adjustable spectra/dyneema/HMPE footloop?

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Re: adjustable spectra/dyneema/HMPE footloop?

Postby PeterFJohnson » Nov 5, 2011 5:11 pm

One can always use a clove hitch(or other suitable knot) to temporarily create a shorter tie in point in their fixed length footloop. This allows a pretty wide range of adjustment for those infeequent times it is needed without having to carry extra gear.
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby Bob Thrun » Nov 5, 2011 5:46 pm

snoboy wrote:What you want build is known as a whoopie sing - a fixed eye on one end (could be permanently attached to ascender if desired) and an adjustable eye onthe other... instructions in this PDF: http://www.samsonrope.com/site_files/12 ... e_2008.pdf

This sounds like what are sometimes called Purcell Prusiks, named after the Purcell Mountains in British Columbia. www.canyoneering.us/docs/purcellprusiks.pdf A whoopie sling is based on a splice in single braid rope. The Purcells use Prusik knots.
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby Caver John » Nov 5, 2011 6:49 pm

If one Insisted on an adjustable footloop but likes the kiss theory a simple prussik would work or the kong slyde whould be a good option. I like the slyde on my long cowstail.

http://i177.photobucket.com/albums/w226 ... 0cf01c.jpg
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby snoboy » Nov 5, 2011 8:02 pm

Bob Thrun wrote:
snoboy wrote:What you want build is known as a whoopie sing

This sounds like what are sometimes called Purcell Prusiks


Similar I guess, and you could use a purcell for a footloop (I do on my just in case prusiks I carry as part of my rope rescue kit} but they are quite different in use, properties and manufacture...
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby LukeM » Nov 7, 2011 9:47 am

Caver John wrote:If one Insisted on an adjustable footloop but likes the kiss theory a simple prussik would work or the kong slyde whould be a good option. I like the slyde on my long cowstail.

http://i177.photobucket.com/albums/w226 ... 0cf01c.jpg


Do you have two separate ropes for 2 footloops? If so, I would say consider just tying a double loop knot at the end of one. Also, it looks like your footloop rope is as thick or thicker than the cowstail rope. To streamline you could go with something much thinner/lighter such as 5 mil spectra.
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby Caver John » Nov 7, 2011 10:31 am

I do have two footloops. This way I can keep both feet in and still push away from a wall or whatever. I also find it easier to footlock with separate footloops. I've been debating goin with a singe strand with double loops though. The footloop cord is something like 6.4mm static cord and the cowstail is 9mm.

Another benefit of using the ropeman on two footloop cords is setting one higher than the other for getting out over lips.
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby LukeM » Nov 7, 2011 11:36 am

Caver John wrote:I do have two footloops. This way I can keep both feet in and still push away from a wall or whatever. I also find it easier to footlock with separate footloops.


That's really interesting and something I'll have to try out sometime. Do you use two feet for most climbing? Also, that cord looked way thicker than 6.4mm! Some kind of optical illusion going on I guess. :)
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby Caver John » Nov 7, 2011 4:24 pm

I do normally use two feet for climbing. Even if I'm only using one footloop, I'll use the left and put my right foot on top of the left, locking the rope in between.
I was wrong about the cord, it's closer to 8mm. Guess I could go with something lighter and cut the bulk down a bit. It's just what I had laying around
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby Jeff Bartlett » Dec 7, 2011 11:41 pm

LukeM wrote:That's really interesting and something I'll have to try out sometime. Do you use two feet for most climbing? Also, that cord looked way thicker than 6.4mm! Some kind of optical illusion going on I guess. :)

This is something I've seen a few times and have been meaning to try for a while myself. Brian Killingbeck from TN, Shane Stacy from AL and Dave McRae from AL all use this approach. I can't imagine it helps with bulk, but it seems like it would definitely save the trouble of switching feet mid-pitch when fending off of a wall, or having to replace your foot in the footloop when reaching a free-hanging section of rope.

I'd be more inclined to try this if I could get my hands on more 5mm spectra... :)
"Although it pains me to say it, in this case Jeff is right. Plan accordingly." --Andy Armstrong
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Re: adjustable spectra/dyneema/HMPE footloop?

Postby LukeM » Dec 8, 2011 10:31 am

Jeff Bartlett wrote:
LukeM wrote:That's really interesting and something I'll have to try out sometime. Do you use two feet for most climbing? Also, that cord looked way thicker than 6.4mm! Some kind of optical illusion going on I guess. :)

This is something I've seen a few times and have been meaning to try for a while myself. Brian Killingbeck from TN, Shane Stacy from AL and Dave McRae from AL all use this approach. I can't imagine it helps with bulk, but it seems like it would definitely save the trouble of switching feet mid-pitch when fending off of a wall, or having to replace your foot in the footloop when reaching a free-hanging section of rope.

I'd be more inclined to try this if I could get my hands on more 5mm spectra... :)


If you have a West Marine store or similar near you you can probably pick up some Amsteel cordage really cheaply and easily.
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