Rack lock off problems

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Rack lock off problems

Postby southernjoel » Sep 12, 2005 2:03 pm

While using an old SMC steel rack with round bars, I have had problems doing lock-offs(soft). When I do a lock off,a small bight of rope gets pinched between the first and second bars behind the main rope and at times seems almost impossible to pull back out. It takes extreme effort in pullling the rope out to start rapelling again. There is small rubber spacers between the first and second bars,but I am not sure if this has anything to do with it. Thanks...Joel
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Postby David_Campen » Sep 12, 2005 2:22 pm

This happens even without a spacer. Many people will form a long bight of rope below their rope hand and step in the bight to use their weight to pull the rope free.
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Rack locking off too hard

Postby KENTO » Sep 12, 2005 2:42 pm

Without having been there to watch you do this , I think I can recommend you try this...Take your Q.A.S. out and attach it about 10 inches above the rack, reverse the free end of rope back over the top of rack , make a small over hand loop in the free rope below the rack , insert whichever foot you prefer in this loop , grab the rack and stand in the loop. This will result in a rapid popping the rope free, your foot and the loop will get sucked up into the rack and your Q.A.S. will now be out of reach about 3 feet over your head. This is good for you if you are 5 feet off the ground in your backyard practicing stuff like this where you should be. If you are in a waterfall pit it is hard to say what will kill you first hypothermia or Harness Hang Syndrome.
You can probably figure this out for yourself but I included this worsecase scenario because it can , it has happened.
You would also be wise to study what movements of your body on rappell are causing the rope in soft lock mode to shift into not so soft lock...Have fun...Be Careful
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Postby Scott McCrea » Sep 12, 2005 2:43 pm

How does the rope get jammed down there? Is it when you are changing over and you stand up to release your upper ascender?

One sure way get rid of this problem is to use a hyperbar. The other is a slight modification of your technique. But that depends on how you answer the above questions. :wink:
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Postby NZcaver » Sep 12, 2005 2:44 pm

This seems to be a fairly common problem with or without spacers. It usually takes a little brute force to tug the rope back out (or wrapping it around your foot, as just mentioned by David). You might find it a little easier to pull or push the top of the rack away from the main line while tugging the rope out with your other hand.

You could also try doing a soft lockoff by bringing the rope over the rack (like you already do) but rest it on the top bar rather than letting it slot between the bars - just don't pull down too tight on the rope as you do this. Assuming you use a J rack and not a U rack, bring the rope back under the bottom bar and across the top bar a second time. That gives you a kind of double-wrap soft lock. This may work OK with your rack, or it may not. Try it in a controlled situation first, like hanging from a tree. You might consider replacing the top bar of your rack with a hyperbar, it makes locking off a lot easier.

Hope this helps... :caver:
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Postby southernjoel » Sep 13, 2005 4:29 pm

Scott,

Yes, it really becomes stuck good when I am doing changeovers. Takes just about all my strength to pop it back out,and when it does release....it creates a violent jerking action. Definately not a smooth technique...lol.
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Postby cob » Sep 13, 2005 7:04 pm

get the hyper bar, the sure cure for this problem.
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Postby Scott McCrea » Sep 13, 2005 9:37 pm

Ok, first, the spacers on your rack do make it a little easier for the pinch to happen. But the also make it a little easier get out of a pinch. So, I wouldn't worry too much about their effect on the pinching.

The hyperbar will definitely solve the problem, but they cost money and add weight and bulk to your gear.

Let's assume that we are talking about a ropewalker and a standard J shaped rack.

As for getting out of the pinch, the technique already mentioned of stepping in a loop and using your body weight to pull the rope out works just fine. It is jerky and not smooth. Be sure your QAS is attached above the rack. And be sure that you hold the bottom bar up as you do this manuver. Holding the bottom bar up will keep the rack from moving down the rope.

There is another technique that works great for me. It's a little controversial but done properly... The rope gets pinched when you stand up to release your QAS using a footloop attached to an ascender that is placed below the locked off rack. Tensioning the rope below the rack pulls the wrap down into the pinch. You can avoid this by not locking off your rack. Well, let me say that a little differently–unlock your rack before you stand up to release your QAS.

All you have to do is, unlock your rack while holding the bottom bar up, ie pushing the bars together. Attach your knee ascender to the rope below the rack. Step up, slide the QAS down so when you sit your weight will be on the rack, all the while holding the bars together. Remove the knee ascender. Remove the QAS. Rappel.

Really the only difference with this technique is that you are using your hand to hold the bars together rather than the rope holding the bars together. And, you need to be able to operate your ascenders with one hand.

If you choose to try this, try it in a controlled and safe place first. It's really easy once you get the hang of it and it will improve your change over times.
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Postby Ralph E. Powers » Sep 18, 2005 7:49 pm

This is the kind of thing that get the Bobbin lovers shaking their heads and glad that they use that type of device over a rack.
While both devices have their plusses and minuses neither can rightly be said to be better than the other.

As far as when your lock off is "stuck" / "jammed" or whatever a suggestion (in addition to the others) is to have your handled ascender to help assist getting your weight off the rope ... place it just above the rack and step up into the foot-loop then unjam. Be sure not to allow yourself to lower down past the point where it's now difficult to get the ascender off the rope. :roll:
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get a micro rack

Postby reece » Sep 19, 2005 9:54 am

and... this problem NEVER happens with a micro-rack. And for all of you out there who say that a micro-rack doesn't offer enough friction or variability, if Joe Ivy could do Golondrinas on a micro, I'm convinced that it'll work in nearly every circumstance.
--
these are not the opinions of Great Basin NP, or the NPS, just mine.
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Postby cob » Sep 19, 2005 6:29 pm

Scott McCrea wrote:The hyperbar will definitely solve the problem, but they cost money and add weight and bulk to your gear.
.


Scott, with all due respect, they cost money? I got mine for about $5, about 4 yrs ago. Considering what a rack costs?

Weight: what are they... an ounce more? at most?

Bulk: considering how bulky the rack is to begin with...

As you yourself said, "the hyperbar will definitely solve the problem,..."

I believe in and practice the "KISS" principle: "Keep It Simple Stupid", quite simply because I am.

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Postby Scott McCrea » Sep 19, 2005 6:51 pm

Tom,$5 is a great deal on a hyperbar. I would buy one at that price, just to have one. Where did you get it?

Everyone has personal preferences. Personally, I usually find it simpler to adjust my technique rather than add more gear. I have my share of stupid too. :wink:
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Postby cob » Sep 19, 2005 6:58 pm

Scott McCrea wrote:I have my share of stupid too. :wink:


I do not recall... it was at a week long NCRC in Ark... Maybe it was longer ago than that. Or maybe it was more than that?(I am getting senile in my old age)

In so far as "share of stupid" goes... are we not cavers?

To each their own... tom
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Re: get a micro rack

Postby Tim White » Sep 20, 2005 8:40 am

reece wrote:if Joe Ivy could do Golondrinas on a micro, I'm convinced that it'll work in nearly every circumstance.


True, a micro-rack MAY “work in nearly every circumstanceâ€
Be safe,
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Postby chh » Oct 11, 2005 12:30 pm

Just a quick addition to the hyperbar scenario. I don't use a hyperbar because I find that it makes the rack even more or a pain to pack somewhere than it already is. Instead take a non-locking 'biner and clip it to the top of your rack, the smaller the better. With all six bars snugged and the rope going underneath the bottom bar (obviously) bring your brake hand up and clip the rope through the 'biner. At 157 pounds I don't go anywhere on a standard SMC 6 bar. This, of course, wouldn't work if you are not using a "J" style rack. If you are using the "U" style, get the hyperbar.

A few people I know who use racks regularly have a stitched sleeve for thier racks in their cave packs. With a hyper bar sticking out, it just seems to catch on stuff, especially while caving in between multiple drops. With a 'biner that stashes on your harness or in the bag this is less of a problem. I leave the rack at home when doing multiple drops in cave - but that's just me. A few of my friends use their 6 bars for everything and also use 'biners for additional friction. Plus, you can definitley get a single 'biner for 5 bucks just about anywhere. In fact, I bet you have one lying around your house right now.... ;)

Also, the advice about making sure the rope isn't underneath the top bar before you load your rack is about the simplest (cheapest) and most sound advice. But, things don't always work out like you want them to.

Just my $0.02

Cave Softly,

-chh
Your words of caution are no match for my disaster style!
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