Braking carabiner: aluminium alloy or steel?

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Re: Braking carabiner: aluminium alloy or steel?

Postby Jeff Bartlett » Nov 16, 2011 4:48 pm

LukeM wrote:Ahh, no love for the micro rack? If I can love a micro rack and then also love a simple, surely you can do the same the other way around.


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Re: Braking carabiner: aluminium alloy or steel?

Postby snoboy » Nov 16, 2011 8:53 pm

Caver John wrote:Has anyone ever tried the Raumer Handy braking Biner?


I use it.

I am 220lbs +/- so I do appreciate the extra braking.

It comes with a little welded loop, that attaches to the waist D, and the biner clips to that. If you use that, then you can flip it around, and run 11mm rope in the round end and it works quite well. You could run it that way without the loop, but it would bind on the waist D, especially if you use an OMNI.
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Re: Braking carabiner: aluminium alloy or steel?

Postby paul » Nov 17, 2011 7:38 am

Caver John wrote:^ this is true.

Has anyone ever tried the Raumer Handy braking Biner?
This thing looks interesting, like it would apply more braking than a standard Biner.


Yes, I've been using one for several years with a Petzl Simple. I prfer it to the steel braking carabiner I use to always use before that.

To begin with it was a little jerky but after a bit of use it has become quite smooth in use.

Occasionally, with thicker ropes such as 11mm which the resue team use, I find it exerts too much friction and then I swap to a seel carabiner which I usually carry on my harness. Generally I find the Handy almost perfect and usually it is easy to get just the right amount of friction by raisng or lowering my controlling hand only a small amount. I usually hold the controlling rope in my right hand, palm facing up.

A few times I have been glad I had the Handy when abseiling on "fast" ropes. We tend to use 10mm or 9.8mm ropes and for some reason the ropes we use at the moment seem a bit "fast" despite being the same diameter as others used before by different manufacturers.

In one case where I was caving with others who I don't usually cave with, they had a brand new 9.8mm or 10mm rope which hadn't been cleaned or soaked or used at all and despite having a soft-lock on my Simple (I had begun to lock off in order to add a second carabiner above the descender for additional friction which I have done in the past before starting to use the Handy) I found I could abseil the 100 foot pitch easily while the soft-lock was applied despite using the Handy. :shocked:

The others were able to abseil at normal speed on the rope, all were using Petzl Stops, without touching their Stop handles. Quite a few eybrows were raised!

Another useful feature of the Handy, as shown in "Alpine Caving Techniques", is that in the event of an anchor immediately below you failing while on a multi-rebaly pitch with a second caver abseiling below that rebelay, when the second caver's weight now comes onto the rope, the Stop or Simple can be inverted (as the rope exits at the top of the descender and t sonly by hanging on the descnder while on the rope forces it into the usual "upright" position) and the top caught in a "normal" braking carabiner. This could possibly cause the descender to bend and fail. A Handy, due to its much smaller size, is supposedly able to pevent this happening. I've never heard of such a failure happening, but it is pointed out in "Alpine Caving Techniques".
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Re: Braking carabiner: aluminium alloy or steel?

Postby potholer » Nov 17, 2011 9:48 am

I suppose if such an anchor failure did happen, and a Stop/Simple was pulled through a braking krab, assuming it survived the experience, the main problem of possible uncontrolled descent would come when the rope below was unweighted, so the correct action would be to slap a jammer on the rope above the descender as soon as one recovered from the initial surprise?
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Re: Braking carabiner: aluminium alloy or steel?

Postby Jeff Bartlett » Nov 17, 2011 3:50 pm

potholer wrote:I suppose if such an anchor failure did happen, and a Stop/Simple was pulled through a braking krab, assuming it survived the experience, the main problem of possible uncontrolled descent would come when the rope below was unweighted, so the correct action would be to slap a jammer on the rope above the descender as soon as one recovered from the initial surprise?


I can say, without a doubt, that if a rebelay below me ever fails -- and I find another person's weight dramatically thrown onto my descender -- the first thing I will do is attach every rope clamp and attachment point I own to anything and everything within reach.

Well, possibly the second thing, depending on whether or not I piss myself.
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Re: Braking carabiner: aluminium alloy or steel?

Postby NZcaver » Nov 17, 2011 3:58 pm

Jeff Bartlett wrote:I can say, without a doubt, that if a rebelay below me ever fails -- and I find another person's weight dramatically thrown onto my descender -- the first thing I will do is attach every rope clamp and attachment point I own to anything and everything within reach.

Well, possibly the second thing, depending on whether or not I piss myself.

Don't worry, the person below you will act as a stopper knot. And a target for your urine stream.
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Re: Braking carabiner: aluminium alloy or steel?

Postby LukeM » Nov 17, 2011 4:17 pm

Jeff Bartlett wrote:
potholer wrote:I suppose if such an anchor failure did happen, and a Stop/Simple was pulled through a braking krab, assuming it survived the experience, the main problem of possible uncontrolled descent would come when the rope below was unweighted, so the correct action would be to slap a jammer on the rope above the descender as soon as one recovered from the initial surprise?


I can say, without a doubt, that if a rebelay below me ever fails -- and I find another person's weight dramatically thrown onto my descender -- the first thing I will do is attach every rope clamp and attachment point I own to anything and everything within reach.

Well, possibly the second thing, depending on whether or not I piss myself.


I wouldn't be surprised if the first thing I did was get smashed face first into a rock wall.
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Re: Braking carabiner: aluminium alloy or steel?

Postby paul » Nov 18, 2011 7:20 am

potholer wrote:I suppose if such an anchor failure did happen, and a Stop/Simple was pulled through a braking krab, assuming it survived the experience, the main problem of possible uncontrolled descent would come when the rope below was unweighted, so the correct action would be to slap a jammer on the rope above the descender as soon as one recovered from the initial surprise?


I would imagine that if the descender wasn't damaged due to being caught in the braking carabiner, the fact that the caver below is now hanging on the rope would have the same effect as a bottom belay: i.e., you would stop where you are on the rope anyway until the caver below unweighted the rope.

Once unweighted, I imagine there is a chance that you still would not be able to continue descending depending on how the descender being jammed un the braking carabiner impedes the passing of the rope through the descender or not.

The main problem highlighted in "Alpine Caving Techniques" is that the descender could possible be damaged and either detach from the rope or become uncontrollable in descent.

A project for someond to try and post the results on YouTube? :wink:
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Re: Braking carabiner: aluminium alloy or steel?

Postby LukeM » Nov 18, 2011 8:44 am

paul wrote:A project for someond to try and post the results on YouTube? :wink:


Wait, did you just volunteer? :grin:
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Re: Braking carabiner: aluminium alloy or steel?

Postby Chads93GT » Nov 18, 2011 8:55 am

Someone email that rappelling on a buget kid
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Re: Braking carabiner: aluminium alloy or steel?

Postby potholer » Nov 21, 2011 8:47 am

paul wrote:I would imagine that if the descender wasn't damaged due to being caught in the braking carabiner, the fact that the caver below is now hanging on the rope would have the same effect as a bottom belay: i.e., you would stop where you are on the rope anyway until the caver below unweighted the rope.

Once unweighted, I imagine there is a chance that you still would not be able to continue descending depending on how the descender being jammed un the braking carabiner impedes the passing of the rope through the descender or not.

The main problem highlighted in "Alpine Caving Techniques" is that the descender could possible be damaged and either detach from the rope or become uncontrollable in descent.

I thought that (assuming the descender did survive) uncontrolled descent was thought to be a fairly likely thing when the rope below was unloaded, due to the straightening out of the rope path through the descender.
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Re: Braking carabiner: aluminium alloy or steel?

Postby paul » Nov 22, 2011 7:16 am

potholer wrote:
paul wrote:I would imagine that if the descender wasn't damaged due to being caught in the braking carabiner, the fact that the caver below is now hanging on the rope would have the same effect as a bottom belay: i.e., you would stop where you are on the rope anyway until the caver below unweighted the rope.

Once unweighted, I imagine there is a chance that you still would not be able to continue descending depending on how the descender being jammed un the braking carabiner impedes the passing of the rope through the descender or not.

The main problem highlighted in "Alpine Caving Techniques" is that the descender could possible be damaged and either detach from the rope or become uncontrollable in descent.

I thought that (assuming the descender did survive) uncontrolled descent was thought to be a fairly likely thing when the rope below was unloaded, due to the straightening out of the rope path through the descender.


I don't think you've undestood the problem outlined in ACT (or maybe I didn't explain it very well, which is more likely.

Imagine a pitch with one or more rebelays and you are descending on a section above a rebelay and there is another caver descnding on the section below the rebelay. The anchor on that rebelay now fails.

Immediately, the full weight of the second caver will come onto the rope and will pull the top of your bobbin-type (Petzl Simple or Stop or similar) descender downwards.

If you are using a braking carabiner, there is a chance that the top of the descender will be pulled into the braking carabiner and due to the shock of the failing anchor, it may damage the descender as the bottom of the descnder will still be attached to your harness and the descender's sideplates my become bent allowing the rope to slip off the 'bobbins'.

In ACT it is suggested that this damage may be severe enough that the descender may be released from the rope with obvious bad results. Using a Raumer Handy would mitigate this possibility as its opening is too small to allow the top of the descender to enter.

If the descender was not damaged by the event, you still have the weight of the second caver dangling beneath you on the rope, so I'm pretty sure you wouldn't be able to move, until they released their descender from the rope. A 'bobbin' type descender will still work in a positon where the top is lower than the bottom of the descender and is attached to the harness normally. And in order to achieve that position, there must be an appreciable force on the controlling rope, such as a large weight hanging on it, so it would be an effective bottom belay.

I'm not sure what you mean by "when the rope below was unloaded, due to the straightening out of the rope path through the descender".
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Re: Braking carabiner: aluminium alloy or steel?

Postby potholer » Nov 22, 2011 8:10 am

paul wrote:I'm not sure what you mean by "when the rope below was unloaded, due to the straightening out of the rope path through the descender".

I really wasn't being clear in what I wrote.
I understood that a risk was that if the descender top *is* pulled through a standard braking crab by excessive weight from below without meaningfully damaging the descender, then if the weight below was removed, the descender would be likely to end up stuck in the sideways orientation, where it could give much less friction than in the normal upright position, and where the braking crab was also no longer doing anything useful (something that could potentially also happen if someone lowered themselves onto a rope at a pitchead/rebelay with a non-locked-off descender).

That's really what the comment about jammers was about - someone descending could potentially end up very much stuck on the rope after a belay failure below, but be at risk of a rapid descent (at least as far as the knot on the rebelay) as soon as the rope did become unloaded.
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Re: Braking carabiner: aluminium alloy or steel?

Postby paul » Nov 23, 2011 7:20 am

potholer wrote:
paul wrote:I'm not sure what you mean by "when the rope below was unloaded, due to the straightening out of the rope path through the descender".

I really wasn't being clear in what I wrote.
I understood that a risk was that if the descender top *is* pulled through a standard braking crab by excessive weight from below without meaningfully damaging the descender, then if the weight below was removed, the descender would be likely to end up stuck in the sideways orientation, where it could give much less friction than in the normal upright position, and where the braking crab was also no longer doing anything useful (something that could potentially also happen if someone lowered themselves onto a rope at a pitchead/rebelay with a non-locked-off descender).

That's really what the comment about jammers was about - someone descending could potentially end up very much stuck on the rope after a belay failure below, but be at risk of a rapid descent (at least as far as the knot on the rebelay) as soon as the rope did become unloaded.


Right - I undertsand now where you're coming from. Yes, once the weight below has been removed below, there could be a danger of uncontrolled descent as you suggest. Of course the answer in this situation, is for the caver below and yourself to communicate so that when they unweight the rope, you are already prepared such as by placing a jammer on the rope.
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