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Question on Prusik-ing

Original Post
John Maguire · · Boulder, CO · Joined Nov 2008 · Points: 195

A self rescue forum a couple of weeks ago motivated me to practice prusiking up a rope in the event that somehow on belay, you couldn't be lowered or get back on the wall. I found ascending up a single rope pretty straight forward and actually kinda fun.

I'm curious how to ascend two ropes though, say in the event you rapped and couldn't make a ledge. Is there a different technique for tying the prusik around both ropes, instead of just the one?

Randall Chapman · · Grand Junction, CO · Joined Apr 2009 · Points: 1,532

You would have to have two sets of prussics and move them up the rope at the same time.

Edit: I guess if you knew for sure the knot wasn’t going to slip through the anchor at the top you could prussic up the non pull rope in the system but you’re taking a risk.

csproul · · Pittsboro...sort of, NC · Joined Dec 2009 · Points: 330

A prusik (or most any other friction-hitch) works fine around two strands. You may need to adjust the number of wraps.

Chase Roskos · · Golden, CO · Joined Mar 2008 · Points: 90

No need for two sets of prussic cord, just wrap around both strands.

John Maguire · · Boulder, CO · Joined Nov 2008 · Points: 195

Thanks for the replies!

Chuck Manburger · · Denver,CO · Joined Apr 2009 · Points: 130

Try a BACHMANN!?!

Derek W · · Unknown Hometown · Joined Jun 2008 · Points: 20
Chase Roskos wrote:No need for two sets of prussic cord, just wrap around both strands.
+1 Just one set around both ropes
Woodchuck ATC · · Unknown Hometown · Joined Nov 2007 · Points: 3,280

Prusik is fantastic as an ascender knot, but stick tot he Bachman for a backup or descending knot as it unweights so much better. Once the prusik catches tight with weight on a wet rope, well good luck getting it to slide again.

ShibbyShane · · Unknown Hometown · Joined Jan 2009 · Points: 15

Hey John, was that thread over on RC.com? I think I might have seen that. Yeah, I need to practice prussicing (spelling?). I do have a question though: how long should the cord be for a prussic? And for that matter, how long should the cord be for an autoblock (set up below the rappel device)?

Derek W · · Unknown Hometown · Joined Jun 2008 · Points: 20
ShibbyShane wrote: I do have a question though: how long should the cord be for a prussic? And for that matter, how long should the cord be for an autoblock (set up below the rappel device)?
I like a 5.5' or 6' loop for a prussik cord and about half that for an autoblock. If you use a short prussik you can extend it with your daisy or a runner if need be. I also use a shoulder length runner for the autoblock below my rap device quite a bit too, though you may need to extend your device.

If you are new to the ideas of self rescue, this is a great book to check out.
books.google.com/books?id=J…
John Maguire · · Boulder, CO · Joined Nov 2008 · Points: 195

Uhh the thread I was referring to was here on MP. I really don't need another climbing website to enjoy (waste) hours of the day on :)

It wasn't anything informative or spectacular - It was just somebody asking about where to practice self rescue. Someone suggested a back yard tree and it seemed like a great alternative to homework.

Again - I appreciate the advice. I'll have to give this a shot soon. What diameter cord do you use. I'll admit when I played around I was using like 2-3 mil accessory cord that isn't at all climbing spec. I was thinking 6 mil might be a little easier to slide and wouldn't over-tighten so much. Do you guys carry this on every multi-pitch climb. I was thinking about maybe just buying some for a cordellete (sp) since I usually have my knife with me on most routes. I can't see needing it too often, but man would it suck if you did and didn't have any cord!

Chase Roskos · · Golden, CO · Joined Mar 2008 · Points: 90
John Maguire wrote:What diameter cord do you use. I'll admit when I played around I was using like 2-3 mil accessory cord that isn't at all climbing spec. I was thinking 6 mil might be a little easier to slide and wouldn't over-tighten so much.

I use 6mm. Good bite and also more than strong enough.
John Maguire wrote:Do you guys carry this on every multi-pitch climb.
Just about, but not always.
John Maguire · · Boulder, CO · Joined Nov 2008 · Points: 195

OK here is another question:

How many people use a backup knot when they rap? I use an ATC and religiously tie knots in the ends before tossing the rope but I don't really see the need to use an extra safety knot while going down. Is this the norm?

Bobby Hanson · · Spokane, WA · Joined Oct 2001 · Points: 1,230
John Maguire wrote:Do you guys carry this on every multi-pitch climb.
I don't. I have needed to prussik a rope exactly twice. Both times I used slings. They worked great. Once was on one rope, the other time was on two ropes.

John Maguire wrote:How many people use a backup knot when they rap?
I don't. I rappel with both hands on the brake. My partners and I usually provide fireman's belays, especially if the rappel is not straight down.
ShibbyShane · · Unknown Hometown · Joined Jan 2009 · Points: 15

Awesome, thanks for all the advice guys.

divnamite · · New York, NY · Joined Aug 2007 · Points: 90

I always carry a cord for autoblock even tho I don't use it consistently.

I always tie a knot at the end before rappelling if I don't know for sure whether the ropes will hit the bottom or next rap staton.

I always use autoblock if I don't know for sure if the rappell is straight. For example, ropes catch on a branch or stuck in a crack.

Joseph Brown · · Mt. Olive, NJ · Joined Jun 2009 · Points: 30

I'll go without if I'm close to the ground and/or have a fireman's belay from a trusted partner.

Otherwise, an autoblock on rappel is easy insurance. Kinda like a seatbelt - it's only needed when something goes wrong & then it's too late to put it on if you opted to go without.

I've never regretted having an autoblock & it's come in handy several times when having to sort out rope or clean gear that my 2nd couldn't retrieve.

Derek W · · Unknown Hometown · Joined Jun 2008 · Points: 20
John Maguire wrote:What diameter cord do you use. I was thinking 6 mil might be a little easier to slide and wouldn't over-tighten so much. Do you guys carry this on every multi-pitch climb. I was thinking about maybe just buying some for a cordellete (sp) since I usually have my knife with me on most routes. I can't see needing it too often, but man would it suck if you did and didn't have any cord!
I carry 6mm for short prussiks and 7mm for my cordalette. I always have at least one prussik with me wrapped around the bit of my harness that comes from my leg loop through the belay loop. It stays out of the way and its always there if I need it. You could easily put a second one on the other side and you never have to think about it again. I do always carry at least a prussik or runners on a multipitch, just in case. As far as cutting your cordalette for a prussik, I'd be much more likely to just tie an over hand knot in your coralette to shorten it up instead of cutting it. Just my $.02

Joseph Brown wrote:I've never regretted having an autoblock & it's come in handy several times when having to sort out rope or clean gear that my 2nd couldn't retrieve.
+1. Its easier just to make it habit than to wish you had used it when a bird randomly shits on your head and scares you so bad you let go of the rope... ok, that probably won't happen, but rock fall certainly could...
RedRock Rat · · Unknown Hometown · Joined Dec 2006 · Points: 145

Having a backup is a must just about every time I rap. Exceptions are if it is an extremely short rap (20ft or so) or if there is a ground belay (fireman, hip belay, etc.). Otherwise not using one is just like the seat belt comment (try going through the AAJ AR and looking at how many of them are rap accidents that could have been avoided with a backup). When you need it you really need it. If you get in a habit of using it then if something negative does happen you just go by instinct instead of trying to remember how the damn thing works.
Recently I was climbing with 4 friends (2 teams) on a 2 pitch walk off route, I led the first team and we had finished and were waiting up top when we heard that horrible word "Help!". Come to find out that the second party leader had somehow broken his talus while jamming. I rapped and to check him out we were able to lower him to the first station where he rapped to the ground. I had to jug back up the lines roughly 200ft to clean all the second parties gear and get to my partner who didn't know the walk off and I can say if I hadn't been comfortable with friction knots it would have turned a crap day into an epic. Kudos for practicing rescue techniques you just never know.

UIAA Diameter Standards for Accessory Cord
Mil./kN
4/3.2
5/5.0
6/7.2
7/9.8
8/12.8
(1kN= apx. 224 lbs of force)

You can go with a pretty thin cord for you backup just be mindful of the dynamic stress you put on it. A thinner cord tends to provide for a smoother ride but you have to watch the wear and tear more than thicker cords. Knowing webbing/sling friction knots can't hurt either you always seem to have a 2 footer around to give to your partner who forgot his backup.

What are peoples thoughts on extending the rappel device(I've heard it called the "cowbell".)?

Derek W · · Unknown Hometown · Joined Jun 2008 · Points: 20
RedRockRat wrote:What are peoples thoughts on extending the rappel device(I've heard it called the "cowbell".)?
Never heard it called a "cowbell", only a "cowtail". Anyway, I do it most of the time and have never had a problem with it. Its best if your device is within reach, but that isn't mandatory, just makes transferring to another anchor easier. I recommend it if you're backing up below your device.
Brian Adzima · · San Francisco · Joined Sep 2006 · Points: 560

I used to use an autoblock, but seldom do now as it seems to be just extra weight and another thing to fuss with when rapping. A sling, or more often a few raps of the rope around the leg, is quick and requires no extra stuff.

I would take my opinion with a grain of salt, as I also abhor knots in the end of the rope (they often get stuck, are really a hassle when you come up short, and if you use the wrong one they often come undone), and I suspect my opinion on such subjects is a little off of center.

Guideline #1: Don't be a jerk.

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