Two Points of Contact Rule

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Re: Two Points of Contact Rule

Postby Extremeophile » Nov 18, 2013 6:05 pm

cavedoc wrote: for those that use lockers, do you lock them? Sure, if they're autolocks,but for a standard one? I have a locker on both cowstails, but it's mostly so I don't have to think about which is which and I know I have one around if I needed to switch it out. I don't routinely lock it. (putting on flame proof cave suit)

This is why I use a particular type of autolocker. I think a screw lock gate is slow and impractical for crossing rebelays with Euro style rigging. I might even argue that it would be less safe than using a non-locker. Likewise, an autolocking mechanism that requires two hands is also impractical. But with the right type of autolocker you can cross rebelays with the same speed and efficiency as you can with non-lockers, and you have the added security that they can't easily unclip themselves.
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Re: Two Points of Contact Rule

Postby NZcaver » Nov 19, 2013 1:02 am

Extremeophile wrote:
cavedoc wrote: for those that use lockers, do you lock them? Sure, if they're autolocks,but for a standard one? I have a locker on both cowstails, but it's mostly so I don't have to think about which is which and I know I have one around if I needed to switch it out. I don't routinely lock it. (putting on flame proof cave suit)

This is why I use a particular type of autolocker. I think a screw lock gate is slow and impractical for crossing rebelays with Euro style rigging. I might even argue that it would be less safe than using a non-locker. Likewise, an autolocking mechanism that requires two hands is also impractical. But with the right type of autolocker you can cross rebelays with the same speed and efficiency as you can with non-lockers, and you have the added security that they can't easily unclip themselves.

I have mine set up the same way as Roger. I think he's saying just because there's a screw lock gate on the cowstail, doesn't mean it needs to be locked and unlocked every time a rebelay is crossed. I leave my short cowstail carabiner unlocked and use it just like a non-locker, but with the option of locking it when needed.
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Re: Two Points of Contact Rule

Postby paul » Nov 19, 2013 7:27 am

NZcaver wrote:
Extremeophile wrote:
cavedoc wrote: for those that use lockers, do you lock them? Sure, if they're autolocks,but for a standard one? I have a locker on both cowstails, but it's mostly so I don't have to think about which is which and I know I have one around if I needed to switch it out. I don't routinely lock it. (putting on flame proof cave suit)

This is why I use a particular type of autolocker. I think a screw lock gate is slow and impractical for crossing rebelays with Euro style rigging. I might even argue that it would be less safe than using a non-locker. Likewise, an autolocking mechanism that requires two hands is also impractical. But with the right type of autolocker you can cross rebelays with the same speed and efficiency as you can with non-lockers, and you have the added security that they can't easily unclip themselves.

I have mine set up the same way as Roger. I think he's saying just because there's a screw lock gate on the cowstail, doesn't mean it needs to be locked and unlocked every time a rebelay is crossed. I leave my short cowstail carabiner unlocked and use it just like a non-locker, but with the option of locking it when needed.


Same here. Short cowstail has just a non-locking biner, and long one has a locker (not Autolock). When passing rebelays I clip in both but do not do up the locking mechanism. Some caves I've been in had many pitches and many, many rebelays so if you add up the few seconds it takes to screw up the lock and then unscrew again afterwards multiplied by the number of rebelays multiplied by the number of cavers adds up to an appreciable amount of time. I only screw up the lock when clipped in with the long cowstail and moving around like when hauling gear, etc.

Personally I don't like Autolock biners underground as I have tried one in the past and it's mechanism failed due to mud and grit.
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Re: Two Points of Contact Rule

Postby Extremeophile » Nov 19, 2013 10:58 am

paul wrote:Personally I don't like Autolock biners underground as I have tried one in the past and it's mechanism failed due to mud and grit.

I have autolocks on both cowstails. I use an autolock D as my main clipping point (Petzl Omni). I also use an autolock on my descender (Petzl Freino). Rarely have I had a problem with any of them.
I agree with the argument about screw locks and the extra seconds needed per clip and unclip adding up. This argument does not apply to the use of auto lockers.
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Re: Two Points of Contact Rule

Postby Shane S » Nov 20, 2013 3:36 pm

I’ve been ridiculed for not having an extra QAS besides my croll and upper on my frog system. While I’m perfectly capable of down climbing into a change over and maintaining two points of contact, I don’t feel that two points is always necessary and certainly not an extra QAS dinging around in the way. I feel that if an ascending device is fully seated and weighted, that it is adequate. I typically do maintain the two points just because it’s what I was taught, but if I was in a freezing waterfall or a waterfall that restricted my breathing or similar situation, I wouldn’t bat an eye at relying on one point and doing a faster change over. It would be interesting to find out where this rule came from and what it’s based on. :shrug: :shrug:
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Re: Two Points of Contact Rule

Postby Anonymous_Coward » Nov 20, 2013 6:24 pm

The people that ridiculed you need to educate themselves a little better.
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Re: Two Points of Contact Rule

Postby PeterFJohnson » Nov 20, 2013 6:47 pm

Shane S wrote:...but if I was in a freezing waterfall or a waterfall that restricted my breathing or similar situation, I wouldn’t bat an eye at relying on one point and doing a faster change over. It would be interesting to find out where this rule came from and what it’s based on. :shrug: :shrug:


You hear this argument a lot. I am not sure how going to one point of contact makes a changeover any faster on a frog though? Are you refering to a changeover from ascent to descent using a full sized rack? That seems like the only time where disengaging the chest ascender might save you time.

And of course, I realize it was a hypothetical example, but it is usually best to Not Rig The Waterfall
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Re: Two Points of Contact Rule

Postby cavedoc » Nov 20, 2013 8:04 pm

Shane S wrote:I’ve been ridiculed for not having an extra QAS besides my croll and upper on my frog system.


What Andy said.

Your upper ascender on the long cowstail is your QAS. You don't need a second one. Now since you're in TAG and may be using a long rack, then having a second upper ascender may be a good idea. Doing a changeover with a long rack is challenging while maintaining the two points rule. If you have a micro, bobbin, etc then you're good as is.
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Re: Two Points of Contact Rule

Postby hunter » Nov 21, 2013 7:08 pm

On the original question, due to having ascenders slip unexpectedly on muddy ropes, slide when I accidentally hit the catch and come off on a tricky j-hang I have an inherent wariness of ascenders and always use two points of contact with ascenders while I sometimes use a single cowstail. For the same reasons I'd recommend that anyone use two points of contact until they feel they have enough experience to risk there life by using one.

I fall under the non-locker on short cowstail and locker (not auto) on long. There are many circumstances where I am happy with a non-locker and/or the unlocked locker but there are also many circumstances where I am flailing around or not paying attention to my cowstails or free climbing while clipped to something where I lock the carabiner on my cowstail because I feel it might be possible to twist it off the rope. If you don't feel comfortable judging each situation yourself (it is your life) than I'd use two lockers.

Derek,
I tend to feel that you should always keep more significant figures in life safety application so 0.71 is really 0.707106781186548 or more precisely, the sqrt(2)/2. :)

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Re: Two Points of Contact Rule

Postby ian mckenzie » Nov 22, 2013 6:09 pm

Shane S wrote:I’ve been ridiculed for not having an extra QAS besides my croll and upper on my frog system. While I’m perfectly capable of down climbing into a change over and maintaining two points of contact, I don’t feel that two points is always necessary and certainly not an extra QAS dinging around in the way.

It is, of course, possible to respect the two-point-contact rule without having an extra QAS, or even a cowstail. You can unclip your safety line from the foot-jammer and clip it into the anchor (or rope loop) i.e. use it as a cowstail.
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Re: Two Points of Contact Rule

Postby LukeM » Dec 23, 2013 11:39 am

Does anyone have a method of maintaining two points of contact when rigging a traverse, as when rigging horizontally on a ledge toward the lip of a pit from a rearward bolt? Other than with an autostop bobbin I can't think of a convenient way to do this with a descender. (avoiding pull rope through, lock, unlock, pull rope through...)

One method is to use a tethered ascender and manually engage the cam as when down-climbing, but this is only one point of contact, and it seems much more likely to run into trouble dangling from a floppy traverse line than when static and completely weighted. Does anyone use two ascenders in this situation?
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Re: Two Points of Contact Rule

Postby paul » Dec 24, 2013 7:10 am

LukeM wrote:Does anyone have a method of maintaining two points of contact when rigging a traverse, as when rigging horizontally on a ledge toward the lip of a pit from a rearward bolt? Other than with an autostop bobbin I can't think of a convenient way to do this with a descender. (avoiding pull rope through, lock, unlock, pull rope through...)

One method is to use a tethered ascender and manually engage the cam as when down-climbing, but this is only one point of contact, and it seems much more likely to run into trouble dangling from a floppy traverse line than when static and completely weighted. Does anyone use two ascenders in this situation?


I generally clip my long cowstail to the loop of rope on the traverse which I have just tied and connected then tie an Cavers' Butterfly on the rope beyond this point and clip my short cowstail to this. If the lengths between anchors are right (for me anyway) I can usually connect that same knot to the next anchor. Then move my long cowstail to the new knot and repeat.
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Re: Two Points of Contact Rule

Postby ian mckenzie » Jan 4, 2014 7:07 pm

Am thinking that most here would use their Petzl Stop on a traverse pull, with the brake disabled. But you could also use a Munter hitch on the traverse rope itself thru a biner on your harness, paying it out until you reach the pitch head. Then clip in your foot ascender, using its tensioned tether as your main support when placing your pitch head anchor.

Or have your mate put you on belay.

If it's a narrow ledge you'd want intermediate anchors (chocks?) on the line to reduce a nasty pendulum in the event of a stumble.
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Re: Two Points of Contact Rule

Postby LukeM » Jan 6, 2014 9:24 am

Why would you disable the brake on a Stop for this? Wouldn't the brake be exactly the kind of thing needed to quickly and conveniently "stop" to rig into a traverse bolt for instance? That's what I meant when I brought up the Stop specifically as a solution.
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Re: Two Points of Contact Rule

Postby ian mckenzie » Jan 12, 2014 2:41 pm

You disable the brake so that you have both hands free, because on a traverse the Stop is hard to feed as your body weight is not on the rope. If you are traversing down a steep slope to an edge there is really nowhere to fall to. But if you are on a ledge where you could fall, the Stop with the brake disabled would still arrest your fall - after all, we rappel with the brake handle depressed, no? It is of course a simple matter, and standard procedure, to tie off the Stop - whether you have the brake on or not - when you reach the pitch edge and are ready to place your anchor.
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