Author Topic: Hand Jammer Krab  (Read 1008 times)

Offline LarryFatcat

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Hand Jammer Krab
« on: November 24, 2019, 05:39:31 pm »
A trainee asked me what sort of krab to use to attach his hand jammer to footloop/safety link.
I know some people like to attach direct or even a maiillon!!!but I usually teach extra techniques that require a hand jammer krab.
It is used as the long cowstail abroad so the answer is obvious for them but we rarely use ours as a 3rd cowstail.
So what sort? Oval, D, HMS, large small??

Offline Wolfo

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Re: Hand Jammer Krab
« Reply #1 on: November 24, 2019, 05:51:42 pm »
Small Oval Snapgate
Lower Saxony - Harz Mountain Area - Germany

Offline Ian P

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Re: Hand Jammer Krab
« Reply #2 on: November 24, 2019, 06:09:30 pm »
DMM perfecto  ( compact oval, triple action)

https://dmmclimbing.com/Products/Locking-Carabiners/PerfectO

Compact and  secure. Clean nose.

Ian

Offline Cap'n Chris

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Re: Hand Jammer Krab
« Reply #3 on: November 24, 2019, 06:17:18 pm »
Don't use snapgates to connect anything your life depends upon. Here's why:



Backstory 1:
https://ukcaving.com/board/index.php?topic=15351.0

Backstory 2:
http://welshrandomadventures.blogspot.com/2014/09/the-fall.html

Personally I ceased using snapgates to connect anything to anything years ago; who needs the worry? They're cheap and nasty, your life shouldn't be.

_____

As cowstails have been mentioned it's perhaps worth taking the opportunity to reiterate the BCA statement to loosen (or preferably undo, clean and retie) your cowstails knots after every caving trip.
_____

FWIW the background to the combined safety/footloop is now redundant as mid rope rescue techniques have improved massively such that the compelling reason for having such an SRT rig layout has now evaporated. The "standard club UK SRT rig" is anachronistic, tbh.

https://www.goodreads.com/quotes/6521824-learn-from-the-mistakes-of-others-you-can-t-live-long

Footnote: anyone is free to make their own decisions about what they're happy doing - the above is only offered as it wipes away the feeling of compulsion that made it seem worthwhile typing out.
« Last Edit: November 24, 2019, 06:53:54 pm by Cap'n Chris »

Offline Fulk

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Re: Hand Jammer Krab
« Reply #4 on: November 24, 2019, 07:40:16 pm »
Quote
FWIW the background to the combined safety/footloop is now redundant as mid rope rescue techniques have improved massively such that the compelling reason for having such an SRT rig layout has now evaporated. The "standard club UK SRT rig" is anachronistic, tbh.

So – would you care to elucidate these statements? How do 'improved mid-rope rescue techniques' make the combined safety/footloop redundant?

Offline Cap'n Chris

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Re: Hand Jammer Krab
« Reply #5 on: November 24, 2019, 07:56:03 pm »
So – would you care to elucidate these statements? How do 'improved mid-rope rescue techniques' make the combined safety/footloop redundant?

You can easily answer this if you look up why the combined safety/footloop rig was instituted in the first place and how it was then utilised for MRR; now look at how MRR has been effected in the last 15-20 years in more up-to-date reference works. Basically: why was it like that and how was it used back then and why there is no reason to do that anymore in the light of clever kit/ideas. Cave Safe 3 showed how/why the original rig had validity. I imagine any number of CICs would gladly provide a day of coaching on the topic, if you wish :-)

Re: anachronistic - when referring to any recent manuals (especially French/European) you will notice that our overseas counterparts use a far more elegant rig than us, as well as different rigging styles (i.e. post-spit philosophy). UK techniques are very C20th, and at least one region is still very C19th.
« Last Edit: November 24, 2019, 08:29:55 pm by Cap'n Chris »

Offline LarryFatcat

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Re: Hand Jammer Krab
« Reply #6 on: November 24, 2019, 09:04:22 pm »
"FWIW the background to the combined safety/footloop is now redundant as mid rope rescue techniques have improved massively such that the compelling reason for having such an SRT rig layout has now evaporated. The "standard club UK SRT rig" is anachronistic, tbh.

https://www.goodreads.com/quotes/6521824-learn-from-the-mistakes-of-others-you-can-t-live-long"



Wow! Did Eleanor Roosevelt pioneer the the Texas Rope Walking System??

PS: I don't use snap gates underground, great vid

Offline Cap'n Chris

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Re: Hand Jammer Krab
« Reply #7 on: November 24, 2019, 09:10:26 pm »
Wow! Did Eleanor Roosevelt pioneer the the Texas Rope Walking System??

No.

Offline Mike Hopley

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Re: Hand Jammer Krab
« Reply #8 on: November 24, 2019, 09:13:16 pm »
So – would you care to elucidate these statements? How do 'improved mid-rope rescue techniques' make the combined safety/footloop redundant?

I think Chris may be talking about untying your combined safety/footloop to make a length of rope for rescue manoeuvres. For example, for a counter-balance or a hauling system. Because of this idea, some people recommend using knots that can easily be untied.

Techniques for such situations have improved. A long cowstail or footloop can be used as a counterbalance during a mid-rope pick-off, for example. The various pick-off methods have also become easier by using a foot ascender to help with positioning.

As for the original question: avoid using a snapgate as the upper krab in Chris's video. Clipping a snapgate cowstail/safety into a locked carabiner or maillon is okay, as is clipping it directly into the jammer (e.g. the current Petzl Basic). If it makes you nervous though, by all means use a locking carabiner or direct tie-in.

Offline andrewmc

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Re: Hand Jammer Krab
« Reply #9 on: November 24, 2019, 09:40:15 pm »
I tend to find DMM triple actions are great above ground but an absolute disaster underground. Petzl ones seem much more resilient to grit and mud.

Petzl Sm'd twist lock is what I would use if I was rebuilding my SRT kit; I currently use a Petzl oval triact but it makes it more fiddly than it needs to be to use as a third cowstail. Am'd if you insist on massive carabiners (I have twistlock Am'd krabs as cowstails).

If horrific mud is likely then I find the twistlocks get tricky not because they stop working but because you can't get a grip on them. I intend to get so Vertigo via ferratta krabs for my cowstails for next year's Dachstein...

In terms of shape I think it probably makes bugger all real difference. I think ovals are more prone to everything unnervingly going 'clunk' when weighted and you move around (as things shift on the krab) but I could be misremembering.

Offline andrewmc

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Re: Hand Jammer Krab
« Reply #10 on: November 24, 2019, 09:42:24 pm »
Don't use snapgates to connect anything your life depends upon.

Agree, but your life should never depend on your hands ascender (alone) :)

Offline Cap'n Chris

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Re: Hand Jammer Krab
« Reply #11 on: November 24, 2019, 10:01:29 pm »
Petzl Am'd twist lock is what I would use if I was rebuilding my SRT kit; I currently use a Petzl oval triact but it makes it more fiddly than it needs to be to use as a third cowstail. Am'd if you insist on massive carabiners (I have twistlock Am'd krabs as cowstails).

Agreed: not a fan of Triacts but Am'd TLs aren't much better either though as they are a mare in-cave with mud ingress/being fiddly etc.. Best left in the bin, imo.

Re: "3rd cowstail" - can you clarify whether you are referring to using a semi-static handjammer/footloop connection or an additional dynamic rope cowstail?

More generally, have you tried these (link below)? I like them very much and have lots and have used them for years. Petzl Vertigos are excellent too, btw; easy/quick to use but twice as costly as the Grivels.


« Last Edit: November 24, 2019, 10:12:17 pm by Cap'n Chris »

Offline Fulk

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Re: Hand Jammer Krab
« Reply #12 on: November 24, 2019, 10:45:25 pm »
Quote
You can easily answer this if you look up why the combined safety/footloop rig was instituted in the first place and how it was then utilised for MRR; now look at how MRR has been effected in the last 15-20 years in more up-to-date reference works. Basically: why was it like that and how was it used back then and why there is no reason to do that anymore in the light of clever kit/ideas. Cave Safe 3 showed how/why the original rig had validity. I imagine any number of CICs would gladly provide a day of coaching on the topic, if you wish :-)

Re: anachronistic - when referring to any recent manuals (especially French/European) you will notice that our overseas counterparts use a far more elegant rig than us, as well as different rigging styles (i.e. post-spit philosophy). UK techniques are very C20th, and at least one region is still very C19th.

That doesn't answer my question.

Offline Cap'n Chris

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Re: Hand Jammer Krab
« Reply #13 on: November 24, 2019, 11:04:41 pm »
Mike Hopley answered it so I don't have to. There's more but he wrote enough to make the case. It is debatable* that people ought to know the capabilities/strengths/weaknesses and application(s) of their gear and its repertoire of techniques in all situations (progression/rigging/derigging/rescue) prior to going live underground with it but I'm a stickler and most people rely on never having to solve things which might, but usually don't, crop up. And a lucky rabbit's foot on a snaplink isn't going to change that. But it might. Fingers crossed. :-)

* No it's not. It's indefensible that they should.

Offline andrewmc

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Re: Hand Jammer Krab
« Reply #14 on: November 24, 2019, 11:34:44 pm »
Re: "3rd cowstail" - can you clarify whether you are referring to using a semi-static handjammer/footloop connection or an additional dynamic rope cowstail?

I use a dynamic 'safety cord' (same rope as cowstails but different colour) and Petzl dyneema footloop. 'Third cowstails' in the sense that you can clip bolts etc directly with the handjammer krab; useful when you need two long cowstails (like getting over the rock on the OFD1 bolt traverse, or rigging traverses where the bolts are just slightly too fat apart). Or standing up higher on a bolt (using the footloop).

Quote
More generally, have you tried these (link below)? I like them very much and have lots and have used them for years. Petzl Vertigos are excellent too, btw; easy/quick to use but twice as costly as the Grivels.

I have not tried the Grivels, although others I know have; for 95% of my caving the twist locks (and even the triacts) are fine. It's only in Dachstein mud where I can't actually grip the things I have a problem...

Offline alastairgott

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Re: Hand Jammer Krab
« Reply #15 on: November 25, 2019, 07:28:19 am »
I imagine any number of CICs would gladly provide a day of coaching on the topic, if you wish :-)

I'm sick of getting wet while doing SRT, could I have a training session on the drier aspects of SRT. :smartass:
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Offline Cap'n Chris

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Re: Hand Jammer Krab
« Reply #16 on: November 25, 2019, 08:46:33 am »
I imagine any number of CICs would gladly provide a day of coaching on the topic, if you wish :-)

I'm sick of getting wet while doing SRT, could I have a training session on the drier aspects of SRT. :smartass:

Yes. Rig away from water. £argesum please, invoice on way.
« Last Edit: November 25, 2019, 09:14:44 am by Cap'n Chris »

Offline nearlywhite

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Re: Hand Jammer Krab
« Reply #17 on: November 25, 2019, 09:38:30 am »
Small grivel plume, have used a snap gate in the past but moved to locking mainly for peace of mind that the kit doesn't disassemble in a crawl/tackle bag. I'm the same as Andrew in using dynamic, and often use it to clip in as a 3rd cowstail (or rather 2nd long), or just into the knot at a pitch head - convenient for long limbs in tight rifts.

Offline Mike Hopley

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Re: Hand Jammer Krab
« Reply #18 on: November 25, 2019, 12:53:18 pm »
One other thing to consider when choosing your hand jammer setup: will you use your jammer to rig traverses? Or even just for progression along a traverse line sometimes, such as when it's sloping upwards?

In these cases, the jammer can load badly during a fall -- potentially levering it off the rope. To prevent this, you can clip the rope through the safety-cord carabiner. This could matter a lot, if the jammer is your only point of attachment.

Let's say you have a maillon connecting your safety cord and jammer. How will you make the jammer load safely in these situations?

There was a good video of some "realistic" tests falling on caving equipment, but I can't find it now. I think it was French again, maybe Petzl or EFS. It was filmed in some climbing / rope access centre (Petzl Institute?). It had slow-motion footage of jammer detachment. Does anyone have the link?

Offline A_Northerner

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Re: Hand Jammer Krab
« Reply #19 on: November 25, 2019, 02:19:59 pm »
I use a Petzl OK oval krab with triact lock as I often use it as a point of attachment on a traverse line (my short is VERY short for comfort/working with short arms on freehangs), I found that a screwlock I'd often leave undone due to absent-mindedness afterwards, so an auto-lock works better for me. Using an oval also allows for a spare pulley krab if needed on a rescue.
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Offline Mike Hopley

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Re: Hand Jammer Krab
« Reply #20 on: November 25, 2019, 04:28:48 pm »
when referring to any recent manuals (especially French/European) you will notice that our overseas counterparts use ... different rigging styles (i.e. post-spit philosophy).

That's an interesting comment. Which things would you say stand out as different rigging styles, and how have they been influenced by changes in anchors?

The main thing I can think of is the use of Dyneema. Also some details I'd just consider "good practice", like double anchors at the start/end of a traverse -- I'd say there's less emphasis on that over here.

Maybe also the preferred methods of placing the rigging? Using a hand jammer to rig/de-rig traverses seems somewhat uncommon among UK cavers.

I guess you also have stuff like umbrellas, but those seem rather specialist.

Offline LarryFatcat

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Re: Hand Jammer Krab
« Reply #21 on: November 25, 2019, 04:41:36 pm »
Petzl Am'd twist lock is what I would use if I was rebuilding my SRT kit; I currently use a Petzl oval triact but it makes it more fiddly than it needs to be to use as a third cowstail. Am'd if you insist on massive carabiners (I have twistlock Am'd krabs as cowstails).

Agreed: not a fan of Triacts but Am'd TLs aren't much better either though as they are a mare in-cave with mud ingress/being fiddly etc.. Best left in the bin, imo.

Re: "3rd cowstail" - can you clarify whether you are referring to using a semi-static handjammer/footloop connection or an additional dynamic rope cowstail?

More generally, have you tried these (link below)? I like them very much and have lots and have used them for years. Petzl Vertigos are excellent too, btw; easy/quick to use but twice as costly as the Grivels.



it looks like it might be a lot more fiddly to get out of a rope bight (the place you are supposed to attach for a rebelay)??
« Last Edit: November 25, 2019, 04:52:02 pm by LarryFatcat »

Offline LarryFatcat

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Re: Hand Jammer Krab
« Reply #22 on: November 25, 2019, 04:45:49 pm »
I imagine any number of CICs would gladly provide a day of coaching on the topic, if you wish :-)

I'm sick of getting wet while doing SRT, could I have a training session on the drier aspects of SRT. :smartass:

We've been offered https://www.alter-rock.co.uk/labyrinth-cave/ for SRT training and it even has a dry cave!!

Offline LarryFatcat

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Re: Hand Jammer Krab
« Reply #23 on: November 25, 2019, 04:48:12 pm »
One other thing to consider when choosing your hand jammer setup: will you use your jammer to rig traverses? Or even just for progression along a traverse line sometimes, such as when it's sloping upwards?

In these cases, the jammer can load badly during a fall -- potentially levering it off the rope. To prevent this, you can clip the rope through the safety-cord carabiner. This could matter a lot, if the jammer is your only point of attachment.

Let's say you have a maillon connecting your safety cord and jammer. How will you make the jammer load safely in these situations?

There was a good video of some "realistic" tests falling on caving equipment, but I can't find it now. I think it was French again, maybe Petzl or EFS. It was filmed in some climbing / rope access centre (Petzl Institute?). It had slow-motion footage of jammer detachment. Does anyone have the link?
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Offline Brains

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Re: Hand Jammer Krab
« Reply #24 on: November 25, 2019, 07:00:32 pm »
On the snap / screw debate, I use screw gates for everything apart from my cow tails and breaking krab. I have seen on more than one occasion people that should have known better hanging from a screw gate cow tail tighten it up out of boredom and over zealous checking while carrying out a manoeuvre, only to find the gate is now jammed leaving them hung up, possibly under water. I have also seen screw gates jam both open and locked due to silt ingress. For a paying punter or groups of novices I can imagine the peace of mind screw gates give might out weigh these factors, but with well trained competent groups snaps are fine. Yes I know they can unclip in some circumstances, and knowing that I can avoid those situations. For preference a wire gate IMO is the best on a cow tail. As a climber I would be happy to take a lead fall on to a wire gate, so don't see an issue here (Ordinary snaps can vibrate open, but a wire will stay closed).