Does testing rope strength weaken it?

Woodwork

Well-Known Member
Location
Tidewater
Hey, all,
I have some 1/2" 100% polyester rope (Yale XTC Fire) I would like to test to say 1000 or 1500# to make sure it's still safe to use as a top rope on roof job I'm on. If I put it on a load cell to 1500# (or picked up a 1500# object with it), would that weaken it thereafter because I strained the rope with that load?
Is a visual inspection enough to pass/nopass it?
It's supposedly 6200# break strength new, but rope is getting old and has seen some sun.
Thanks,
Jeff
 
Last edited:

Brocky

Well-Known Member
Location
Michigan
UV damage should be easy to see, twist the strand apart and compare the outside to the inside, a picture would help.
 

Woodwork

Well-Known Member
Location
Tidewater
Thanks, fellas. I'll post a pic of some of the "worst" parts of it later.

ETA: Here's some of the "worst of the worst" in the rope (nearly all of it is in better shape than this):



I don't need the rope to have its original strength; I keep the slack out of my top rope, but if I didn't, I estimate the absolute worst I could fall would be 10' x 160# for 1600 ft-lb (and honestly I don't know whether my roof anchors would even take a 1600# shock load...and I suspect my prusik loop would slip long before that) ... I know "new rope" is the right answer, but would really rather not buy another rope right now that'll just get eat up on the roof at the rate this job is going...and it's only me on the rope, no innocent bystanders...

Also, despite the title of the thread, this isn't really for fall-arrest -- just work positioning and keeping me on the roof, since I tend slack pretty faithfully..
 
Last edited:

Woodwork

Well-Known Member
Location
Tidewater
Thanks, guys.

I should add that I'm not trying to get anybody to say "Sure, it's fine!" -- and can't really expect more than a seat of the pants guess -- just trying to get a feel for whether people who are far more experienced than me at using ropes would use this rope for the purposes I've described. (I'm not an arborist, though I do have gear and have climbed trees.)

If I lift 1500# once with it, it's not unreasonable to expect it to take 1500# again, is it?
 
Last edited:

Crimsonking

Well-Known Member
Not trying to get anybody to say "Sure, it's fine!" -- and can't really expect more than a seat of the pants guess -- just trying to get a feel for whether people who are far more experienced than me would use this rope for the purposes I've described. (I'm not an arborist, though I do have gear and have climbed trees.)

If I lift 1500# once with it, it's not unreasonable to expect it to take 1500# again, is it?
I think the responses you got were good advice. You’re trying really hard to justify it. If you heard the logic you just used in any safety scenario, would you not balk at it? This is a safety scenario, so please don’t use the “if it works once, it should work again” thought process. Instead, as others have said- if it’s on your mind this much, and you’re trying this hard to justify it, you should just get a new rope. I’ve written reports on incidents that were traced back to justification based on external and internal pressures. Please don’t risk being in my next report. I hate doing them. The only good that comes is hopefully preventing future occurrences. Be a fruit of these reports, not a vegetable.
 

Woodwork

Well-Known Member
Location
Tidewater
OK, thanks, I appreciate the advice and patience.

Just ordered some more 1/2" Yale XTC, this time in white/yellow. I like the way that XTC Fire handled.
 
Last edited:

Reach

Well-Known Member
Location
Atglen, PA
Don Blair wrote about this inArborist Equipment. The book is on the short list of required reading. Does anyone even read books anymore? We should!
I have not read that book yet, and for that matter I’m not sure I’ve heard of it. I will have to look now!

Edit: I just looked it up, $350+, wow! That’s a little out of my current price range.
 

Tom Dunlap

Here from the beginning
Administrator
Wow!

I didn’t realize that my purchase of textbooks would become financial investments!

makes me wonder what mine might be worth. It’s one of the 100 Authors Release. Numbered, signed and with a personal note from Don

it’s been published as a paperback from ISA
 

Reach

Well-Known Member
Location
Atglen, PA
Wow!

I didn’t realize that my purchase of textbooks would become financial investments!

makes me wonder what mine might be worth. It’s one of the 100 Authors Release. Numbered, signed and with a personal note from Don

it’s been published as a paperback from ISA
Does that mean my old Calculus textbook is going to be worth something some day? Unfortunately, I doubt it...

With all that going on, it surely must have some value!
 

JeffGu

Well-Known Member
Also, despite the title of the thread, this isn't really for fall-arrest -- just work positioning and keeping me on the roof, since I tend slack pretty faithfully..

This is common for pitched roof work, since simply having the rope to maintain balance is usually all that you need to walk anything under 10/12 pitch, and your aim is to not go off the edge of the roof. That rope will stop you from doing that as long as you keep slack out of it. Without a fall arrest device, going over the edge is simply not an option... you need to pay attention to rope angle, slack and length to prevent that. Only the shock load of dropping over the edge can generate enough forces to break the rope, even in its current condition. The constant abrasion of the roofing materials will fuzz them up quickly, just keep an eye out for cut strands and don't leave it up on the roof. The UV is hell on ropes.

You could always cut a few feet off of the rope and have it break tested for about $25 if you're worried about it. I'll go ahead and bet that it breaks well over 4500 lbs. and quite probably over 5000 lbs. even if your piece of the rope includes the parts shown in your pics.
 

evo

Well-Known Member
Location
My Island, WA
I have not read that book yet, and for that matter I’m not sure I’ve heard of it. I will have to look now!

Edit: I just looked it up, $350+, wow! That’s a little out of my current price range.
You can have mine for $375... there is a second edition in print which should be much cheaper?
 

New threads New posts

Kask Stihl NORTHEASTERN Arborists Wesspur TreeStuff.com Kask Teufelberger Westminster X-Rigging Teufelberger Tracked Lifts Climbing Innovations
Top Bottom