Auto-Blocks and Prusiks for Canyoneering

[rcwild]

This thread is intended for general discussion about auto-blocks and prussiks for canyoneering.

Related Threads on our Forums:

Autoblock vs Petzl Shunt (http://www.canyoneering.net/forums/showthread.php?t=380)

[jbliss]

Presumably if you are the first person down in a dry rappel and hit your head and become unconscious, it may save you from hitting the deck. If a contingency anchor is used, then the autoblock will save the person on the rope, and allow for a rescue. The toprope belay has the problem that the ropes could get tangled, especially on a free-hanging rappel, although you are less likely to sustain a head injury on such a rappel. If you are the first one down, there is no way to execute the fireman's belay.

I don't personally use the autoblock, just wanted to think through when it might be reasonable to use it.

Thanks,

jbliss

[mtngoat59102]

I would be really curious to see if test subjects find it easier to apply a mechanical auto block such as the Shunt vs. cord. Most people’s familiarity with 'mechanical' devices makes me suspect that releasing a Shunt at the appropriate moment would be more intuitive than correctly loading a hitching knot. Correctly loading a hitching knot seems something that would take a greater level of competence than a mechanical device.

[rcwild]

The CORRECT use of a Shunt will allow it to lock up, even in a panic situation. If the user holds the lever down while rappelling, it will likely fail as often as a prussik would. The correct way to use a Shunt is to keep your hands off of the lever and simply place your palm on the back of the device and pull it toward you.

[mtngoat59102]

YMMV, I'm guessing that this is highly dependant on the rope you use, conditions, etc. For me: going single strand on 9.5mm or smaller I must push my Shunt away from me to engage the locking action. If I let go of the device (Shunt) completely it will not lock and only follow me down. If you go single strand on a thin rope and use a Shunt as an auto-block this merits tinkering with so you understand your equipment.

[paulsailer]

In my very limited experience I like using an autoblock because of the added feeling of security, and not being dependent on someone else for a firemans's belay for backup.

I also like very much the additional control of speed it gives you, and the additional friction if you want it. You need to positively do something to move downward. It seems much easier to adjust friction and speed with an autoblock. Plus having the ability to stop in mid rappel if you want to.

I can believe in a panic situation you might tend to grab and hold onto a prussik attached to a rope above you. I wonderi you are less likely to hold onto an autoblock which is below you.

I wonder if with experience your instinctive reaction to grab when falling changes to a learned unconscius experience of letting go to stop if you practice enough.

I can see how either device could be dangerous in class c canyons,



The advantage of the prussik (since it is attached directly to the rope and your harness) is it will function a backup even if your rappel device fails completely (for example if you forgot to attach the rap device to your harness) or if the rap device is rigged on an extention which fails ,

Does anyone use both an autoblock and prussik. Belt + suspenders sort of thing.

[rcwild]

The question about autoblock or prussik backups should not be whether to use one 100% of the time or 0%. Use should always be situational. When rappelling off a climbing route when I was guiding, I used an auto-block frequently -- depending on the situation. In canyoneering, I never use one.

No one should ever use one in Class C canyons. Period.

Having said that, if you feel more comfortable/secure using one in Class A and B canyons -- and you understand the problems they can create -- go ahead and use one.

Problems:

(1) In a Class C canyon, if your autoblock/prussik binds up, you may drown whild dangling in a waterfall or stuck in current or a hydraulic.

(2) If you simply lose control of your rappel, any (proper) belay/backup system can stop you. If you are rendered unconscious, an autoblock/prussik will prevent other members of your party from getting you down quickly. Certainly, if you have a contingency anchor set up, they can get you down, but most people don't set up contingencies in Class A/B canyons.

(3) There are some very efficient techniques for passing knots, transitioning from rappel to ascend and ascend to rappel, buddy rescue, etc. that are made less efficient or seriously hindered by an autoblock.

Bottom line: Knowing how to use an autoblock/prussik should definitely be a tool in your toolbox, but actually using one should be situational.

[hank_moon]

No one should ever use one in Class C canyons. Period.

Period? ;) Looks like the assumption here is that every drop in a class C canyon will be wet? Keep it situational, yes, and nevah say nevah!

[rcwild]

Clarification: Never use an autoblock/prussik when rappelling in a waterfall, or when landing in current or a hydraulic (which, of course, only applies to Class C canyons). Period.

Happy now, bro? :D

[hank_moon]

Gol dang it, Hank ... you chap my hide ...

Clarification: Never use an autoblock/prussik when rappelling in a waterfall, or when landing in current or a hydraulic (which, of course, only applies to Class C canyons). Period.

Happy now, bro? :D

Sorry, man...got stock in Burt's Bees n' udder balm. Hardee har...

Much happymore now! (but still leery of "period") ;)

Pedantically yours,

[Spatulator]

What happens after the knot/device stops you? Don't you have to unweight it to get going again? Do you have to bring out your ascender(s) if you stop mid-rappel?

[rcwild]

Depends what you are using. A prussik rigged above your rappel device will be difficult to break loose to start rappelling again. A Petzl Shunt rigged above your device will be easy.

An autoblock or prussik rigged below your rappel device will not be very difficult to break loose. Rigged above your device, it must hold your entire body weight. Rigged below your device, it only has to hold enough force to replace your brake hand; the friction in your device will still hold some of the load.

[dccampen]

Many tests have been done that suggest these hitches are not very effective. One such test involved blindfolded individuals rappelling above a pool. They were instructed to let their prussik/auto-block lock up when they reached the end of the rope.

Not that I am advocating for or against the use of autoblocks. I personally have never used one but ... this is not the first time I have seen the above assertion yet the only test I have seen mentioned in support of the assertion is the one mentioned above; I have never been able to figure out how this test is supposed to prove anything about the efficacy of an autoblock in stopping an out of control rappel. The only thing that I can see this test demonstrating is that an autoblock is not usefull in preventing a blind rappeller from rappeling off the end of a rope.I can't see how this test proves anything, one way or another, about the efficacy of an autoblock for stopping an out of control rappel.

[ratagonia]

Not that I am advocating for or against the use of autoblocks. I personally have never used one but ... this is not the first time I have seen the above assertion yet the only test I have seen mentioned in support of the assertion is the one mentioned above; I have never been able to figure out how this test is supposed to prove anything about the efficacy of an autoblock in stopping an out of control rappel. The only thing that I can see this test demonstrating is that an autoblock is not usefull in preventing a blind rappeller from rappeling off the end of a rope.I can't see how this test proves anything, one way or another, about the efficacy of an autoblock for stopping an out of control rappel.

For those not familiar with it, the test demonstrates that an autoblock knot ABOVE the rappel device is not effective at preventing cavers from rappelling off the end of the rope.

And that is ALL it demonstrates. Dissemination was effective in getting people to change to an autoblock BELOW the rappel device, which at least has the possibility, when properly rigged, of being effective in some kinds of emergencies.

YMMV, etc.

Tom

[rcwild]

I have never been able to figure out how this test is supposed to prove anything about the efficacy of an autoblock in stopping an out of control rappel.

Refer back to the original post in this thread ...

Stopping with a prussik or autoblock requires a negative action -- let go of the hitch. Counter-intuitive. During the test, when rappellers felt the end of the rope pass through their brake hand, they should have instantly let go of the prussik. Even though they knew what was coming, their reaction time was too long to stop them before dropping off the end of the rope. In a real situation -- in panic mode -- will a rappeller have the presence of mind to let go? If they do let go, but it takes a couple seconds to do so, will the hitch lock up or will friction burn through the cord? I don't know the answer.

If the same test was done with an autoblock the failure rate would be even higher. Because an autoblock is controlled with the brake hand, it will come off the rope at the same time the brake hand does.

[Paul Nelson]

Rappelling can be one of the most dangerous activities because a problem can quickly result in you going splat! In caving I have seen various methods come and go for offer saftey while rappelling. Prussik (or autoblock, or shunt) on top (or below) the rappel device and of course the Petzl Stop. Everyone has some type of problem.

Here are some thoguhts.

1) In a panic you squeeze harder and don't let go. The pussik knots, shut, and Petzl Stop all suffer from this problem.

I heard about a device from Australia that requires just the right amount of pressure on the handle to descend. If you press too hard, then it stops descent. This could be a better device.

The link is:
http://www.srte.com.au/pdf/Descenders.pdf

They have a double rope, double brake model. The weakness is you must adjust the cam for the size of the rope. If your in a group using different size ropes and forget to make the adjustment, then that may be a problem.
I will ask my Aussie friends of they have used them and what they think.


2) Once the saftey device is loaded, you must unload it to resume descent. So you better have a means to unload it handy. The Shunt is good because it is easier to unload than a prussik.

3) When placing a knot below the rappel device, take a careful look at the set-up. I saw one person's set-up that if they let go, the knot would hit the desender and not function, or it would caught up into the device causing a new problem.

4) Bad technique. Get the non brake hand off the rope or your descender. Yes it feels nice, but the problem is in a panic you try to squeeze with that hand and not your brake hand.

5) Practice. Load that safety device and practice unloading.

[paulsailer]

An autoblock below the rappel device will do several things:

On the plus side:

It will slow your decent and make it easier to control your decent with your brake hand (unless it is too tight in which case it may make it harder)

It will stop you if you let go of the rope for for some reason (e.g. fall upside down hit your elbow, get stung by bees, get hit by falling rock, etc ) and thus provides some measure of safety backup against those type of situations that could cause you to let go of the rope with your brake hand

It will let you stop by deliberately removing your brake hand from the rope
so that you can use both hands to attend to some necessary task

It will not stop you if you hold onto it while out of control, but it should make it easier to remain in control

On the negative side:

It will make it harder and make it take longer to get off rope-- obviously not a good idea where you need to get off rope fast for safety sake (e.g. class C canyons)

If not rigged correctly it could get caught in your rappel device which would be a real hassle

Personally, I like to use the autoblock because I believe in worse case scenerio where something unexpectedly causes me to let go of my brake hand, I want to know I have a backup

I believe the likelihoodthat I will get into real trouble by letting go of my brake hand in sudden unexpected situation is greater , than the likelihood I will start to go too fast so quickly that I will get out of control by holding onto the autoblock for dear life,

In my very limited experience, I need to apply pressure on the autoblock in order to move at all, so it would be really hard for me to get out of control while using one.

Maybe when i acquire more experise, I will have a different perspective.

[CraigShelley]

Point 1: When I use an autoblock (always below the ATC-XP), I extend my ATC-XP from the harness with a sling. This moves the ATC-XP away from my body and decreases the chance of anything getting into the ATC-XP. The autoblock doesn't even get close to the ATC-XP.

Point 2: When using an autoblock, my left hand MUST loosely nudge the knot down the rappel line. If I remove my hand, it will lock. Some of those writing comments here don't understand this, so they must have never used an autoblock, consequently, are they qualified to comment on when to use or not use an autoblock?

Point 3: When starting a rappel, it can be difficult to pull the rope up and get it into the rappel device. You don't have enough hands available. I've seen people pull up extra rope and then stand on the rope so they have slack. However, if you wrap the autoblock first, it will hold a nice loop of rope for you and make it easy to set up the rappel device.

Point 4: I'm not sure about the study that was mentioned. It would be interesting to have the reference (required? if it is to be stated as fact). However, when you use an autoblock consistently, it doesn't seem at all unnatural to me to let go of it. In other words, if you use an autoblock on a regular basis, it seems like one would be trained to use it properly without thinking. Did the study have beginners using the autoblock that never used it before or experienced users?

Point 5: The two rock climbers that I've trained with (over 50 years of rock climbing experience between them) claim that the Prussic is no longer used and the autoblock is the preferred method.

Point 6: The water situations seem to be the exceptional case. Why not use an autobloc for safety the vast majority of the time?

Point 7: I have never seen a top belay used by canyoneers, only by rock climbers. A fireman's belay is certainly an option, once someone is down, but you are dependent on that person.

Craig Shelley

[rcwild]

Some counter-points ...

Pretty common to hear people say things like, "I've been doing it this way for more than X years in rock climbing and I've never had a problem." That's all well and good, but ... (1) doing it a certain way in rock climbing doesn't relate to the situations encountered in canyoneering, and (2) even if you replace the quote with "... more than X years in canyoneering ..." so what? Luck? It's more valid to look at experiences across the entire international canyoneering community and autoblocks have created problems in some situations.

How many times have people drown or died of hypothermia while descending from a rock climb? Water makes a huge difference.

To suggest that water situations are rare is to take a very narrow view of canyoneering. The ACA uses the analogy of a toolbox. You should have lots of tools in your toolbox (including the autoblock, which we teach) for the myriad of situations you may encounter in canyoneering. But you must understand which tools are appropriate in the situations you encounter. Sometimes (i.e. dry canyons) an autoblock may be appropriate. Other times (i.e. when rappelling in heavy current) it is not.

Yes, it is true that IF you are going to use a pseudo belay, an autoblock below the rappel device is better than a prusik above the device. Some people are actually using a prusik below the rappel device and incorrectly calling it an autoblock. It is better below the rappel device because it only has to replace the force exerted by your brake hand, so it should be easier to release and continue rappelling. Rigged above the rappel device it has to hold body weight, making it much more difficult to release. Autoblock is preferable to prusik because it will release more reliably. A prusik (or autoblock) that binds up while you're rappelling in a waterfall could kill you.

There are times when rigging a hitch like a prusik above the rappel device is appropriate. For example, when you know you are going to pass a knot. Personally, I wouldn't use a prusik. Klemheist or heddon (or Shunt) will work more efficiently. And for passing a knot, rigging this hitch on the end of a Purcell Prusik will make the process very efficient.

I have personally seen autoblocks fail. Usually because (1) cord was too stiff, (2) cord was not wrapped enough times, or (3) cord was wrapped too loose.

Too many people put their faith in a piece of gear instead of honing their skills. Autoblocks are not a panacea.

We shouldn't be talking about autoblocks in a vacuum. Important to consider the entire system. Rope rigged "toss 'n go" and rappeller using an autoblock in strong flow? Big mistake. Rope rigged with a contingency anchor and rappeller using an autoblock? Better, but problems could still occur.

Top rope belays are used by canyoneers ... sometimes. Think about the system. Rappelling in current? Don't tie the end of the belay rope into the rappeller unless the tie-in is easily released.

Fireman belays are very common among canyoneers. Actually a REAL belay because it does rely on a separate person. Autoblocks are pseudo belays.

Gary Storrick Article (http://storrick.cnchost.com/VerticalDevicesPage/Misc/RappelSafetyPost.html)

Trad Girl Article (http://www.tradgirl.com/climbing_faq/safety.htm#rapbackup)

Chockstone Article (http://www.chockstone.org/TechTips/RapBackup.htm)

Note: These articles will provide more information and perspective, but NONE of them are about canyoneering.

[mtngoat59102]

I have to say on this whole topic that the rappelling that I have done after climbing vs. canyoning have a very different feel. In fact, the similarities seem to stop at the actual act of going down the rope using a friction device. It might be kind of a muddy point to make but rappelling while climbing and canyoning have seemed very different in the situations and applicable techniques. I won't argue there is not obvious cross over in principle, but technique application and variety seem vastly different. Am I crazy or have others shared this thought?

I think these types of situations create the back-handed compliments like, 'You Canyoneer like a climber.'

[rambler-joe]

1) if, using an autoblock, you get into trouble and don't let go but do the natural thing and hang on tight, the squeezing action will stop you. The only way to make an autoblock run is to push down on it.
2) on a long rappel, an autoblock restricts your ability to lift the rope and so reduce the braking effect of the rope. This results in a series of very short, jerky, descents. Not good for the rope, the anchor or the rappeller.
3)A prussic above the descender is good for that long rappel but is very difficult to release once it is loaded.
4)The tests done by the British 'health and safety executive' on mechanical devices indicates that they all leave a lot to be desired, with some of the more respected brands cutting the sheath and in one case cutting through the entire rope.:eek:

http://www.hse.gov.uk/research/crr_htm/2001/crr01364.htm

This is a large report, about 160 pages, but has a lot of interesting reading in it.

Horses for courses.
RJ

[Canyonbug]

Maybe I am stirring this up again, but re-reading this forum it constantly talks about using the "Autoblock" as a safety back up. Theoretically and depending on who is talking about it, an autoblock can be defined or understood as several different types of wraps. Picturing an autoblock I think of the first one I learned being a piece of 1" webbing loop or runner wrapped around the rope between your break hand and the rappel device and attached to your leg loop.

What I have understood in the last few years is that an "Autoblock" is actually any type of stop created by wrapping a cord or webbing around the rope. Thus a Valdy, or a French Braid would be considered an autoblock also. Am I right or wrong with my understanding here, please chime in.

That being asked, I have never used an "Autoblock" per se for a safety back up, whereas I have used a French Braid for a safety back up, especially on rappels where I knew I would need to stop 1/2 way down to take care of a problem, (e.g. clean gear, pass knot etc.). I have used this above the rappel device and rig it close enough to be able to release when ready to go down. This also leaves the option if necessary to be able to use the French Braid (or Valdy if used) as the rappel device if necessary.

[ratagonia]

Maybe I am stirring this up again, but re-reading this forum it constantly talks about using the "Autoblock" as a safety back up. Theoretically and depending on who is talking about it, an autoblock can be defined or understood as several different types of wraps. Picturing an autoblock I think of the first one I learned being a piece of 1" webbing loop or runner wrapped around the rope between your brake hand and the rappel device and attached to your leg loop.

What I have understood in the last few years is that an "Autoblock" is actually any type of stop created by wrapping a cord or webbing around the rope. Thus a Valdy, or a French Braid would be considered an autoblock also. Am I right or wrong with my understanding here, please chime in.


Technically, the Autoblock is a specific rope-grabbing knot. It is made by taking a loop of cord or webbing and wrapping it around the rope in a spiral pattern, and clipping BOTH ends.

The far-ranging discussion of rappel backups tends to lump all styles of backups together under the term "Autoblock". This is unfortunate.

I have little experience with rappel backup knots, but it is my understanding that an Autoblock knot below the rappel device, clipped to the leg loop, is the *best* of the many variations available.



That being asked, I have never used an "Autoblock" per se for a safety back up, whereas I have used a French Braid for a safety back up, especially on rappels where I knew I would need to stop 1/2 way down to take care of a problem, (e.g. clean gear, pass knot etc.). I have used this above the rappel device and rig it close enough to be able to release when ready to go down. This also leaves the option if necessary to be able to use the French Braid (or Valdy if used) as the rappel device if necessary.

This sounds like a very practical application of this tool.

Tom

[rcwild]

An autoblock is a specific type of wrap. See: "Knots for Climbers" by Craig Luebben, "Knots and Ropes for Climbers" by Duane Raleigh, AMGA technical manuals, etc.

Unfortunately, the correct use of the term is getting blurred, primarily on the internet. There's also a guy in California teaching the use of a prusik below the rappel device and calling it an autoblock. A prusik is a prusik. An autoblock is an autoblock. Generally speaking, a prusik is not a good choice because it is more likely to bind so tightly that it is difficult to release. Slightly less of a problem below the rappel device than above because below it only has to replace the force required by the brake hand. Rigged above the rappel device it must hold full body weight.

Generically, any hitch used to self-arrest during a rappel should be called a self-belay or pseudo-belay. A french braid can be used for self-belay, but it is a french braid, not an autoblock.

I suppose if the term is used incorrectly long enough, people will start accepting it as correct.

[hank_moon]

A Prusik is a Prusik - proper noun, dude! Pronounced "Proo-zik"

Not "pruh-sick"

[rcwild]

A Prusik is a Prusik - proper noun, dude! Pronounced "Proo-zik"

Not "pruh-sick"


How could you tell how I was pronouncing it from reading my post. :headscratch:

Proper noun? Sure, when you are referring to Mr. Prusik.

[sonnylawrence]

A prusik is a prusik. An autoblock is an autoblock.

Ah, but in some literature there is the "French prusik" which by diagram looks exactly like the "Autoblock." And so the nomenclature is confusing. The literature is inconsistent.
And then what about the verb vs. noun use of the word "prusik," i.e., to ascend a rope vs. the actual hitch. The same goes for "Jumar."

[rcwild]

Ah, good one, Sonny.

Back to the context of Jared's original question ...

If I rig a klemheist below my rappel device for self-belay, is it an autoblock? No.

If I rig a bachman below my rappel device for self-belay, is it an autoblock? No.

If I rig a "regular" prusik below my rappel device for self-belay, is it an autoblock? No.

If I rig a French prusik below my rappel device for self-belay, is it an autoblock? Yes.

[Canyonbug]

An autoblock is a specific type of wrap. See: "Knots for Climbers" by Craig Luebben, "Knots and Ropes for Climbers" by Duane Raleigh, AMGA technical manuals, etc.

I appreciate the comments on this question. When I started out learning ropes I bought "Knots and Ropes for Climbers" by Duane and this is where I first learned about the Autoblock as he describes it.

As mentioned in my first post I have heard canyoneers in the past couple of years use the Autoblock name to refer to any hitch or wrap placed around a rope in order to hold you on rope.

So far the comments posted then would state that an Autoblock is just what it is described in the book as and as Tom described in his post. My French Braid then is that and a Valdy used is just that.

[Canyonbug]

I would entertain any opinions to the contrary if you have a good argument as to why the ones using the names synonymous are correct.

[kambinggurun]

woa this is interesting..

i often used prussik while asending, and that's my only experience with prussik..

could someone please help show me the pic of rappelling with autoblock?
just try to enlighten myself about canyoneering..
my place does not have canyon..
so sad..

[rcwild]

There's a photo on Gary Storrick's website: Autoblock (http://storrick.cnchost.com/VerticalDevicesPage/Ascender/KnotPages/KnotAutoblock.html)

Normally, the carabiner is clipped to the leg loop on the brake hand side of your harness.

You can also connect it to the tie-in point of your harness if you extend the rappel device away from your body with a sling.

What part of Asia are you from?

[Canyonbug]

could someone please help show me the pic of rappelling with autoblock?


Here is a link to Chockstone.com (http://www.chockstone.org/TechTips/RapBackup.htm) with a couple of pics of back ups, one with a prussik and the other with an autoblock

[kambinggurun]

There's a photo on Gary Storrick's website: Autoblock (http://storrick.cnchost.com/VerticalDevicesPage/Ascender/KnotPages/KnotAutoblock.html)

Normally, the carabiner is clipped to the leg loop on the brake hand side of your harness.

You can also connect it to the tie-in point of your harness if you extend the rappel device away from your body with a sling.

What part of Asia are you from?

malaysia..truly asia..

malaysia of south east asia..any idea of it?

anyway do conntinue wit ur discussion..
sorry for my interruption..:D

[rcwild]

I started a thread titled Canyoning in Malaysia (http://www.canyoneering.net/forums/showthread.php?p=6462) under Canyon Beta & Partners

[rambler-joe]

There's a photo on Gary Storrick's website: Autoblock (http://storrick.cnchost.com/VerticalDevicesPage/Ascender/KnotPages/KnotAutoblock.html)

"Normally, the carabiner is clipped to the leg loop on the brake hand side of your harness."

The autoblock is fine if the rappel is 20meters or less, more than that and you can't lift your brake hand to ease off the friction. This results in a very jerky rappel with all the shock loading etc that this produces. For longer rappels the prussik tied above the descender is much better.
R-J

[Canyonbug]

The autoblock is fine if the rappel is 20meters or less, more than that and you can't lift your brake hand to ease off the friction. This results in a very jerky rappel with all the shock loading etc that this produces. For longer rappels the prussik tied above the descender is much better.
R-J

I can't speak for the jerky rappel with the autoblock, but if beginners start using a prussik for a rappel back up with out the proper skills they are going to get stuck on the rope. Once the prussik loads you are going to have to set up an ascending system to unload it. Without the experience to do this or have another learned way, the prussik back up is not a great option for teaching to beginners and I would therefore rather have the jerky rappel with the autoblock. This won't be difficult to get going again once weighted.

[sonnylawrence]

Once the prussik loads you are going to have to set up an ascending system to unload it. Without the experience to do this or have another learned way, the prussik back up is not a great option for teaching to beginners and I would therefore rather have the jerky rappel with the autoblock.

This is a great teaching tool. Let them try the prusik, get it jammed and have to rescue themselves. The rope can always be rigged as contingency if they can't pull it off. They ought to be encouraged to rappel fast to see how easily it hangs. Also, throw fake rocks at them and see how they respond. Hopefully you have a safe place to practise at, like over a deep pool of water. We used to practise this sort of stuff off a bridge with a second rope to catch them.

[rcwild]

... throw fake rocks at them and see how they respond.

Why FAKE rocks? Sonny, you're too nice.

[rambler-joe]

I would therefore rather have the jerky rappel with the autoblock.
Hi Canyonbug. In fact, we teach self rescue techniques before we start on self belays and part of the self belay lesson involves emergency stops with both methods. As for the jerky abseil, would you rather have a your anchor system come apart because of shock loading do a self rescue?
As members of a bush walking club, we have heavy constraints because of our insurance situation. NOBODY goes near a canyon, or other abseil situation, until they are proficient in all aspects of abseiling. At this level, they are still required to have a 'leader' with them for the purpose of setting up anchors etc.
R-J.

[Canyonbug]

...we teach self rescue techniques before we start on self belays and part of the self belay lesson involves emergency stops with both methods...NOBODY goes near a canyon, or other abseil situation, until they are proficient in all aspects of abseiling. At this level, they are still required to have a 'leader' with them for the purpose of setting up anchors etc.
R-J.

RJ
That is great that you teach proper use for the techniques. My main concern in my reply is for those who read these posts and then go into a canyon on their own and end up getting themselves stuck when the Prussik loads. A formal teaching situation is perfect and proper for learning these techniques and having the Anchor set in a contingency so that they can be lowered.

[rcwild]

Set the same thing up today here in not-so-sunny southern California. Students had no problem releasing an autoblock after loading. Only the lightest person was able to release an upper prussik without using a footloop to release the tension.

[rambler-joe]

Set the same thing up today here in not-so-sunny southern California. Students had no problem releasing an autoblock after loading. Only the lightest person was able to release an upper prussik without using a footloop to release the tension.
My argument is not that one system is better than the other but more that each has advantages, and disadvantages, in a given situation. The method of choice, therefore, should be determined by the current situation rather than by personal preferences.
As for those that read these forums, go off into the wild and get themselves into strife, what can you do? Maybe we need a thread for beginners that simply says "GO GET SOME TRAINING".:eek:
R-J

[rcwild]

My argument is not that one system is better than the other but more that each has advantages, and disadvantages, in a given situation. The method of choice, therefore, should be determined by the current situation rather than by personal preferences.
As for those that read these forums, go off into the wild and get themselves into strife, what can you do? Maybe we need a thread for beginners that simply says "GO GET SOME TRAINING".:eek:
R-J

John, you sound like an ACA instructor. Most of our answers start with, "It depends ..."

Pros and cons to both, yes. However, if someone opts for using a prusik over an autoblock, it's especially important they know how to unweight the prusik after it's loaded.

[sanpedro]

Ah, good one, Sonny.

If I rig a French prusik below my rappel device for self-belay, is it an autoblock? Yes.

This post cleared up a lot of confusion for me - in Australia we don't use the term 'autoblock', but I had pictured it as a French prusik. But I was also reading people saying a prussik is not an autoblock Someone mentioned that terms are being blurred by the internet - part of this is that we have people from around the world using terms that are correct in their own countries in an international space.

On holding a shunt to make sure you don't grab it if you fall - shunts today have a small hole beneath the point they are attached to the harness. I tie a small piece of gear cord through this, which I hold between the index and middle fingers of the hand operating my descender - if I fall, it slips through my fingers readily and I'm no longer touching my shunt with my hand

Sorry to dig up an old thread - came here through a 'good posts to read' link elsewhere on the forum.

[rcwild]

Sorry to dig up an old thread - came here through a 'good posts to read' link elsewhere on the forum.

No problem, Pete. Welcome to our forums.

[canyoncaver]

Coming from caving, the whole discussion on autoblocks is quite foreign. As Storrick's "variety of reasons" thread in his autoblock article says, cavers have almost universally rejected them.

I think the Australians hit the nail on the head.

Don't let anyone near a canyon or abseil (rappel) until they know how to rappel and can get themselves out of trouble.

For cavers, this means getting the training, using a device that provides enough fricition, and wearing ascenders for getting out of contingency situations.

It seems like many canyoneers are instead relying on autoblocks as a safety valve. I would contend that there are better solutions.

Safety is not provided by gear, it is provided by your actions and decisions.

[charlybldr]

Coming from caving, the whole discussion on autoblocks is quite foreign. As Storrick's "variety of reasons" thread in his autoblock article says, cavers have almost universally rejected them.

I think the Australians hit the nail on the head.

Don't let anyone near a canyon or abseil (rappel) until they know how to rappel and can get themselves out of trouble.

For cavers, this means getting the training, using a device that provides enough fricition, and wearing ascenders for getting out of contingency situations.

It seems like many canyoneers are instead relying on autoblocks as a safety valve. I would contend that there are better solutions.

Safety is not provided by gear, it is provided by your actions and decisions.

I couldn't agree more. There are certainly legitimate uses for the autoblock and it has its place as one of the many tools in your tool box. But if you're not serious enough to take on the personal responsibility to learn how to rappel safely and in control, all on your own, canyoning is not the sport for you. Try golf or maybe bowling.

[rcwild]

Another lost control on rappel incident. Another call for using autoblocks. So I'm bumping up this thread. Lots of good information. Worth reading the entire thread.

A summary might be something like:


Everyone should learn how to use an autoblock, VT prusik or other form of self-belay. It belongs in everyone's toolbox.
Self-belays may not be appropriate for beginners. Beginners have many other things on their minds when rappelling. Top rope or bottom belays may be more appropriate.
Everyone should know the pros and cons to determine when it is appropriate and when it isn't. Sometimes they can solve problems. Sometimes they can create problems.
Self-belays are not panaceas. They should not be used to compensate for poor technique.
When a self-belay is used, the rope should be rigged releasable.