speed/lowering line combo

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murphy4trees

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I just used this rigging combo to bring the top of a dry ash out of the woods yeaterday. The lowering line was set high in a tree back in the woods, right over the work, and the porty set on the other side of the fence in the backyard. The top, which was hung up in another tree as a leaner, was tip tied with the lowering line. Then a loop runner and biner was used to hitch the butt back to the other end of the lowering line (going back to porty). So as it was lowerred, the butt slid down the line towards the porty and into the backyard. The pic has pretty much the whole scene including the remainder of the leaner. Worked beautifully. One ground man to get it to where it is in the pic.
I AM sure I wasn't the first person to think of this, and think I remember hearing something like this online.. Anybody ever use this or remember hearing about it?
 
I've used that one a few times on a much smaller scale. It works much better when used with another line just as the zip line. Its good to take short cuts where you can.
 
IN this case the piece needed to get turned 90* to fit in the yard. So it seems like it is easier to turn it by placing the the tip tie and the but tie as close as possible to the balance point. The further out they are the more you gotta fight to turn it.
Ya that was fun... trying something new and it working so well.... made my day and is definitely going in the ISA presentation in Pittsburg... August 10th if you can make it.
 
Pretty Slick!

i call SpeedLining GravityBending in my mental cartoons; Porty (Guess i still have the ol'original Poor T, that works great!) is called a RopeBrake generally etc.

Did you know, that if ya send a guy searching for a SkyHook on Monday; he won't budge if ya tell him 5x to get the GravityBender on Thursday? It is a proven statistical fact, from many tests!:D
 
Nice work!

If I were to call your setup a 10 for size, I've only dnoe stuff at about the 3 level on that scale. Same principles but a much lower "Oops Factor"

Isn't it fun to make ropes work, along with gravity, instead of dealing with more laborers?

Tom
 
Good job.
In the first picture the ladder is standing, in the second it's on the ground, did you knock it over? :eek:
It brave of you to do work like that and leave the ladder up, the law which is your namesake (Murphy's Law), tells me to always get the ladder out of harm's way when working.

One time I used a ladder to climb a tree out in the woods. Once I got up there my view to the ground was obscured and I forgot the ladder was below. The first piece I bombed out was about a thousand pounds.
I don't know the exact force a 1000 pound log falling 30 feet generates, but I now know it exceeds the load capacity of an aluminum extension ladder.
 
Nice Job!
One factor I have noticed is the speed line seems to flex alot so I am buying a 7/16" 300' static line (Endura braid from New England from Charli Porttorff) This way I will eliminate the bounce factor. I guess you did'nt need a controlled decent? or is the main lowering line used for guiding it down as well as holding the tip up?
It may be lazy but more and more I am trying to set the speed line ends in some type of retrievable fashion. What I mean is on the upper half of the speedline I'll try to run it through a crotch and then down to the ground. That way I dont have to climb back up and disconnect the rigging.
Also I like to be able to adjust the length of the attachment point of the butt end strap. I've used a fiddle block, a pulley and a prussik or the strap method you used.
Charli Porttorff is working on a double pulley system to reduce the bend on the speed line. Two pulleys in tandem to hold the butt end up. Petzl makes a double pulley but that is for small work. He mentioned two 4" stainless steel CMI pulleys attached together. Maybe we will see this product in the future...

Your pic. is a great example of truly fine rigging. I bet this type of rigging is way over the head of alot of tree services out there...
Frans
 
Running the top end of the line through a crotch and tieing off at the base of the tree amplifies the load on the spar. If you wanted to make that end retrievable you could tie a running bowline or other suitable termination. Then, attach a retrieval line to the running loop.

Tom
 
Tom, I've been called dense, as well as stubborn, and several other choice names, but can you explain how running the line to the base would increase the load on the spar? I just don't see that. :confused:
 
The bend and loaded position after on the spar/anchor is different than running straight to spar and stopping without bend as a pattern in all cases with the line force.

The speed line loads higher and bends for it is carrying load in leveraged direction of pull to the line's axis of support. Reducing the elasticity/forgiveness keeps line/load higher for more clearance as it doesn't give in to these forces; but sending any dynamic shocks to line, as line doesn't give; screeeching high forces; for the power to stay up must come from someplace; and not having an elastic line will load anchors more by hgiher tension, carrying same load at higher leveraged angle of line bend; and at the dynamic shock moments, that is multiplied much higher by the lack of elasticity, and the raw power coming thru to pull on anchors.

Or something like that.
:alien:
 
Originally posted by Tom Dunlap
Running the top end of the line through a crotch and tieing off at the base of the tree amplifies the load on the spar.Tom

I won't argue this point other than to say I don't think it does amplify the load. (don't get spyder started)
But if the end is tied to another tree, in a location in line with the direction of the speed line, it could eliminate the need for a guy rope because it puts the load in an up and down direction on the tree, instead of pulling to the side, which is dangerous.
 
Frans,
l
Talk to me if you want a cheaper speed line....the prices I get an unmatchable. I'd guess my DS Composite, at 7/16, would cost 60-75 cents per foot. Minimum tensile is 9900 lb, stretch is 2- at 40% load.
http://www.psrope.com/psrope/catalogpdf/DSCompositeDoubleBraidRev8.pdf

I have 250 feet of the 9/16, which is awesome on the GRCS...and, while heavy, would work fine for speedlining.


Murph, great idea...to save ground help, and rigging gear and time. likely that method didn't allow much fleiblility to lower independantly of tensioning the speed section of the line, but it obviously didnt matter, as it came out slicker than snot on a whistle.
 
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As 2 observed machines, a pull to a top of spar etc.; would logically be differnet than a pull to top, bend, and later pull (except at balance point 120degree bend)

The leveraged power found in the way of the bent line; exerts higher leverage against the line tension(less against bend from 120-180deg.; while the leverage is more powerful agianst bend(less agianst line tension) from 0 (a 2/1) to 120 degrees. So, depending on what the bend is at, and what you are truying to achieve, or prevent; shows which end of the rope lever you would want to use; not to wear your self out, on the 'wrong end'. The 120 degree bend is just where on the scale the point of balance is between line tension and 'bend tension'.

Guess, i shouldn't mention the rotational direction of the given force applied in this fashion.... :angel:

Elasticity lost from system will force more undampened, immense-immense forces on line's static componenet (tensile) to transfer to supports, compounded by leveraged angle of the force applied to the line's long axis of support.

Okay Mike, i'll be good (er mebbe jest a lil better?)
:alien:
 
maybe I can help make this a little easy ,If you use SRT try it both ways and watch and feel the difference in how your wieght is applied to the tree .This is basically the samething but at a much lower scale.Mike if you were rigging a tree to be removed using natural crotch rigging how many crotches would you use ?
 
hey I dont mean to be rude but is it not pretty basic knowledge to not overload your rigging system?
Are we going over and over the same ground here?
Frans
 


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