question about shock loading a rope and blocking

there is no way to accurately guess how far a rope will stretch every time with any given weight. that being said it is dangerous to have stretch in critical rigging applications. what if you had to chunk down a large spar and it was up next to a roof. what if you can only let it drop 3 feet because of the close proximity to the roof and the house.

i for one would most certainly not want to use a rubber band like true blue or arborplex. i would most likely use doublebraid which has enough energy absorption to arrest the falling piece but not in excess to cause the rope to stretch soo much that it causes roof damage.

wish i could use the force like yoda to lift pieces up and down.
applaudit.gif
id revolutionize the tree industry.
we wouldent even need chainsaws, we could just use our light sabers but im not sure how the cambium would handle the heat.
 
I've used both True blue and Stable braid and with the right ropeman i couldn't tell the difference. I will chose how much I take by strength in stem and who's roping. Another climber that worked on the other crew would break lowering points all the time using true blue with the awesome stretch factor. Granted he wasn't the most careful climber but there is no replacement for a skilled ropeman no matter what rope you choose to run.
 
That's just logical to a newbie, But the reality of this work is that the hypothetical situation you made up is one in a thousand. It just doesn't happen that often. And when it does, you can either pretension the line to take the stretch out, switch to a static line, or find another way to get the job done..

Maybe its depends more on the topography around the trees in your market. I seem to have more room to work than many other areas. So by all means keep some static line around for those scenarios. AND use the dynamic line in your day to day rigging work. It can save your life, or make your work so much more productive.

You talk about cutting 3-4' pieces... We take stuff much bigger all the time.. Its no big deal...

The mentality of not wanting stretch in the line is coming from a newbie's perspective. Some people can stay in this business 20-30+ years and not change much.. People get attached to the way they were taught by "marv", and stick with it, ferrociously...

Realistiucally, how often do you find yourself rigging over rooves etc?

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there is no way to accurately guess how far a rope will stretch every time with any given weight. that being said it is dangerous to have stretch in critical rigging applications. what if you had to chunk down a large spar and it was up next to a roof. what if you can only let it drop 3 feet because of the close proximity to the roof and the house.

i for one would most certainly not want to use a rubber band like true blue or arborplex. i would most likely use doublebraid which has enough energy absorption to arrest the falling piece but not in excess to cause the rope to stretch soo much that it causes roof damage.


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Realistiucally, how often do you find yourself rigging over rooves etc?

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Every week, sometimes every day... you mean you don't?

What kinda tree work do you do? Without houses and gardens and fences to work around... rigging just ain't all that complicated is it?.
 
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That's Daniel dude, that's how he rolls. He is the classic example of a little bit of knowledge is a dangerous thing.



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yes, that sums it up. Please don't listen to him.

And, from past postings, any bad-mouthing toward Daniel is justified. He has asked for it over and over and over again.

If you are a new reader and wonder why Daniel gets crap, it's because he truly deserves it, no lie.

Also, Daniel, for big rigging I use what you call static line, (even though it is NOT), and I'm sure I rig down heavier stuff than you do and do it with finesse. I have never broken a rope on one of my jobs, EVER.

It's the skill of the groundman and the equipment used in the system (meaning blocks and good lowering devices). I feel I'm part of it, because I am the one that helped the groundman develope his/her skill and give them direction on what is needed.

Blinky, you have said a lot of good things. Tom too.

I'm just glad it is you guys, because I doubt I could keep my cool as good as you.




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The whole anti-double braid thing is weird... talk about dogmatically sticking to something you were taught BITD.

It has to be based on natural crotch rigging because there is NO reason why a 12-strand or a 3-strand would out perform a double braid using blocks... and I don't know anybody who chunks trunk wood on a natural crotch... you could leave stubs on the way up I suppose.
 
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I couldn't disagree more with both of you...

Big Jon tore me me a new one, one time when he showed up to rig out a monster oak over a house and all I had was double braid. He wouldn't rig the tree with that and acted Like I was trying to get him killed by asking him to rig with double braid.

Once he got a more dynamic line in hand (hi-V), he proseeded to lower out 40' red oak leads, tied perfectly at their balance points. So well balanced that you could move them with one finger. It was a beautiful thing.. Guy M was actually on site for a few minutes..



enough said... I gotta go!


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This big jon guy was rigging out 40' red oak leads on a 1/2" line and your trying to tell me he's an amazing rigger?
 
I've seen willow oak go 40' on an 8" collar so, benefit of the doubt, ~1200# to 1400# with branching and no foliage.

Instinct eh, Daniel? Sounds like your doublebraidaphobic super rigger was busting WLL by a factor of 2 and doing it over and over. Totally possible, totally believable... but how do you guys know when that rope can't be pushed anymore? Why not use EVERY advantage and use a rope suitable for the task? Hmmm?
 
here in hawaii there is lots of targets. alot of people here have beautifully manicured lawns and gardens. even when it's just grass i still rig it down because i was a landscaper before i did this job and i know how much time it takes to make grass recover. falling pieces of wood leave holes in the yard which need to be filled and re seeded. it's alot of extra work that is not needed at the end of a hard day. one of the ways i sell my work over the competition is i leave little impact on the surroundings. grass, shurbs, smaller tree's, plants and landscape materials all stay un touched. my clean up is soo good the only thing you see after a removal is a stump that sits only 2-3inches above the ground. so the point is everyday is full of targets and i rig about 80% of the time unless it is in a location where it is logical to just chop and drop like in a forested area or dirt lot.
 
I too will often lower pieces just to keep the lawns from getting damaged. That depends on the customers relationship with his lawn, (determined in a conversation before that is factored into the bid). Or to move the work to a favorable LZ, or to save time cleaning up a million little broken sticks..

What I meant is how often do you face the situation described by Josh, that is you are worried that the stretch in the line is going to allow more fall and damage a roof or whatever... Maybe that should be taken one step farther and qualified by saying how often do you face rigging scenarios where you can't pretension the line enough to take the stretch out, so you have to be concermed about the piece dropping too far due to stretch in the line?

The answer for me is NOT TOO OFTEN.. I know how to sweat a line in and I have a GRCS. I don't need a static line.
 
Once again I have to explain it to you Chip... How thick are you that you can't understand the concept?

Yes I AM OK with working within a 15-20% ABS load limit, providing shock loads are controlled and vector forces are directed to ensure the tree will not fail... I do it all the time. 10% is an arbitrary figure. When a person does not understand how to control shock and manage vectors, then he better stick to 10%. I AM quite comfortable exceeding 10% in low risk situations..

THIS IS THE POINT:
Its not the rope you need to worry about.. ITS THE TREE. That is what Jamie was so politely trying to tell you. RE-READ his post. Watch the video. Stretch in the line will greatly reduce the load put on the tree. THAT is true, no matter how well the groundie runs the lines. No matter how good he is, the stretch in the line is going to dramatically reduce shock loads, allowing heavier peices to be safely rigged.

If a rope breaks I AM going home for dinner and maybe the only damage done is to the lawn, or some inexpensive shrub, or service line. Obviously the greater the value of the potential obstacles, the less tolerance there is going to be for taking bigger pieces. So I AM really not all that concerned about the rope breaking becasue there is such a small probablility that it will break, and even if it does, the consequences are minimal. HOWEVER, if the tree breaks that could kill or injure the climber.

SO the real concern with taking heavy pieces is making sure you don't overloading the tree..

Take a 500-800 lb limb and add a little shock loading and you have a very dangerous situation.. If you control the shock load.. and you set the riggin up right its no problem.. Given all other factors are constants, such as the rigging block, and skill of th ground man etc, the best way to control shock loads is to use a dynamic rigging line.

Its going to put a lot less stress on the tree to use a line with a lower ABS and more stretch.. That was the point of the Yale video.. How F'in stupid are you people that you can't get that concept.. Its frustrating that I have to keep saying the same thing over and over and keep getting insulted by a bunch of clueless idiots...

Chisholm's abscence around here is HUGE! For some reason you all can't hear it from me, no matter how I try to explain it. Two sentences from him and you all would shut right up..

Big Jon sent me an email after the white oak riggin video, congratulating me for the rigging and telling me to stop trying to teach this stuff. Guess he's right again. it doesn't do any good! Where is the beating your head against the wall icon anyway?



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I've seen willow oak go 40' on an 8" collar so, benefit of the doubt, ~1200# to 1400# with branching and no foliage.

Instinct eh, Daniel? Sounds like your doublebraidaphobic super rigger was busting WLL by a factor of 2 and doing it over and over. Totally possible, totally believable... but how do you guys know when that rope can't be pushed anymore? Why not use EVERY advantage and use a rope suitable for the task? Hmmm?

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