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AaronB

Diameter of Prusik when used with 8.1 mm rope?

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Sorry, I tried to search as I know this must have come up a million times before, but couldn't find anything.

 

I'm wondering what diameter prusik, people would use with 8mm rope. The ones I am currently using slip way too much, even with many loops.

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A Tibloc isn't the answer to my question. I need something that will be on the rope so I can transfer the weight of my partner to an anchor. Its hard to light up, when you have to stay in self arrest while your partner crawls out of crevasses. Especially when you don't have a lighter, and are using matchheads against your zipper. wink.gif

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I prefer a Tibloc too, but to answer your question 6mm should work, 5 for sure. Anything larger will slip and anything too much smaller could tighen up to much. wave.gif

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Use a rule of thumb for prusik cord: 60% - 80% of the host rope. So for 8mm rope, 5 works great & 6 will work but you may want an extra wrap with the 6mm.

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5mm works great. 6 and up is a little bit fiddly, 4 works very well I just can't bring myself to prussic out on it.

 

I use part of my texas rig to tie to an anchor initially so that I can get out of arrest position. In this use I would stay with the 5. If all you are doing is preplacing something to transfer with 4 would hold just as well, you'd just have to fiddle a bit to get it released after the transfer.

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Prussik might work just as well as a Tibloc in a tie-off situation. However, in my experience, Tiblocs work better than prussik knots when you're climbing out. When climbing up a snowy crevasse wall the prussiks tend to ice up and you have to untie and retie everytime you want to move the knot up.

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Use a rule of thumb for prusik cord: 60% - 80% of the host rope. So for 8mm rope, 5 works great & 6 will work but you may want an extra wrap with the 6mm.

 

This is the answer. According to Rigging For Rescue of Ouray, CO, the ratio of prusik cord diameter to host rope diameter is 2/3 to 3/4.

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Use a rule of thumb for prusik cord: 60% - 80% of the host rope. So for 8mm rope, 5 works great & 6 will work but you may want an extra wrap with the 6mm.

 

 

This is the answer. According to Rigging For Rescue of Ouray, CO, the ratio of prusik cord diameter to host rope diameter is 2/3 to 3/4.

 

Mike must have changed the numbers when he bought the company from Kirk. Gotta do something to be different - Typical tongue.gif

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cry.gifPractical Limitations: In practice, this knot would be almost impossible to tie under load; shortening one end and resecuring the line would be preferable. As a knot , it cannot pass through blocks or sheaves. In the critical environments presented by climbing, search and rescue, and boating, there are no applications where the Sheepshank would offer a preferred solution cry.gif

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in my 37 years of climbing, i still have absolutely no idea how to tie a bowline or have ever wish i knew how to tie one

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Yeah, you've shanked some sheep, haven't you Mike?

 

What about a Bachman knot, better than a kleimheist or a Prussik and it works in both directions.

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in my 37 years of climbing, i still have absolutely no idea how to tie a bowline or have ever wish i knew how to tie one

 

mike was climbing in those pre-fetal years.

 

ascent out the birth canal 5.10d R/X ??

 

Bowline is fast and handy guys.

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i was thinking up jugging up prusik peak. does anybody know it's diameter so I can find a suitable cord size to wrap around it?

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...Bowline is fast and handy guys.

 

And in a real pinch, can be tied using only one hand.

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Mike must have changed the numbers when he bought the company from Kirk. Gotta do something to be different - Typical tongue.gif

 

Just came from the class last month. Have no idea when the numbers got changed.

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how about using jumars on a 8mm rope? I know they suggest a minimum diameter but I don't remember. I carried them last year and the question came up, was planning on using them again this year

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I'm not sure what the threshold is (6mm?) but my Jumars hold better on thinner rope than my Tibloc.

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how about using jumars on a 8mm rope? I know they suggest a minimum diameter but I don't remember. I carried them last year and the question came up, was planning on using them again this year

 

Answer => click me

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