Is there a changeover

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Postby Stridergdm » May 22, 2007 8:55 pm

fuzzy-hair-man wrote:The mistake that I see about half of the first time beginners (using the short rack version) do is try to thread thier rack upside down so I'd perhaps make the point that they need to think carefully about which end they thread the rack from, it's probably more obvious with your Petzl rack which has an eye, but less obvious with U racks.

I'm not sure what would happen if they did load it but I suspect they would be stuck on rope not going anywhere very quickly as it would compress the bars together.

Good Job :grin:


It doesn't go anywhere. Trust me. ;-)

Fortunately you generally make that particular mistake only once. :-)

One other comment on the instructions, again applicable to the NCRC rules, but I'd recommend anyway.

After undoing the croll, take the hard lock off the rack, descend 1-2" to make sure there's no problems (like worse case scenario, you suicide rig the rack), then either soft-lock or simply stop, remove the upper ascender and continuing descending.

Taking this extra step becomes habit, but can help you catch a few mistakes that could potentially be fatal.

Overall though I want to say this is great. Teaching changeovers can always be a pain since often the person learning is 5' or more above your head, making hands on instruction tricky.

Thanks.

Oh and as for the tape, I'm guessing to ID it. I use red and purple tape myself.
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Postby adleedy » May 22, 2007 9:06 pm

Stridergdm wrote:Oh and as for the tape, I'm guessing to ID it. I use red and purple tape myself.

BINGO, All my gear is ID'd with red reflective tape :grin:
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Postby fuzzy-hair-man » May 22, 2007 9:25 pm

Stridergdm wrote:After undoing the croll, take the hard lock off the rack, descend 1-2" to make sure there's no problems (like worse case scenario, you suicide rig the rack), then either soft-lock or simply stop, remove the upper ascender and continuing descending.


Whilst I agree with the idea, often after sitting down on the descender they will not have 1-2" of slack in the cord to allow them to descend this distance before releasing the the upper ascender. Perhaps a better idea may be get them to down prussik thier upper ascender then release thier lock whilst still protected by thier upper ascender.

I'm not 100% but I'd think a suicide rigged rack (even if locked off) would pop off the rope as soon as you weighted it.

Stridergdm wrote:Teaching changeovers can always be a pain since often the person learning is 5' or more above your head, making hands on instruction tricky.


I get them to do the changeover when they are only about 3 ft or so off the ground that way it easy to see what they are doing and you can give suggestions and if the worst comes to the worst they can stand on a ladder or your shoulders etc.

The other thing I suggest is that in the short rack version, prior to releasing the chest ascender that they down prussik thier upper ascender as low as possible and using a trial and error approach see how low they can place thier hand ascender and still be able to release the Croll. In a well set up frog this shouldn't need to be done but not everybody's system is that well set up*. This avoids (if possible) the case where they sit down on the descender and the hand ascender attachment line goes tight in which case they need to stand up and try again (the most tiring bit and where in my experience most people get stuck). Another trick is to wrap the foot loop a couple times around your foot or feet to effectively shorten your foot loop a bit (it squeezes your feet but does work).

* our club uses communal gear so in most cases the lengths aren't what they should be.

I guess this is all making a nice simple/consise proceedure more and more complicated and confusing :oops:
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Postby Stridergdm » May 22, 2007 10:00 pm

Yes, I would agree to lower the upper ascender before letting out slack. Good point.


As for a suicide rack, depending on how it's locked of, it can certainly remain "safe" until unlocked.

As for 3' or 5', same basic thing. Still less than convenient. And you obviously want them high enough off the ground they don't cheat and use the ground to help. :-)

Following up on the thumbing down the upper ascender. Definitely. After lots of trial and error I have an idea of how low I can lower it and still stand up and release the crowl, etc.

Sounds silly but I LIKE practicing my change-overs. :-)
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Postby NZcaver » May 23, 2007 1:14 am

Good discussion, guys. :kewl:

It's almost a given that cavers old and new will frequently need to fiddle with ascender positions on the rope to get it right - the trick is not to get frustrated and/or tired out. Thanks to NCRC training I adopted the practice of thumbing down the upper ascender, unlocking the descender and rappelling a little to make sure it's safe, and then releasing the ascender completely. I suggest steps 4a and 4b be expanded slightly to incorporate this technique, at least as an option.

I also suggest a slight modification to step 3b, for ergonomic reasons. Grasp and pull down the catch on the Croll with your right thumb BEFORE standing up, so when you do stand the cam pops open easily. Believe me, it's much easier to teach this way than having people stand and strain themselves while "searching" for the catch to release their Croll!

Now this next bit is not really a suggestion, just an observation. Being as I'm usually a "short descender" guy, the technique shown for the longer rack wasn't what I was initially expecting. It is certainly a known method I've seen used before, but the default method I use is different. I begin by adding the (notorious) third ascender/Prusik/whatever to the rope between the two other ascenders. Then I pop the Croll right off, and carry on as normal.

The method shown in the link has the advantage of being somewhat simpler, and doesn't require a third ascender - but I really do wonder about the value of leaving that slack Croll on the rope. It gets in the way of threading and locking off the rack, which can cause frustration for beginners or anyone else. In a way I suppose I'm also questioning the value of *always* needing MORE than one gripping point of attachment (ascender) for purely safety reasons. Without the loose Croll in place, are you likely to accidentally release your (loaded) upper ascender and plunge to your death? Or maybe there's a sudden shock load resulting in your upper ascender failing (or severing/stripping the rope) - but somehow having a Croll clipped in saves the day? If so, why then is it OK to commonly use a single ascender as a "QAS" all by itself? (On second thoughts, don't answer that last bit. Or if you do, at least post it in one of the QAS threads!) :big grin:

Just wondering how likely these failure/saviour modes are in the real world, that's all. Carry on... :wink:
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Postby fuzzy-hair-man » May 23, 2007 1:54 am

NZcaver wrote:I also suggest a slight modification to step 3b, for ergonomic reasons. Grasp and pull down the catch on the Croll with your right thumb BEFORE standing up, so when you do stand the cam pops open easily. Believe me, it's much easier to teach this way than having people stand and strain themselves while "searching" for the catch to release their Croll!

:agree: It also stops them trying to open the cam after they have stood up, ie try to open as you stand in the foot loop.

NZcaver wrote:The method shown in the link has the advantage of being somewhat simpler, and doesn't require a third ascender - but I really do wonder about the value of leaving that slack Croll on the rope. It gets in the way of threading and locking off the rack, which can cause frustration for beginners or anyone else. In a way I suppose I'm also questioning the value of *always* needing MORE than one gripping point of attachment (ascender) for purely safety reasons. Without the loose Croll in place, are you likely to accidentally release your (loaded) upper ascender and plunge to your death? Or maybe there's a sudden shock load resulting in your upper ascender failing (or severing/stripping the rope) - but somehow having a Croll clipped in saves the day? If so, why then is it OK to commonly use a single ascender as a "QAS" all by itself? (On second thoughts, don't answer that last bit. Or if you do, at least post it in one of the QAS threads!) :big grin:

Just wondering how likely these failure/saviour modes are in the real world, that's all. Carry on... :wink:

Ewwww cool a great big .......
Image

I think at least in part coming up with a list of places where you can be attached using a single ascender is more difficult, and probably more confusing than a blanket statement that says you must have two teethed points of attachment at all times.

I suspect that teethed ascenders are only liable to disconnect whilst you are moving up the rope if you are stationary you're reasonably safe on one.
But I'm still going to follow the rules :nono:
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Postby Ralph E. Powers » May 23, 2007 12:27 pm

Stridergdm wrote:Overall though I want to say this is great. Teaching changeovers can always be a pain since often the person learning is 5' or more above your head, making hands on instruction tricky.

Thanks.

That's why I prefer to have two ropes with the "instructor" on one and the student on the other... and at the same height. The instructor can do a change-over slowly so that the student can watch and copy. Or depending upon the student just listen to verbal instructions or just simply watch and see how it's done. But I prefer to be up beside the student... even if we're only 5 feet off the ground.
Later I get them to make the change-overs at higher and higher points on the rope (or is it lower and lower? :-) )
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Postby Stridergdm » May 23, 2007 7:25 pm

Ralph E. Powers wrote:
Stridergdm wrote:Overall though I want to say this is great. Teaching changeovers can always be a pain since often the person learning is 5' or more above your head, making hands on instruction tricky.

Thanks.

That's why I prefer to have two ropes with the "instructor" on one and the student on the other... and at the same height. The instructor can do a change-over slowly so that the student can watch and copy. Or depending upon the student just listen to verbal instructions or just simply watch and see how it's done. But I prefer to be up beside the student... even if we're only 5 feet off the ground.
Later I get them to make the change-overs at higher and higher points on the rope (or is it lower and lower? :-) )



I agree with a 2nd rope being nice when possible. (until you both start to spin until your backs are to each other and have to ask others to twist you about and hold your feet. ;-)

But, your final comment I actually think is more interesting.

I think many of us end up teaching "backwards" i.e. starting at the bottom and ascending and then changing over to descending. But realistically, how many caves go this way. :-)

I'd love to be able to teach like I learned years ago, with a nice convenient balcony so you can start at the top and descend first. And you can also access the victi^H^H^H^H student from above and below.

Just a thought.
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Postby fuzzy-hair-man » May 23, 2007 8:37 pm

Stridergdm wrote:But, your final comment I actually think is more interesting.

I think many of us end up teaching "backwards" i.e. starting at the bottom and ascending and then changing over to descending. But realistically, how many caves go this way. :-)

I'd love to be able to teach like I learned years ago, with a nice convenient balcony so you can start at the top and descend first. And you can also access the victi^H^H^H^H student from above and below.

Just a thought.


We have such a balcony (we are able to practice in a gym with stairs to the inside of the roof) and this is the way we do it, not so much because you descend first in a cave but because a changeover from descending to ascending is easier and it means they have a nice progression from harder to easier manouvers building confidence at each step. We do change overs before rebelays and redirects and knot crossings even though rebelays and redirects are probably easier purely because as soon as they have learnt changeovers we can start to take them on trips involving a straight abseil, so we get them in a cave and loving caving sooner. :kewl:
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Postby Ralph E. Powers » May 23, 2007 9:14 pm

Stridergdm wrote:I agree with a 2nd rope being nice when possible. (until you both start to spin until your backs are to each other and have to ask others to twist you about and hold your feet. ;-)

What I do to halt the spin cycle is (as instructor) to spread my legs/feet wide enough apart to have the student in the middle of them... NEVERMIND how it looks okay! At least the spin is arrested. Like wise while balconies are great and trees are just as good, IMO nothing beats the side of a nice cliff -- however short-- to practice on/off of. For one it gives the student (particularly the noobie) a sense of how it is in the cave... up against rock and utilizing it to your advantage. One foot splayed out to toe the rock (if you're close-enough in a "free-hang" ) will stop the spin. Otherwise you'll be up against the rock and learning how to deal with that.
I try to emulate as close as possible conditions (save total darkness) in a cave.
It helps the student focus better in my experience.
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