Changing over from climb to rappel (frog)

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Changing over from climb to rappel (frog)

Postby glowbug » Sep 24, 2012 9:04 pm

I've practiced the changeover from climb to rappel before and never had a problem with it. Then the other weekend, at the bottom of Neversink, I was the last one going up and left my pack. 20ft from the bottom...UGGH. This is kind of embarrassing to talk about on a public forum but I promise you I am not a complete idiot, I am just trying to trouble shoot something that I haven't been able to get a verbatim answer for.

I was able to unweight the croll to remove it after attaching the safety, but even with locking off my rappel rack the most I could do was down climb down one ascender at a time - if I removed one, the other was too far up to unweight enough to remove and just be on the rack (my ascender attachment is actually on the really short side so that makes no sense)... I would've had to have just one point of contact (not that I think there's anything wrong with that, but I know that a lot of people stress having 2 points) and put the rappel rack on just below the one ascender - even then I think the ascender would've been too weighted...and I think I tried that. I could have passed a knot no problem - I could unweight one at a time, it was just that last step of un-weighting the remaining ascender to be able to use the rappel rack !!

I settled on downclimbing (and that was one exhausting downclimb and a slow climb back out) and everything was just fine - I'm confident I would've eventually found a way to do it the correct way if I'd had the patience, but with the pack so close (especially that last 5ft on the stretchy rope) I wasn't about to be patient. I just kept putting one ascender directly on top of the other (it involved using the QAS attachment as a footloop and weighting that - doing acrobatics). It was embarrassing and tiring. Luckily no one else saw it; doing that for more than that 20ft would have sucked a lot more. My last resort was going to be to munter down, I thought that might put the munter closer to my body than the ascender and help unweight the ascender (would that have even worked?).

In retrospect I think my safety may have stretched a lot since the last time I practiced this as it is on accessory chord, and I wasn't thinking and could have used my cow's tail to make it shorter... but I was looking online and in OnRope to try and find a detailed step-by-step on how to changeover from climb to rappel (while on a bouncy rope in a free drop and not able to brace against a wall - all the guides I could find were from rappel to climb which is not the problem here - or for passing knots or switching ropes - I can do all that with my setup) and haven't found one. Can anyone go over this step-by-step and describe the difference in lengths between your QAS and ascender attachments? I am going to go over my system and try to recreate the problem, I think all the times I have practiced have been against a wall where I could brace to help un-weight my gear. Given the caves I have recently done I should not be having this problem, I feel like such a caving idiot :(

Thanks :)
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Re: Changing over from climb to rappel (frog)

Postby NZcaver » Sep 24, 2012 10:12 pm

Welcome to the forum. Don't feel too bad. Stuff happens to all of us, and you're not the first one to post about this on the forum.

What type of rack are you using? I assume a full size/long rack? Are you using a caving style harness with a low attachment point? If so, it may be an issue with footloop/cowstail lengths and/or the changeover technique you're using.

See this page for one possible solution for next time.
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Re: Changing over from climb to rappel (frog)

Postby Chads93GT » Sep 24, 2012 10:23 pm

Most important step is to have your upper ascender on the long cowstail. To start the changeover clip the short end of the cowstail into the hand ascender and slide the whole thig up as high as it can go then start the changeover process. Once the rack is fully rigged in you unclip the short end of the cowstail from the long. This will put all the weight on the rack. Click the link for more detailed instructions.
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Re: Changing over from climb to rappel (frog)

Postby Stridergdm » Sep 24, 2012 10:26 pm

Hmm, I really don't think I'm going to attempt a step by step as I'm sure I'd confuse things even further.

But, I would say that in general a 20' downclimb shouldn't be that hard. The bounce would certainly complicate things, but for me, in general a 20' downclimb doesn't take much longer than changing over and descending. I'd suggest that in addition to solving the change over problem, working on this might be useful in those limited edge cases.

Also, I don't use a "QAS". My frog is simply a croll and right-handed petzl ascender (another "no-no" some will tell you :-)

Ok. I guess I will try to describe what I do. (going on memory here.. too lazy to get out my frog and try it right this second.)

1) put upper ascender at about 80% of my normal maximum (guessing on the distance here)
2) Sit on croll
3) weave rope into micro-rack (which for me is directly attached to my D-mallion, another "no-no" :-) and do a hard lock-off.
Do this beneath my croll (since obviously no slack above it.)
4) Stand up in foot loop and as I do, pull on release on croll
5) pop rope out of croll
This should put my weight fully on my rack at this point.
6) lower the upper ascender to just above my rack (don't always do this, but generally do)
7) Unlock my rack, let it slide an inch or so... do a soft-lock off.
8) thumb upper ascender off the rope.
9) undo soft lock and descend.

If I'm focused I can do the above in under 20 seconds. BUT that wasn't on 140' of rope where bounce will have some impact on all the steps.

If you have a long rack, then well.. I can't help you. I'm WAY out of practice on that. (hmm, I probably should swap racks and practice a bit.)

I should note too that I have what some refer to as a 3 cowstail system (ascender on its own tether and then a Petzl Energia for my "normal" two tethers.

As for feeling like an idiot... No, an idiot would have had the problems you did and not asked for help. Everyone (ok, maybe 1 or 2 folks) can always learn and improve their technique.
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Re: Changing over from climb to rappel (frog)

Postby snoboy » Sep 25, 2012 12:21 am

On first take it sounds to me like the attachment to your upper ascender is too short - at least too short to be used in pairing with a rack.
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