TreeStuff.com Accelerated Rope Wear Testing

[bonner1040]

In an effort to better understand cycles to failure and its effect on climbing and rigging lines used for arborist work, TreeStuff is doing a long term experiment.

The Data:
https://docs.google.com/spreadsheets/d/1xKvJXYmYLfNI8x6Fchs0T_dHBk7IL39Bm4jmfUpZo2Q/pubhtml

The Test:
-100,000 cycles at 110lbs
-Each cycle raises and lowers the weight 6"
-The rope is running over a 3/4" arborist rigging block at 90 degrees
-We will test and publish the breaking strength and strength loss of each rope

We will be posting results of this ongoing test as often as possible, and the above link will continually update. Our plans are to test a wide sample of climbing and rigging lines available to the modern arborist.

<iframe width="640" height="360" src="https://www.youtube.com/embed/ybJ2muqeWLg" frameborder="0" allowfullscreen></iframe>

 

[woodslinger]

That sounds like some very useful data to have available.

 

[MasterBlaster]

VERY useful!

 

[Mick!]

Why don't you do it with nicked and damaged rope instead of new stuff? Or testing the effect of knots on rope strength? or even better get a definitive answer to how big a percentage of the weight a half hitch takes in front of an end holding knot.

 

[treebilly]

VERY useful indeed.

 

[MasterBlaster]

do it with nicked and damaged rope

I bet a nickle they do.

 

[Mick!]

Then do that, we all know undamaged climbing rope will hold ten climbers, where's the news there?
You can pull start a truck with another on decades old frayed three strand.
Show us the loss of using glazed rigging line frinstance.

 

[pantheraba]

How do you quantify degree of glaze or wear?

 

[Mick!]

I'll post a pic of mine tomorrow.

 

[Grendel]

I dig it. Will you up the weight for the larger diameter lines?

I like the cycles to failure aspect of this one. Break testing knots and damages lines would be cool too, but it would be hard to quantify the results, maybe not so much with knots. . . anyways. Keep us updated!

Cheers

 

[Sgriff]

Knot tests have been performed,there is alot of data on that,cycles to failure is intriguing. I don't see a benefit for a "knick my rope till failure",or even a "overlaoded the shit out of my rope while rigging and its glazed to hell failure" but I will get some popcorn out for any of the above!!

 

[MasterBlaster]

Sit next to me!

 

[Pelorus]

Good stuff, Nick.
It would take a lot to sway me to abandon my two favorites for climbing (Yale 11.7mm) and rigging (Samson Arbormaster).

 

[flushcut]

Interesting.

 

[bonner1040]

New results posted.

 

[Reddog]

Cool stuff!

 

[SouthSoundTree-]

Why the high number of cycles? Arbitrary? Some ball park figure based on x,y, and z?

 

[flushcut]

Samson for the win!

 

[Limbrat]

Very interesting Nick. I'm curious as to what caused the black mark on both ropes. Was it caused by heat, a deposit from the sheave of the block or something else? I imagine the block got very hot in the process too. Thanks to you guys for taking the time (and money) to put the Stuff that keeps us alive to the test.

 

[pantheraba]

Yeah...what the Rat (Ray) said...appreciate you guys.

 

[DMc]

.... I'm curious as to what caused the black mark on both ropes....

I would think that 100,000 cycles over a piece of aluminum, by it self, would leave a black mark.

I think you have setup a good test Nick. Would it be possible to make a setup that would replicate rope and webbing bridge cycles to failure?

 

[bonner1040]

Yeah. i can definitely do that.

posted new results. Follow the link in the OP

 

[Climbhigh]

Hows that CMI pulley holding up ? it would be interesting to see a picture of the rope before the break test just to compare abrasion differences.

 

[Sgriff]

^ 👍

 

[Climbhigh]

Knot strength testing ; http://www.neropes.com/Resources/sail_reprint.pdf