Had a problem with my frogging system, any ideas?

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Had a problem with my frogging system, any ideas?

Postby Ch33s3n1p » Jun 12, 2011 10:25 am

I was frogging with my neck strap a little looser than it should have been and the carabiner on my croll rotated into an odd position and jamed the cam open. It stayed on the rope, but did not grab. I use an oval, non-locking biner and a 1" adjustable webbing loop, is there a better way to set up your lower ascender?

Also, do ya'll tie into the rope with your cow's tale every 10-20 feet? I've read about it, but never actually met anyone who does. Seems like a terribly inefficient thing to do. I've thought about pushing a prusik along above my top ascender. Any thoughts on that?

Thanks
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Re: Had a problem with my frogging system, any ideas?

Postby rlboyce » Jun 12, 2011 11:24 am

http://technology.darkfrontier.us/Vertical/Frog/
http://technology.darkfrontier.us/Vertical/FrogGanter/

Never seen anyone use a carabiner between their harness link and their croll before. Perhaps there are those who do, but my setup works perfectly fine by putting the croll directly on the harness link.

Don't know why you'd ever do that with your cowstails. IMO two ascenders are plenty safe enough. LOL, I would not go caving if I had to always do that with my cowstails.
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Re: Had a problem with my frogging system, any ideas?

Postby Carl Amundson » Jun 12, 2011 12:42 pm

Ch33s3n1p wrote:I was frogging with my neck strap a little looser than it should have been and the carabiner on my croll rotated into an odd position and jamed the cam open. It stayed on the rope, but did not grab. I use an oval, non-locking biner and a 1" adjustable webbing loop, is there a better way to set up your lower ascender?

Also, do ya'll tie into the rope with your cow's tale every 10-20 feet? I've read about it, but never actually met anyone who does. Seems like a terribly inefficient thing to do. I've thought about pushing a prusik along above my top ascender. Any thoughts on that?

Thanks

I have never seen a croll with an biner between the ascender and the D-link.
I would attach the croll directly to the D-link. That is how it is designed to work.
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Re: Had a problem with my frogging system, any ideas?

Postby Mugger » Jun 12, 2011 2:06 pm

junkman wrote:
Ch33s3n1p wrote:I was frogging with my neck strap a little looser than it should have been and the carabiner on my croll rotated into an odd position and jamed the cam open. It stayed on the rope, but did not grab. I use an oval, non-locking biner and a 1" adjustable webbing loop, is there a better way to set up your lower ascender?

Also, do ya'll tie into the rope with your cow's tale every 10-20 feet? I've read about it, but never actually met anyone who does. Seems like a terribly inefficient thing to do. I've thought about pushing a prusik along above my top ascender. Any thoughts on that?

Thanks

I have never seen a croll with an biner between the ascender and the D-link.
I would attach the croll directly to the D-link. That is how it is designed to work.

I've seen this setup used to attach a croll to an alpine harness (no D-link used).... Not very efficient, but it works.
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Re: Had a problem with my frogging system, any ideas?

Postby ron_miller » Jun 12, 2011 2:09 pm

You didn't mention what type of harness you're using, but for frogging, a "caving" or "frog" style harness (e.g. Petzl SuperAvanti or Fractio, OnRope1 Goliath) is recommended for efficiency. This type of harness is brought together in the front with a half-round maillon or Petzl Omni style carabiner, which as previous posters have stated should be connected directly into the bottom hole of your Croll.

Note that this style of harness has a low point of attachment, making it unsuitable for rock climbing, but much more efficient for frogging. For frogging, you want your Croll as low as possible to maximize the distance between your two ascenders, increasing the "bite" you get with each cycle. Also, the sloppier the bottom attachment is (think too many links in a chain), the more height you lose every time you sit.

I would also suggest that you consider using an "H-type" chest harness (e.g. PMI or GGG), which keeps webbing off your neck. The webbing in the harness gets threaded directly through your upper Croll hole.
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Re: Had a problem with my frogging system, any ideas?

Postby NZcaver » Jun 12, 2011 2:31 pm

Ch33s3n1p wrote:I was frogging with my neck strap a little looser than it should have been and the carabiner on my croll rotated into an odd position and jamed the cam open. It stayed on the rope, but did not grab. I use an oval, non-locking biner and a 1" adjustable webbing loop, is there a better way to set up your lower ascender?

Was this non-locking oval carabiner connected to the top or the bottom hole of your Croll? From your post I assume the top (between Croll and chest harness/loop). If so, try swapping it for a smaller (tiny) carabiner or screw link. It doesn't need to be rated - almost anything will do. Or you can try simply threading the chest harness webbing directly through the hole, as many of us do.

If (as others assume) the issue is with the connection between the Croll and your harness, there are a few things you should know. Firstly, a non-locking carabiner is not appropriate for a primary life support link here - you really should be using something which locks. Secondly, as others have said, the Croll is normally connected directly to the half-round (or delta-shaped) screw link which holds your caver-style seat harness together at the front. If you are using a traditional climber-style seat harness instead, things will be a little different. Those harnesses will work, but are less efficient and practical for ascending with a frog system and once you try a caving harness you'll see why.

If you are using a climber-style seat harness for right now, I suggest connecting the Croll to the harness with a 7mm oval screw link. It's reasonably compact and probably your best option. DON'T USE ONE FROM THE HARDWARE STORE! Buy only rated Maillon Rapide screw links, usually available from caving vendors like Inner Mountain Outfitters, OneRope1, Karst Sports, etc.

I don't tie into the rope every 10-20 feet, and I don't know cavers who do. Where did that advice come from?

PS just saw Ron's reply, which explains the harness setup in more detail. I agree with his recommendation on the H-style chest harness, connected directly to the Croll. That's what I use.
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Re: Had a problem with my frogging system, any ideas?

Postby Ch33s3n1p » Jun 12, 2011 2:45 pm

Thanks for all the input guys. I guess I wasn't clear in the original post. I'm using a PMI Pit Viper harness with the croll attached directly to the half-round screw link. That setup works soooo much better than my sport climbing harness with a screw link attached to the belay loop. I'll try just running the neck strap directly through the top hole of the croll... the only reason I didn't do that to begin with was to avoid nylon on nylon contact. But if the carabiner might jam the ascender open that is more of a concern than the rope brushing against a piece of webbing that could fail without consequences.

Tying into your main rope sounds ridiculous, but I'm sure I read it somewhere. Maybe it was in the literature that came with one of my ascenders.
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Re: Had a problem with my frogging system, any ideas?

Postby NZcaver » Jun 12, 2011 2:49 pm

Ch33s3n1p wrote:I'll try just running the neck strap directly through the top hole of the croll... the only reason I didn't do that to begin with was to avoid nylon on nylon contact.

If the chest harness webbing is threaded directly though the Croll, I don't see how that would be nylon-on-nylon contact. You should be fine.
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Re: Had a problem with my frogging system, any ideas?

Postby Ch33s3n1p » Jun 12, 2011 3:04 pm

NZcaver wrote:
Ch33s3n1p wrote:I'll try just running the neck strap directly through the top hole of the croll... the only reason I didn't do that to begin with was to avoid nylon on nylon contact.

If the chest harness webbing is threaded directly though the Croll, I don't see how that would be nylon-on-nylon contact. You should be fine.



Sounds good, I'll try it next time. I have tons of extra webbing, I'll try sewing a basic chest harness to keep the weight off my neck.
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Re: Had a problem with my frogging system, any ideas?

Postby Extremeophile » Jun 12, 2011 3:30 pm

It's common practice in big wall rock climbing to tie into the rope, using something like a figure eight on a bight, every 20-30 feet when cleaning a pitch while ascending. In this case you're using two ascenders but it's common to have to disconnect one or the other when negotiating traverses or roofs, which would leave you with only one point of attachment. The backup is only valid because the rope is dynamic and can save you if the second ascender suddenly fails. Tying into a static rope, as is used in caving, is not a suitable backup. Most people accept two ascenders as a safe minimum, and many people carry a third ascender or Prusik cord in case they need to cross a knot. If there's a mid-rope knot then it may be rigged with a loop that can be clipped with one of the cowstails in place of using a third ascender.

I'm assuming the rock climbing scenario above is what you may have read. I haven't seen a publication recommending this approach for caving.
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Re: Had a problem with my frogging system, any ideas?

Postby Extremeophile » Jun 12, 2011 3:36 pm

NZcaver wrote:
Ch33s3n1p wrote:I'll try just running the neck strap directly through the top hole of the croll... the only reason I didn't do that to begin with was to avoid nylon on nylon contact.

If the chest harness webbing is threaded directly though the Croll, I don't see how that would be nylon-on-nylon contact. You should be fine.

Perhaps ther's some risk that the rope will rub the chest harness webbing and burn though it. I think most people would agree that once your weight is on the rope, the force of gravity tends to keep the top of the croll and the rope from making much contact. Besides, as has been pointed out already, the chest harness is not life supporting.

The Petzl Serprntine chest harness goes throuh the top of the Croll twice, but it doesn't move, so the Nylon on Nylon contact there is irrelevant.
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Re: Had a problem with my frogging system, any ideas?

Postby NZcaver » Jun 12, 2011 3:54 pm

Extremeophile wrote:Perhaps ther's some risk that the rope will rub the chest harness webbing and burn though it. I think most people would agree that once your weight is on the rope, the force of gravity tends to keep the top of the croll and the rope from making much contact. Besides, as has been pointed out already, the chest harness is not life supporting.

Oh, right. In theory I guess that's possible, but I've never seen it happen. Probably for the reason you stated.
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Re: Had a problem with my frogging system, any ideas?

Postby Ch33s3n1p » Jun 12, 2011 4:03 pm

Extremeophile wrote:The backup is only valid because the rope is dynamic and can save you if the second ascender suddenly fails. Tying into a static rope, as is used in caving, is not a suitable backup.


A few years ago when I made my frogging system I had a "screamer" attached to the short cow's tail via a screw link with a locking biner on the other end. I used tape to keep everything lined up on the major axis. My thought was that the screamer would give me the dynamic-ness necessary to absorb a fall. I don't know how well that would work, but I'm glad I never tested it with a fall.
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Re: Had a problem with my frogging system, any ideas?

Postby Extremeophile » Jun 12, 2011 4:52 pm

Ch33s3n1p wrote:
Extremeophile wrote:The backup is only valid because the rope is dynamic and can save you if the second ascender suddenly fails. Tying into a static rope, as is used in caving, is not a suitable backup.


A few years ago when I made my frogging system I had a "screamer" attached to the short cow's tail via a screw link with a locking biner on the other end. I used tape to keep everything lined up on the major axis. My thought was that the screamer would give me the dynamic-ness necessary to absorb a fall. I don't know how well that would work, but I'm glad I never tested it with a fall.

Sounds like it would work... at least once. It's common practice these days to use dynamic rope for cowstails so that it can absorb the force of an inadvertant fall. Some people still use non-dynamic cowstails, which can generate catastrophic forces in short but high fall factor falls. There are many threads discussing appropriate materials for cowstails.
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Re: Had a problem with my frogging system, any ideas?

Postby Jeff Bartlett » Jun 12, 2011 6:14 pm

Extremeophile wrote:Perhaps ther's some risk that the rope will rub the chest harness webbing and burn though it.

No.
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