friction savers

[bruce6670]

Can anyone help with a question about friction savers ?
I was wondering if running your climbing line through such small rings creates to tight of a bend.Just seems to look like damage could occur even though it's only carrying your body weight.
Any help would be appreciated. Thanks.

 

[treemandan]

Can anyone help with a question about friction savers ?
I was wondering if running your climbing line through such small rings creates to tight of a bend.Just seems to look like damage could occur even though it's only carrying your body weight.
Any help would be appreciated. Thanks.

No its fine, very nice.

 

[Ax-man]

I noticed you said small rings. Which could also mean thin. The earliest versons of the ring ring friction savers did have thin rings compared to the later versions that came along.

If you are climbing on one of those older versions then the answer your question is yes the bend ratio is not acceptable. If your using a FS with the bigger rings then your OK to go. Buckingham's friction saver with the steel rings is the best to me although others will surely disagree. Buckingham's steel rings are bigger on the inside diameter and thicker on the outside diameter than the other ones on the market. You can buy rings anywhere but Buc rings are only available through Buckingham and they do not sell them seperate. You have to buy the complete friction saver.

Larry

 

[SINGLE-JACK]

Can anyone help with a question about friction savers ?
I was wondering if running your climbing line through such small rings creates to tight of a bend.Just seems to look like damage could occur even though it's only carrying your body weight.
Any help would be appreciated. Thanks.

Any bend, over approx. 10 degrees, will reduce the load capacity of rope. The diameter of the bend relative to the diameter of the rope is the "bend ratio". There has been testing and debate to determine that 4:1 is often cited as the minimum recommended ratio for continuous use. However, even that recommendation is at the cost of a reduction in load capacity of 15%. Even 8:1 will reduce capacity by 5%.

The modern friction saver has rings that are approximately the diameter of the most common arborist rope. This results in a bend ratio of 1:1 which is vitrually the same bend ratio bend caused by most knots. It is often cited that knots can reduce load capacity by 50%. So, it's fair to assume that the load capacity of a rope through a modern friction saver should be expected to be approximately half the rated capacity of the rope.

ANSI Z133.1 standards for arborist climbing lines:
Arborist climbing lines shall have a minimum diameter of 1/2" (12.5mm) and be constructed of a synthetic fiber, with a minimum nominal breaking strength of 5,400 lbs(24kN) when new. Then, at 50%, due to the bend ratio of the friction saver, the capacity is reduced to 2700 lbs. With a 1/5 safety factor, the Working Load Limit for a new rope through a new modern friction saver can be expected to be 540 lbs.

So, don't gain any more weight and don't bounce around too much or you're a gonner.

 

[canopyboy]

I like what singlejack said. To summarize though, you're not reducing the strength of your rope where it passes over the friction saver any more than the spots where you have it clipped to you harness or have tied a knot.

This and dynamic loading are two of the biggest reasons we use climbing lines rated for more than 20x our actual weight IMO.

 

[Treetom]

Bruce 6670, I've had good luck with the leather type cambium/friction saver, when I use one at all. I usually just wait till the 'ol True Blue gets worn enough, then replace it. Replacement is never from wear because of rough tree crotches, usually a saw nick or some other abuse. I've shyed away from the ring type friction saver: I just don't like the tight bend it puts in the climbing line. (Wasn't there also a recent post on one of these rings failing?) I've seen some climbers hang a pulley for use as a friction saver. If there's an effective way to set a Hobbs block from the ground, it may be the way to go. Just some thoughts.

 

[SINGLE-JACK]

Bruce 6670, I've had good luck with the leather type cambium/friction saver, when I use one at all. I usually just wait till the 'ol True Blue gets worn enough, then replace it. Replacement is never from wear because of rough tree crotches, usually a saw nick or some other abuse. I've shyed away from the ring type friction saver: I just don't like the tight bend it puts in the climbing line. (Wasn't there also a recent post on one of these rings failing?) I've seen some climbers hang a pulley for use as a friction saver. If there's an effective way to set a Hobbs block from the ground, it may be the way to go. Just some thoughts.

Yeah, the leather ones are pretty good. I carry one topside if I need to double crotch because they're small and light. But, I love the Buckingham Friction Saver with steel rings.

There was a recent incident(s) about broken rings. However, they were 'off-brand' unrated alluminum rings and recalled. You can read the thread:
http://www.arboristsite.com/showthread.php?t=105575&highlight=recall+rings

There are ways to rig pulleys from the ground: adjustable false crotch, krab-strap-pulley, just to name two. A Hobbs block is a bit overkill (not punny). It is rated at 80,000 lbs. Can't be that worried.

And, If you like the leather one you'll love the DAN HOUSE ROPE SLEEVE. http://www.newtribe.com/catalog/product_info.php?products_id=281

So many choices - so little money - Cool times we live in - eh?.

 

[Treetom]

Informative response, Single-Jack.

 

[bruce6670]

Thanks for the help everyone.I now have more things to consider but will definately make a more informed decision with this information.
Thanks again.

 

[TreeW?rx]

And, If you like the leather one you'll love the DAN HOUSE ROPE SLEEVE. http://www.newtribe.com/catalog/product_info.php?products_id=281

I have used the above mentioned cambium saver and really liked it. I made one of my own using 3/4 inch electrical cable armor, aka BX. If you use the water tight (plastic coated) and come up with something to keep the end of it from slicing your rope, (it is made out of metal) like electrical tape with a wire gromet, you can make your own for about $4.

 

[SINGLE-JACK]

...
I made one of my own using 3/4 inch electrical cable armor, aka BX.
...

You've actually made one out of BX?
I'd really be interested to see that!
Would you post a picture, please?

This is what I know as BX:

 

[bruce6670]

You've actually made one out of BX?
I'd really be interested to see that!
Would you post a picture, please?

This is what I know as BX:

I think he means Greenfield flexible conduit.

Either way, I don't think I would use it.

 

[canopyboy]

I made my own out of that stuff as well. You need the watertight BX for the rubber outside, otherwise it doesn't stay put very well. You need the metal inside for the rope to slide easily on. The key is the little caps you put over the ends or your rope won't last long enough to use it twice. Finding the right caps isn't easy, but doable.

I can try to take a picture tonight and post, but they look just like the one in the link from Treewurx. And I find I use them more often than my ring types, way faster to set and actually seem to be less friction.

 

[SINGLE-JACK]

I made my own out of that stuff as well. You need the watertight BX for the rubber outside, otherwise it doesn't stay put very well. You need the metal inside for the rope to slide easily on. The key is the little caps you put over the ends or your rope won't last long enough to use it twice. Finding the right caps isn't easy, but doable.

I can try to take a picture tonight and post, but they look just like the one in the link from Treewurx. And I find I use them more often than my ring types, way faster to set and actually seem to be less friction.

Yeah, I'm familiar with the DAN HOUSE ROPE SLEEVE. I think Treewurx copied the link I posted earlier in this thread (below) - which is fine. It was the term "BX" that threw me. I think the Dan house Rope Sleeve is made from a very flexible liquidtight conduit with special end caps - a very different thing than BX.

I understand they are great. But, I've been a bit nervous about my lifeline rubbing inside a thin a metallic sleeve. Apparently, you're ok with that and it's not really an issue. I've seen them used in Moss' videos. I would very much like to see pix of what you made. More importantly, I'd like to know more about how they wear out.

...

And, If you like the leather one you'll love the DAN HOUSE ROPE SLEEVE. http://www.newtribe.com/catalog/product_info.php?products_id=281

...

And, If you like the leather one you'll love the DAN HOUSE ROPE SLEEVE. http://www.newtribe.com/catalog/product_info.php?products_id=281
I have used the above mentioned cambium saver and really liked it. I made one of my own using 3/4 inch electrical cable armor, aka BX. If you use the water tight (plastic coated) and come up with something to keep the end of it from slicing your rope, (it is made out of metal) like electrical tape with a wire gromet, you can make your own for about $4.

 

[moss]

... understand they are great. But, I've been a bit nervous about my lifeline rubbing inside a thin a metallic sleeve. Apparently, you're ok with that and it's not really an issue. I've seen them used in Moss' videos.

Not to worry, I've beat the crap out of my liquid-tight conduit sleeves and they won't hurt your lifeline. What happens first is the vinyl cover starts to wear off, at that point you retire it. If you insist on continuing to climb on it after the vinyl cover falls apart the inter-locked steel lining starts to come apart, even then it does zero damage to the rope, I know because I've climbed on separated conduit sleeves (not intentionally, was pushing it). Unfortunately I've wiped out the vinyl covering on the New Tribe sleeves in one climb, apparently I'm rough on them. That particular spec conduit is not really suitable for daily work climbing IMHO. New Tribe guarantees replacement on failure so there is some back-up.

This spec conduit is more durable and is what I use, I'm hoping New Tribe will switch to it:
http://www.mcmaster.com/#8069k13/=42oj1m

This is the endcap you need to use:
http://www.tnb.com/ps/fulltilt/index.cgi?part=5333

It's called a "ground cone" and it's inside the part above.. I've tried buying just the ground cone but the minimum order is 200 pieces.

Also... Go with the 3/4" trade diameter, not the 1/2". An 11mm rope will run though the 1/2" trade diameter conduit but there's too much friction especially in the winter, when it's cold out you won't be able to keep the 1/2" sleeve on a branch.

Otherwise they're very easy to install and take out of a crotch remotely, same as a leather sleeve but less friction to climb on.
-moss

 

[pdqdl]

help a converting "old schooler" out

I have never used a rope saver sleeve, nor have I ever seen it done. It seems simple and easy, but why go to the trouble?

I figure there are three reasons to use a sleeve:
1. It reduces climbing friction.
2. It reduces rope wear.
3. It protects the tree.

It seems to me that it would slightly increase the risk of not getting the rig out of the tree, too.

Which are the reasons that you use them for?

 

[zopi]

Asked the question the other day about who uses blocks at the climbers TIP, then did some research..(ok, i dowloaded the torrent of the tree climbers guide)

It states that ideally the turn ratio should be 4:1..a 2" radius in 1/2" rope...probably not essential, but minimizes wear....

 

[Blakesmaster]

I have never used a rope saver sleeve, nor have I ever seen it done. It seems simple and easy, but why go to the trouble?

I figure there are three reasons to use a sleeve:
1. It reduces climbing friction.
2. It reduces rope wear.
3. It protects the tree.

It seems to me that it would slightly increase the risk of not getting the rig out of the tree, too.

Which are the reasons that you use them for?

Climbing friction is my main reason, much easier to swing 'n slide with less friction. I also like them on prune jobs where the tree has especially soft bark but I'm not the type of guy that uses one every time, no matter what. If it's to my advantage ( i.e same TIP for an extended climb ) I'm all over it but you won't see me take the time out of my day to set one up for a quick rappel.

 

[SINGLE-JACK]

Asked the question the other day about who uses blocks at the climbers TIP, then did some research..(ok, i dowloaded the torrent of the tree climbers guide)

It states that ideally the turn ratio should be 4:1..a 2" radius in 1/2" rope...probably not essential, but minimizes wear....

It's not so much wear but strength loss due to bending. Any bend, over approx. 10 degrees, will reduce the load capacity of rope. The diameter of the bend relative to the diameter of the rope is the "bend ratio". There has been testing and debate to determine that 4:1 is often cited as the minimum recommended ratio for continuous use. However, even that recommendation is at the cost of a reduction in load capacity of 15%.

The outer fibers in a rope are stressed more hightly when formed around a pulley. The following data if from On Rope (Smith & Padgett) - the data was compiled by Donald F. Blair of Sierra Moreno Merchantile Co. and Richard Hildebrand of Yale Cordage:

2:1 = 30% reduction in rated rope strength
3:1 = 20%
4:1 = 15%
5:1 = 12%
6:1 = 10%
8:1 = 5%

 

[TreeW?rx]

I will snap some pics of the ones that I made. They took about 15 minutes each to make. The cost to make 4 of them was about $20ish. They pull in an out just like a leather one. The nice thing is that you can make then as long as you want. I climb some pretty big cottonwoods and the crotches far up in the tree can be pretty large. I use them every time I climb. the cottonwood and elm that I spend the most time in is very rough barked and will tear up a line quickly. I figure if I go through $20 worth of friction savers and make my several hundred dollar climbing line last longer it is money well spent.