with the butt ending up being held as high as the stump by the rig, not dropping an inch! But if the C.o.B. was low, that could be less, if it is high, it would be more. For 2x 3/4 length would be 1 1/2lengths.

But actually, wouldn't it depend on when tearoff was, and how fast the load was moving at that point? Then, when it was caught by rig, how much it stretched the line? So that if hinge carried slowly to 3o'clock or later before tearoff, it could be much less, especially with a low C.o.B.? All the force deliverd to the line will stretch an un-prepared (and rest of the system points)line for that load, so motion will continue as the dynamic elasticity of the line runs out, then whatever force is built/buffered to there slams into the static properties of the line, as yet another event in the chain of events, also placing that force on all resisting points in the travel of the line lacing.

i didn't know where the 2' came from either, but had plenty more to focus on.

Once again in my imagery; if the piece fell without being tied on, it would impact the ground, not a line or UpperSupport; so force to them would be zero. When you put a line and attatch it to anything, the more friction braking the load, the more any point on the line between brake and load is realizes the potential force of the load. If it only is braking 100# of force of 4000#, it only realizes that in the rigging system; likewise if it resists 500# of the potential 4k, then the system incurs the 500#; only as much as it resists, or that the friction brakes. 

If that friction is at the ground and a redirect pulley on an upper support, the LoadForce will power a 2/1 pulley machine against the support, but the increasing friction will dictate how much of that potential LoadForce (weight x speed) to be actually realized in items linked by the sytem. Now the braking friction can stall back acceleration and decrease potential force like that. But the refrence to subtracting friction from the force i'm not following. If friction/BrakeForce is on the UpperSupport rather than the pulley, friction will decrease force, on the control leg to the ground, thereby, lessening UpperSupport load, for if the pulley was there the holding ControlLeg would have to match the LoadForce to suspend it.

So the more braking frinction (that always produces heat), the more of the LoadForce that is made to be realized by all linked between the warring BrakeForce and LoadForce connected by the line, while isolating the offside of the friction device (your hands, or next device that heat from friction is allowed to dissipate from in between devices) from that part of force incurred by controlling the LoadForce. Kinda like, if you dodge a punch, you present no resistance and incur no force, you catch it in your hand, you resist it as friction does a load, and incur force. The more you hold your hand solid and resist, the more of the potential force of the total force of the punch you incur. If you punched some kind of spring board set to mechanically fuse/ give way and bend over at 10#, and punch it with 40#, it only incurs 10#, increasing the resistance, will increase the force incurred in the springboard system, so i see that the friction should not be a subtracted factor; for it's resistance increasing, is that which actually increases the incurred force up to the potential of the LoadForce.

This also means that the total force of punching the board with 10# force resistance is equal to 2 10# punches meeting head on, just as squarely as the board was met.


Friction/ BrakeForce can serve to decrease/subtract force over the whole scenario, by decreasing/halting acceleration.

If the pulley is on the upper support, that support system, incurs 2x the ResistedLoadForce (ControlLeg of system must match force resisted of LoadForce's potential as dictated by BrakeForce to suspend with pulley). Take the pulley out,and make that a frictional/braking UpperSupport, it now dictates how much of the LoadForce is realized on line between UpperSupport and load, then pull on control leg, so any of it's force is added to ressited force from UpperSupport, but not incurring the force that the UpperSupport resisted. So that the Upper support load will be the amount of ressited pull of the LoadForce on the load side of the support + the pull on the control leg providing additional resistance to LoadForce. Or UpperSupport incurs 2xRessitedLoadForce - friction on the UpperSupport; if the UpperSupport is non-frictional (pulley), then it incurs 2x ResistedLoadForce, but if it has friction (no pulley), then that friction reduces the pull needed by the control leg, therby now reducing force incurred by UpperSupport , all the way to the point, if the BrakeForce on UpperSupport = LoadForce (tied off to overhead branch), UpperSupportLoad will equal LoadForce, for there is no control leg pull. But, system now must take the full LoadForce till something fuses out and stops resisting. Or something like that!


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## tjk (Mar 13, 2003)

so are you saying that you would rather rig down without a block and use just the rope and tree in order to increase the friction and reduce the force on the load / tree.


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## Kneejerk Bombas (Mar 13, 2003)

There are some large forces when chunking down a spar, nothing a 1/2" line couldn't handle in the discription of the work mike was doing. Murph's 4000 lbs figure might be generated with steel rope, 0 friction FC, and 100% braking. In mikes scenerio, we had fairly high friction FC, stretchy rope, and a groundman letting it run.


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## murphy4trees (Mar 13, 2003)

A good reference here is "The A & S of Practical Rigging", Capter 7 Understanding rigging forces, pgs 122-127... 
The law of conservation of energy creates a situation where the only way force can be reduced in any given rig is through elastic energy (stretch in the rope) and friction which converts the energy to heat...
Pg 127 gives the example of a dynamometer test where a 650 lb piece created 4,554 lbs of force on the rigging point while letting it run....

a 631 lb piece that was held tight created 7,326 lbs of force on rigging point....

no mention was made of how far the pieces fell before being caught in the rigging... which would depend on how tall the chunck was and how the rigging was set....

So I guess by letting a piece run in optimal conditions the force could be reduced by about 40%....


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## mikecross23 (Mar 13, 2003)

One more time. . . 

I love this website! Good thread to help me understand my ropes and forces I may apply to them. When I have more time I will come up with some more questions to help give me a better understanding. I also need to get some educational materials on rigging before doing anything serious where real property is involved.

Can someone re-explain the COB thing. How do I find the center of balance? From previous responses I concluded that the COB would be the center of the distance between the block and where the rope attaches to the piece to be rigged. I guess I'm wrong. 

Thanks,
-Mike-


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## heartland (Mar 13, 2003)

Mike - in an effort to KISS (keep is short and simple), here is my layman's explanation of CoB:

The point where the log would balance if it were laying horizontal.

Bearing that in mind, go back an look at my pic where it is tied off and you will see that my knots are well below the CoB. The "Distance of Fall" info from Pete in the A & S of practical rigging (I quoted it earlier) states that as long as the half-hitch (or marline, whichever you prefer) is *anywhere* below the CoB, you are good..... just don't want it so close to the hinge/cut area that there is risk of it coming off as the piece goes over.

If you go above the CoB, there is chance of the piece "rolling out" or doing a somersault.


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## mikecross23 (Mar 13, 2003)

Thanks Heartland, 

I was trying to make it way more complicated than it is. That's common sense. 

-Mike-


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## TheTreeSpyder (Mar 13, 2003)

C.o.B. CenterofBalance is where it will seesaw balance horizontally on a vertical pivot (from under or above), as TimT. says. It defines an awful lot in all of this, sometimes is the most important thing to spot out.

The hinge is the pivot (no rigging here), and the C.o.B. is the point that you calculate pull on the hinge from etc. This is the input power of the machine, how much leverage you allow it to take on your rigging, is dictated by PivotPoint to C.o.B. relationship.

Hitch is below C.o.B. so that hitch pulls closed positively and half hitch to, if C.o.B. is below leading 1/2 and running bowline then the lacing could pull open. The final position, would be C.o.B. between half hitch and running bowline, this will be sloppy and not positive.

TJK- Balancing that strategy with tree damage (bark,cambium damage in non-removel of support), loss of dynamic load area (less rubberband to any shock), undissiapated heat buildup etc..

It is tradeoffs per situation, more shocking needs more line area to absorb, so pulley gives that. Weaker UpperSupport might not handle increased loads of pulley, add friction high and/or other supports. Or put pulley back in and commit to running the load, to pull less on system.

It all depends, on all componenets and elements, assesing what you have and how many routes you can take from that point, what you have time and gear for and you dream is maximum. 

In many things i go for high friction on UpperSupport, to decrease the amonunt of dynamic line area, which also decreases the amount of line i need to stretch, as i am trying to get the line to prestretch itself before tearoff automatically, to it's own specification; thereby eliiminating most buildup in force, by handing load off to line gradually, rather than dropping the load into the line. For, if i pre stretch to 435#, and load is 500#, very lil dynamic loading, drop etc., which also helps to lessen SupportLoad, as well as the high friction. 

It does that as it builds resistance to load as line stretches, just as it takes 10#pull to resist 10#pull, so i place that pull at a high leverage point of the load just insside the C.o.B. (making almost perfectly balanced seesaw 1stclass lever, when line provides firm enough support to be a pivot), and slowly cause the hinge to begin to fail. If i can get the load to move from a second class lever pivoting on the hinge and controlled by the line, and rearange that with loading to the point that the line is the pivot; and faairly well balanced load, so that the lins is pivot and hinge is control!!!! After tearoff the hanging load will always be a 1st class lever, before tearoff, generally a 2ndclass lever. If i can cheat, and get a fairly balanced load to slip from 2nd class lever status, to 1st class lever status before tearoff, almost magic is possible. i am answering a question to the images and theories i've presented, that wasn't in the focus of this post, i am speaking now of overhead support, not catching a top from underneath on it's host spar. If i can get that pull to high leverage on the load from the side, the pull of resistance from the tightline can pull it around. The length of spar from the hinge to hitch now doubles as a pivoting reach to move the hitch right under the UpperSupport before tearoff, so there is no force from swing to that plumb bobbing point. 

Iff at tearoff the hitch is between you and UpperSupport then load swings away, iff at TearOff UpperSupport is in between hinging and LoadHitchPoint then load comes back at you. In betwixt, iff at tearoff LoadHitchPoint is in the 3rd scenario or lined up under UpperSupport at TearOff, then no swing. C.o.B. outside of Hitching on load, pulls hitches closed, puts softer green forgiving end down first, and lifts stob up at tearoff (towards chin away from roof) if unimpeded..

i break levers into 2 classes, pivot in between input and output forces (seesaw) is 1st class lever. Otherwise (pivot on either end) non1st class. If a nonfirstclass lever increases power/loses speed, it is 2nd class by the book. If nonfirstclass lever, and gain speed/lose power therefore 3rd class lever by the book.

In a non 1st class lever, seeing as the pivot is on the end, the system is more space efficient for what it does, place the pivot in the center and the same trick takes more space, but the trade off is in the write situations, a 1st class lever can do some of the work by balancing the load, for one side is the ballast.

We were lifting logs onto a heavy equipment trailer for someone the other day, puling with a truck to overhead pulley. i showed the guys on that crew, not to hitch the load at the end, it takes more clearance and hard to manipulate. Hitch near center, length above hitch point rides free, you don't have to lift higher to clear obstacles. Also in arranging the logs and seating them, if they are hitched close to center, the light side is trying to help you lift the heavy. So, they start lifting and guiding and thought that was okay. But i wasn't happy, that puts you straining and under the load. i hung on the light side, that picked up the other heavier end, they drifted like magic into place without me lifting. If something went wrong, you are more likely to fall clear too. then we put tag lines on the light ends, and that was safest, best.

Now if fly weight here can pull down on a spar and spirit the other end around, so will/same as moving a load into 1st class position before tearoff, as the hinge has more holding power than me to balance the heavy end and sweep it around. Close to the C.o.B. hitching, pulling on the farthest leverage point (hinge position at end of log).

im sorry some of that goes back to the wheel barrel. Before lifting into position, the C.o.B. is between lift and the pivot of axle on ground, harder to work. Lift it further/ rearrange weight to put 1/2 on the opposite side of the axle, and the C.o.B. is now over the axle. And it is easier to work, the axle carries the weight, with deft balance from operator, as the weight has now shifted and the axle is under the C.o.B. and load is floating along, one side balancing the other. move the C.o.B. out from you some, almost no effort, but handles push more positively against your hands, for deft control, like tree rig with C.o.B. just outside the hitch point.


Or something like that

Brother Daniel, i'm still thinking that if you set up your rig, and i stupidly forgot to hold the line or put it into the porty even, you cut, and nothing hung up, that running load would put less than 60% pull on UpperSupport; 3 raps, forget to hold more force, but with an real loading, and no hanging up still low resistance, line flying etc. i really think that, there is no force on system, that system doesn't resist. Kinda martial artsy/ Zen, but both physics and philosophy life sciences? Whereby, every action must have an equal and opposite reaction i guess i am saying (wow did i just make that up?); without resistance to the force, the force can't be invoked. It can be present, it can blow by, but only things that resist it, will incur it; a sail more than a screen, a tree with leaves or same tree in dormancy etc.

i think that the braking friction would be taking force out of the load, but placing it on the system in trade, i think that running a load can get it away from climber, keep load from accelerating and gaining force, direct to ground; sometimes snubbing out the last part of force into the ground like a cig butt. Any could not go well or at maximum, depending on the tweaks.

i totally agree that the rubber band (stretchy nylon) and how much of it is available before friction, to share the absorption of the dynamic loading is of top consideration after minimizing the amount of force that is handed to that next factor. In dynamic loading, i think that within a line's range, that dynamic lines properties are more important than a static lines strength. But in static situations of tight rigging a static line's rating, or strength rating or a dynamic line pushed/stretched to it's static characteristic range per the load would lead. So situation dependant.


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## tjk (Mar 14, 2003)

I disagree will high friction rigging. With low friction on upper supports I can make those supports stronger then they are by increasing- decreasing the angle of inflection-deflection by using multiple anchors. You talk about pretentioning the lines, How can you do that with added friction. It will take MORE pull to aquire the needed resistance. Plus with False Crotches we can put anchors anywhere we want. Now If a load is cut and suspended over an obsticle the ground crew will have to pull it out, if it is rigged with high friction they will need to pull more than the load weighs. Plus you have more force on the tree than is nessasary. I have been doing this for years, and have seen it done by other well respected climbers. I just do not understand how friction can help with rigging in any way. Another thought if the rigging line is in a high friction set up it can be difficult to drag the line around the tree. you have to pull a bunch of extra weight around with you, and that seems counter productive. I would like to hear more about your thoughts, but for my sake try to use terms we are all familiar with. I'm just a tree man


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## Irradicable (Mar 14, 2003)

Wow TreeSpyder, 
I can't belive I read the WHOLE thing!  

My previous questions were directed towards Tim Trentadue not mikecross23. It appears that the piece that he dropped in the pics could have weighed as much as 1200# and fell as much as 4' cob to cob. That's if you measure from the half hitch from start to finish with no stretch included so we would have 4800# of force (correct me if I'm wrong) x 2 on the pulley for a total of 9600#of force. Tim said that the block was most likely the weakest link in the chain of rigging, but what about the splice at the top of the block?

I have always found it safer to just climb a little higher and cut smaller chunks but it would be faster to know what your rig is capable of handling safely and not have to worry about where that chunk is going to fly off to when the rig parts!  I imagine that is what Tim was in the class for in the first place.

Dave


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## Irradicable (Mar 14, 2003)

Tim, 
How far away from the Port-a-wrap was the groundie standing? Was the Port-a-wrap attached to the base of the spar you were working in?

Thanks for the math work Daniel.

Dave


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## heartland (Mar 14, 2003)

Porty was attached at base of the spar.

Groundie was about 20' out. If I can figure out how to post the mpeg, you guys could see it all (anybody have suggestions, let me know). He did a real nice job of letting it run. There was very little shock load to the tree.

That is the goal of all this and what AM stresses throughout the training: reduce the shock loading to the tree.

I've got other pics where we setup a fishing pole that I'll post when I get time. Probably make that one a separate post since it focuses on another rigging technique.

Throughout the training, we employed speedline and load-transfer rigging too. Load-transfer rigging is a really good way of reducing loads on the subject tree.


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## murphy4trees (Mar 14, 2003)

tjk,
I have been trying to wrap my mind around Spidy's method for some time and have come to the conclusion that he is years ahead of his time and as such many of his techniques seem counter-intuitive to the way progressive arboriculture is being done...
His posts on triangle hinges got me re-reading Dent and together have bumped my felling technique up a few notches... Again from something that seems counter-intuitive and yet it REALLY REALLY works..... So I have come to trust this man's knowledge and experience as he so generously shares here... 
I also believe we are actually developping language as we name and write about these principles of treework... So it is often challenging to express in writing what we know and work with every day... So yes Spidy can be difficult to "digest" and may turn many readers off.... yet there are some wonderful nuggets available fro those whom are willing to think out of the box...

As to Spidy's high friction riggging technique.... I think it has merit especially for those that don't have a GRCS.... I think the tool is well worth the money even though I haven't bought one myself yet... So here's the way I understand spidy's high friction rigging...... 1st the groundies "sweat out" the slack from the lowering line system. I think there is a thread on that around here somewhere... Then he makes the cut in such a way as to have the limb slowly move it's weight onto the line... 
So by the time the limb actually tears off the hinge the majority of it's weight is already on the line... thus the line has been pre-tensioned.... The high friction at the overhead anchor makes less line in the system that needs to be pre-tensioned. So a huge part of this is in the cut.. He uses the triangled hinge technique to make the limb move horizontally.. so it slowly sweeps under to overhead anchor... You've got to see it to believe .. This is more like ballet than tree surgery...
And there is probably something about the center of balance of the limb that comes into play.. I Am still working on that.. Also at tear off the climber needs to be aware of the limb kicking back at him... If the groundies are paying attention, they let it run as soon as the arc of sweep is complete.. and probably before or just at tear off.
I still have yet to experiment with this in the field.. and plan to do so at my earliest opportunity...
Hoep that helps..


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## TheTreeSpyder (Mar 14, 2003)

It is sometimes hard to see thinking in a circle of how to pit something against itself, few twist and turns i guess.

Realizing the trees and their brethren as the giants of the earth, puts us as the ants to these matchsticks. One source of power for overcoming them, would be to pit their mass and reach against itself. Using the mass as power (as we release it) and the length as leverage. Tthis turns the tables so much,that what isn't quite possible at 8' is gracefall motin at 15' length! To name all components, call them out, and strategically force more to stand on your side than against you, to turn the tables on the giant. Part of this is assembling strategies that the same choice functions favorably in several ways; and thru diffrent changes in mechanical status of the functions.

PreTightening- i sweat tension into high friction like a MF'r, then cause the spar to set the line tight as it tips down. The longer the length betwixt the hinge and the LoadHitchPoint, the more leverage to set the line! Also the more support the line gives the spar, so the hinge can hang on longer, for more pre-tightening before tearoff! 

One very powerful technique for repeated pulls to same dleivery zone is a round turn on the support, and a karab with a leash on the belly of the turn. The remote karab contorl can be a release for removing the line or sweating it in. Set running bowline to half hitch, sweat in from leashed karab, sometimes impacting with bodyweight as guys pull. Impact like you don't want a log to impact a line(with proper support)! Especially a speedline, turn that all around, and impact to sweat in tight. If the round turn slowly traces back to less levraged pull on the tree, strength of system is increased. Another remote sweat location is between upper supports.

The restriction of the line on the load is a pull back, so the longer length from hinge to hitch also takes more leverage over the C.o.B. to deliver that pull to, that same length becomes a balalst to the heavier end at tearoff, for it is in 1st class lever status then, taht same length itwill also help ballast and float the head around, sometimes buteterfly light if 1st class lever is achieved before tearoff.

All this can be done and support load reduction too with high friction. But it also restricts the amount of line that can share a shock, so i don't load like that, unless i determine low class enough or...... proper flexability and strengh in Upper Support(s).

Compound this with a side sweeping swing dutchman, self torquing rig etc. and more and more things add up on your side.

edit, Very good Daniel, gives me hope that i can convey this that i have kinda talked about on the other boareds and here etc.


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## tjk (Mar 14, 2003)

The trees around here are often wider than tall with many urban obsticles. In most of my rigging the limbs need to be lowered in the vertical position besause of those obsticles. So we imploy multiple anchors with the least amount of friction as posiable that way we can lift the limbs untill the load is under the anchor by using a good hinge and a but line to protect the climber and for the ground crew to pull the load where they need to. By reducing the friction I feel we have gained greater control and have limited shock loading to a minimum.


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## Irradicable (Mar 14, 2003)

I didn't mean to imply that TreeSpyder didn't know his stuff...just that we are getting a little off topic. We started with chunkin' down a spar on line and now we are lowering into a overhead rig. But even then all comments are appreciated.  

Dave


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## mikecross23 (Mar 14, 2003)

Threads die when they don't stray a little. Oh well. 

-Mike-


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## TheTreeSpyder (Mar 18, 2003)

> _Originally posted by murphy4trees _
> *And there is probably something about the center of balance of the limb that comes into play.. *




i think that everything you do felling a tree makes a choice, gives mechanical instruction to how the force and direction of the C.o.B. is handled. 

With the shape of the tree, riding along that path around the force and direction of the C.o.B. as the force charges on.

And extending into climbing/rigging as all else does.

The footprint/shape surrounding the C.o.B. is ushered by the hinge to pivot the C.o.B.'s gravity-force and other applied pulls/pushes, to the balance of their compromise until such duties are discharged from the hinge at TearOff.

EveryTime.

IMHO

:alien:




:Eye:CounterIntuitive hmmmmmm; guess that might fit buddy, for well in rigging, other problem solving as in joking around; i try to see all sides of something (quickly, so that the other guy doesn't get my lil'butt!), even to the point of men-tall exercise. Usually not forgetting the way solutions, jokes can be found on the flip side!! Looking for that way of aligning everything so it's impact is metered and focused with desired force to target. That puts improntu artists like Johnathon Winters, Robyn Williams at the top of problem solving capability, for how many sides of sonmething that they can look at quickly and draw out a linked flowing 'assault' with maximum force to target, thinking moves ahead......... like a chess game.

That especially works well with trees as many things are that reverse 'twist'. 50# doesn't fall cuz 50# of pull is exerted automatically back by a line restricting it. So you have float. A Left side leaner, has a LeanSide to the left, but the ControlSide that tries to automatically meter enough force to balance the lean's pull is quielty working the hardest on the FlipSide of the 'joke', or CrossAxis of support, you cut a tree from one side to release it to the other. etc. 

So a lot of times here the hardest working part/solution is silently waiting on the extreme FlipSide, as most leveraged position against force.

:alien:


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## John Paul Sanborn (Mar 18, 2003)

So what do the Kramer people think of the GRCS now that it's been in the inventory for a while?

I too am a big believer in frictionless rigging, especialy when using The Winch where lifting and or pulling may be involved in the work. 

Old school methods of high frition rigging are still applicable, particularly when the climber is self-rigging. IMO tools like 8's are harder on the ropes then bark, because of the bend radius and rope-on-rope contact. 

Another situation I like to use friction in the system is when there is a load transfer being done with a tag line on The Winch. So the tag is friction free and the lowering line has some friction in it to assist in holding the load.

My point is that I never say never with old school operations (well there is that spar removal thing Ox did...) because they still have their usefull applications from time to time.


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## TheTreeSpyder (Mar 19, 2003)

Here is an older pic showing how to yave highfriction and sweat in super tight, with better support, higher friction, lower loading.

Then slowly lever load down into this on hinge. Get it down well enough, it provides so much support, that if tied near C.o.B., heaavy green end can't leverage as well against hinge. It can be so light on the hinge, that you don't need to hinge, if ya get it right. But i like playing and examining the machine of the hinge,a nd consider it more positive, that i hinge about all of the time.


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## TheTreeSpyder (Mar 19, 2003)

Set everything tight.


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## Nickrosis (Mar 21, 2003)

> _Originally posted by heartland _
> I have an mpeg of the piece going over, but not sure how to post it.[/B]



Have you found a place to host it, yet? Otherwise, e-mail it to me at [email protected] or [email protected], and I'll gladly put it online for you.

Nickrosis


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## tjk (Mar 22, 2003)

I do not mean my way is the best way or the CORRECT way this is tree care and there is no abc text to go by. My point is that the style I use has worked VERY well for myself and of course many others. With the Multiple anchors I can make the tree stronger than it is I can take large loads into small host limbs by compressing the limb instead of pulling it down but I do have an open mind. The problem with the friction is my ground crew usually yells at me for creating friction because it makes it difficult for them to control the lines because of the inconsistinsy of the force needed to acomplish what ever the situation was. Plus it is much harder for them to pull the load over obsticles. JPS, we have owmed a hopps lowering device since 89' I with I had purchased a winch a long time ago its the best, as the saying goes you get what you pay for.


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## Nickrosis (Mar 25, 2003)

Check out the video (7MB):

http://students.uwsp.edu/ncraw045/block_down.mpg


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## Kevin (Mar 25, 2003)

Nickrosis;
Were the students instructed to take a piece that large that close to the ground or were they managing the job themselves?


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## heartland (Mar 25, 2003)

Kevin - I am the student  

It was part of our exercise todo it that close to ground.


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## heartland (Mar 25, 2003)

Dan,

The guy in the background said "as soon as it broke, I ran out of space..."

He was refering to the viewing area of his camera not being able to capture the piece falling over.

Nothing failed in the system.


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