Emergency backup ascenders, Petzl Tibloc?

[fuzzy-hair-man]

OK - I got bored and pulled out some of my toys...

Show off ! We need a green smiley (ie envy)

So the Tibloc does work with a 'normal' pulley that's useful to know thanks for that!

- Or, you could just get a Mini Traxion...

True, it's an option, I could proably cope with taking Tibloc(s) on every vertical trip I don't know whether I'd end up taking a Mini Traxion (although it's not big)

[NZcaver]

So the Tibloc does work with a 'normal' pulley that's useful to know thanks for that!

Just be aware that rigging method is not in any books or instructions (that I know of). Came up with that all on me own, I did.

The loading on the top of the lower carabiner is a little unorthodox, but it doesn't seem to be a problem. It's not like it's under 3-way loading or anything. Just make sure both the upper carabiners are identical.

- Or, you could just get a Mini Traxion...

True, it's an option, I could proably cope with taking Tibloc(s) on every vertical trip I don't know whether I'd end up taking a Mini Traxion (although it's not big)

Yeah, good point mate.

I'm the same way - the Tibloc goes with me on the harness, but the Mini Traxion lives in my medium-weight rescue kit, along with some other goodies.

Gearrrrr juuunkie...!!!

[cob]

Ok guys, it has been 10 yrs or so since I took My Level 1 NCRC training (I was never able to afford both the time and the money at the same time to get 2 & 3) so I am sure things have changed, but I have a couple questions:

Question #1: This thread was started concerning using the tibloc as an emergency back-up ascender. It was pointed out that there have been some problems with it tearing the rope if not used properly. As near as I can ascertain from the thread, this is still a problem. Is weight so much of an issue that you are willing to risk tearing the sheath on the only thing that keeps you (and those that follow) alive?
I once dropped a 40' virgin pit and within 5 secs of reaching the bottom was completely slimed from head to toe (sank into the muck almost to my waist). My Petzl safety almost got me inverted when after 10' it stopped working. My 8 mil prusiks slipped a little bit, but got me out just fine. Seeing as I rarely climb icy ropes, I can not say, but for now I will stick with the prusiks.

Question #2: In my NCRC L-1, we were taught our rigging by Ken (can't remember his last name) and he seemed to be, like me, a c-o-b who was somewhat distrustful of all these "new fangled gadgets". He used rescue ascenders but sparingly (he liked his prusik knots)(I am sure RAs work just fine). But the one thing he beat into our heads repeatedly was that "You never use anything in a haul system or safety line, that can cut the rope!" And here you are, using something that you acknowledge can cut the rope, as a PCD. When things go wrong in a rescue, you don't have time to set your PCD "properly". It either works like it is supposed to, or people die.

Or at least, that is what I was taught. Have things changed that much?

tom

[hank moon]

The main difference between a TIBLOC and the other Petzl toothed-cam ascenders is the lack of a spring in the TIBLOC. This means the user must manually set the cam against the rope to avoid possible sheath damage. This setting is indicated in the technical notice by the diagram showing a thumb pressing against the upper part of the TIBLOC. Keep in mind it is an emergency ascender, not a lightweight substitute for regular ascenders. It takes practice to use correctly and efficiently, and we all know that forced practice in an emergency can be a heap of fun. If you own some of these, get out and practice in a safe environment before taking them underground. I find a Texas-style system works best for me - YMMV.

[hank moon]

Question #1: This thread was started concerning using the tibloc as an emergency back-up ascender. It was pointed out that there have been some problems with it tearing the rope if not used properly. As near as I can ascertain from the thread, this is still a problem. Is weight so much of an issue that you are willing to risk tearing the sheath on the only thing that keeps you (and those that follow) alive?
I once dropped a 40' virgin pit and within 5 secs of reaching the bottom was completely slimed from head to toe (sank into the muck almost to my waist). My Petzl safety almost got me inverted when after 10' it stopped working. My 8 mil prusiks slipped a little bit, but got me out just fine. Seeing as I rarely climb icy ropes, I can not say, but for now I will stick with the prusiks.

A few questions about the above scenario:
1) was the rope completely gooed for its entire length? Please elaborate on rope condition.
2) What model and vintage Petzl ascender were you using
3) What climbing system were you using?

Question #2: In my NCRC L-1, we were taught our rigging by Ken (can't remember his last name) and he seemed to be, like me, a c-o-b who was somewhat distrustful of all these "new fangled gadgets". He used rescue ascenders but sparingly (he liked his prusik knots)(I am sure RAs work just fine). But the one thing he beat into our heads repeatedly was that "You never use anything in a haul system or safety line, that can cut the rope!" And here you are, using something that you acknowledge can cut the rope, as a PCD. When things go wrong in a rescue, you don't have time to set your PCD "properly". It either works like it is supposed to, or people die.

By "cut", do you mean sever, or just damage? What do you mean by "when things go wrong in a rescue" - can you give an example?

What is "cob" - completely ordinary bloke? curmudgeon of blarney? Enquiring minds want to know!

[cob]

A few questions about the above scenario:
1) was the rope completely gooed for its entire length? Please elaborate on rope condition.
2) What model and vintage Petzl ascender were you using
3) What climbing system were you using?

1) The rope was not... just me and all my vert gear.
2) Uhhh.... The standard Petzl SHA? (sorry, don't know model # and name) originally purchased app 20 yrs ago, above incident occured about 8 yrs ago, and even today all but one tooth are still in good shape (spring too) and the one tooth has been slightly filed to remove the "bend" in it.
3) A rope walker modified to a Texas with the knee backed up to my sit harness. (this pit is at the end of a 3000' belly & hands and knee crawl so an economy of vert gear was required. I know, a FROG is better for such situations but I don't have one) The back-up never came into play as I was able to react quickly enuf to catch myself. The teeth of the safety were so gummed up with mud that they could grab nothing. I suppose I could have cleaned them out with my tongue but I chose to grab one of my muddy prusiks instead.

By "cut", do you mean sever, or just damage? What do you mean by "when things go wrong in a rescue" - can you give an example?

By cut... I mean as discussed in this thread (refer to previous posts for "tearing of the sheath" comments)(when I read that I had a vision of a sheath torn, exposing the core on one side for a length of???) As to whether it is "severed" or just "damaged" is beside my point, which is that a "damaged" rope should not be used again. Not even by the guys below you (even tho technically it is still strong enuf). True?

As for the "when things go wrong in a rescue" example: 4 guys pulling on a Z-rig and something gets hung up, who knows what, but such a scenario is the reason for the call from the litter tender of "Stop, stop, why stop?". As it was explained to me, the force multiplication of a 3-1 haul is unbeleivable (I did the math) and the haul team might not even feel a hang up until it is too late and the rope is cut (as by a "regular" gibbs) and then the PCD is suddenly and quite unexpectedly loaded and yanked out of the tenders hand (presuming there is a tender there). (yeah, yeah, I know that this is the reason to limit the # of the haul team, but guano happens) I was involved in a rescue at Lech where we used a Z-rig and there were 7 or 8 guys on the haul team (I was just a mule) but the guys who set it up were "rescue guys" (one was an instructor).

What is "cob" - completely ordinary bloke? curmudgeon of blarney? Enquiring minds want to know!

cob- completely ordinary bloke? Yes!
curmudgeon of blarney? Quite often!
but most times just a "crusty old bstrd" a guy who is somewhat distrustful of all "new-fangled gadgets", after all, "I'm from Missouri, and you'll have to show me."

I am coming at this from a common sensical point of view, one that is reinforced by some training (I am more than aware that a little bit of knowledge is a dangerous thing) and 20+ yrs of experience (during which I have made just about every non-fatal mistake known to cavers). I am most definitely NOT an expert, and do not pretend to be. You obviously have more vert knowledge in your little finger than I have in my entirety. So did Ken. So did Joe Ivy. But then all that knowledge didn't help Joe much, did it?

So Hank, I answered your questions, how about you answer mine? I ask again: Why would one use an ascender, especially in a rescue situation, that has been reported by others (not me, I have never used a tibloc) to damage rope? Especially when a Petzl rep (you) does not refute those statements? Enquiring minds want to know...

most respectfully, tom

[NZcaver]

Question #1: This thread was started concerning using the tibloc as an emergency back-up ascender. It was pointed out that there have been some problems with it tearing the rope if not used properly. As near as I can ascertain from the thread, this is still a problem. Is weight so much of an issue that you are willing to risk tearing the sheath on the only thing that keeps you (and those that follow) alive?

<snip>

Question #2: In my NCRC L-1, we were taught our rigging by Ken (can't remember his last name) and he seemed to be, like me, a c-o-b who was somewhat distrustful of all these "new fangled gadgets". He used rescue ascenders but sparingly (he liked his prusik knots)(I am sure RAs work just fine). But the one thing he beat into our heads repeatedly was that "You never use anything in a haul system or safety line, that can cut the rope!" And here you are, using something that you acknowledge can cut the rope, as a PCD. When things go wrong in a rescue, you don't have time to set your PCD "properly". It either works like it is supposed to, or people die.

Or at least, that is what I was taught. Have things changed that much?

Tom, those are both good questions.

Answer #1 - there really is no perfect answer for you. Yes - when climbing if you don't set the Tibloc properly before applying your weight each time, it could damage the rope sheath. But even then, we're usually talking minor stuff under normal static body weight - not "tearing" the sheath apart or cutting the rope. As previously mentioned, Tiblocs and Prusiks both have their advantages. They are both small and light, but Prusiks are much cheaper and less aggressive - particularly on loose-sheath ropes. But the Tibloc is easier to slide up a rope and can give better grip in adverse conditions. Also it's not likely to slip when you're climbing a loaded rope, like a Prusik can if not carefully set.

Answer #2 - NCRC L-1 focuses mainly on applying wilderness technical rescue standards/practices to the cave environment. That means when your team responds (or you as a caver assist a team) you are using their approved methods - and their equipment, usually. This includes the likes of 11mm main and belay ropes, 50mm bearing pulleys, Rescuecenders and/or 8mm Prusiks, etc - but no Tiblocs! They were NOT designed for this application.

However, when it comes to doing small party self-rescue (aka companion rescue), you probably won't have much of that big bulky kit available - or much in the way of manpower. Using a Tibloc as a PCD for hauling a single-person load (as Petzl show in some of their diagrams) should not be a problem. Remember the HAUL CAM is the MOST critical place to use a device that WON'T cut the rope - not the PCD. This is because if you get a bunch of burly firefighters hauling on a mech adv system and the load hangs up, one big heave and they'll cut the rope - IF they're using a Gibbs or toothed-cam ascender. Generally speaking, your load is not going to take a significant fall on the PCD you're hauling through.

Hence, in a small-scale improvised system, the Tibloc should be fine to use as a PCD or even a haul cam (carefully). As I stated previously, the Tibloc is self-tending when used as a PCD, and doesn't need to be carefully set each time like when used as a personal ascender.

And yes, I know the Ken you mentioned - your description was excellent! I think it's good to have some natural skepticism of new-fangled gadgets, but it also pays to have a willingness to try these and figure out their uses and potential failure modes. Ken is highly adept at all the above.

[NZcaver]

<snip>
As it was explained to me, the force multiplication of a 3-1 haul is unbeleivable (I did the math) and the haul team might not even feel a hang up until it is too late and the rope is cut (as by a "regular" gibbs) and then the PCD is suddenly and quite unexpectedly loaded and yanked out of the tenders hand (presuming there is a tender there).
<snip>

Dude - if your haul cam cuts your rope, there is no load for the PCD to capture!

You're confusing the function of a PCD (which is on the main line) with that of the BELAY - which usually employs tandem triple-wrap Prusiks on a seperate line. This is why you *never* use a Gibbs/toothed ascender as a haul cam on a full "rescue-rated" haul system. That way you won't cut your main and shock load your belay.

[cob]

Tom, those are both good questions.

well, I thought so...

Answer #1 - there really is no perfect answer for you.

there rarely is...

Yes - when climbing if you don't set the Tibloc properly before applying your weight each time, it could damage the rope sheath. But even then, we're usually talking minor stuff under normal static body weight - not "tearing" the sheath apart

as in a "pulling of the sheeth" like what happens with a bent tooth?

As previously mentioned, Tiblocs and Prusiks both have their advantages. They are both small and light, but Prusiks are much cheaper and less aggressive - particularly on loose-sheath ropes.

agreed...

But the Tibloc is easier to slide up a rope and can give better grip in adverse conditions. Also it's not likely to slip when you're climbing a loaded rope, like a Prusik can if not carefully set.

ONLY from personal experience... sliding a prusik up the rope was never that big a deal, and the little bit of slipping I experienced, I did not mind.

This includes the likes of 11mm main and belay ropes, 50mm bearing pulleys, Rescuecenders and/or 8mm Prusiks, etc - but no Tiblocs! They were NOT designed for this application.

this is where you guys lose me: tiblocs weigh no more than 8mm prusik and "They were NOT designed for this application" (your words) so why???

However, when it comes to doing small party self-rescue (aka companion rescue), you probably won't have much of that big bulky kit available - or much in the way of manpower. Using a Tibloc as a PCD for hauling a single-person load (as Petzl show in some of their diagrams) should not be a problem.

Uhhhh... NZ... what is bulky about a couple of 8mm prusik loops?

Remember the HAUL CAM is the MOST critical place to use a device that WON'T cut the rope - not the PCD.

Must most disrespectfully disagree, because if everything else goes to hell in a handbasket the PCD is your last line of defense. I want that bomb proof, and am not going to use a device that "was not designed for this application"

This is because if you get a bunch of burly firefighters hauling on a mech adv system and the load hangs up, one big heave and they'll cut the rope - IF they're using a Gibbs or toothed-cam ascender.

interesting that you and I envisioned the same scenario (tho I had "burly cavers" instead of firefighters)

Generally speaking, your load is not going to take a significant fall on the PCD you're hauling through.

unless the haul system breaks, in which case a tibloc as a PCD is a device "not designed for this application"?

Hence, in a small-scale improvised system, the Tibloc should be fine to use as a PCD or even a haul cam (carefully).

but why when it is "not designed for this application"?

As I stated previously, the Tibloc is self-tending when used as a PCD, and doesn't need to be carefully set each time like when used as a personal ascender.

NZ, most respectfully I must repeat, "I'm from Missouri, and you have to show me." Think about it for a second (never mind Petzl's literature): an ascender that damages a rope when 250 lbs of force is applied to it (unless set just right by the user) will NOT damage the rope when 3000 lbs of force is applied and the ascender is not set by any one???? I am sorry, but that stretches the bounds of incredulity, and I will stick with my prusiks. As imperfect as they are, they will not cut the rope.

And yes, I know the Ken you mentioned - your description was excellent! I think it's good to have some natural skepticism of new-fangled gadgets, but it also pays to have a willingness to try these and figure out their uses and potential failure modes. Ken is highly adept at all the above.

Ken is indeed beautiful. I learned more from him in 3 days, than I had in the 10 yrs previous. As to the 2nd part... I will let others try out these "new fangled gadgets" and when the body parts have been scraped off of the floor, or NOT, as we all hope, then I will, or will not use them, because unlike Ken, I am not adept at "trying these and figuring out their uses and potential failure modes".


tom

[cob]

Dude - if your haul cam cuts your rope, there is no load for the PCD to capture!

Dude, correct me if I am wrong (it has been 10 yrs) but does the PCD go above or below your haul system???

You're confusing the function of a PCD (which is on the main line) with that of the BELAY - .

No I was not, I was just not real clear (my apologies), but your use of the tibloc in a rescue situation, DOES...

This is why you *never* use a Gibbs/toothed ascender as a haul cam on a full "rescue-rated" haul system. That way you won't cut your main and shock load your belay

if it is a rescue... it is a full "rescue rated" haul system, and it either cuts the mustard, or it cuts the rope. Which is it?

And guys, I am asking questions here, based on previous posts including yours, a clear succint answer would be appreciated.

tom

[NZcaver]

Tom - I see how my comments could be confusing to some people.

We are talking 3 DIFFERENT applications for Tiblocs and Prusiks etc here:
1 - Personal ascenders
2 - Small party rescue (ie limited people and gear, and a ONE PERSON load)
3 - Full-scale rescue (often a two person load).

When I quoted bulky gear being used in full scale rescue (and not normally carried caving) I meant the whole system - not specifically those little 8mm Prusiks. What the Tiblocs were NOT designed for was FULL-SCALE rescue hauling - are you with me? To over-simplify even further, one person load - Tibloc usually OK. Two person load - not good.

Again, in a full-scale rescue the PCD is not the last line of defense - the belay is. In fact it would be very unlikely for a PCD to take a shock load. Regarding your "3000lbs of force" comment, in a small party situation you would design your system so forces like this could not be generated. Like using a counterbalance lift, for example.

And by the way - I've also seen incorrectly sized/set Prusiks strip the sheath on a rope when overloaded, so don't sleep too easy...

[NZcaver]

Dude - if your haul cam cuts your rope, there is no load for the PCD to capture!

Dude, correct me if I am wrong (it has been 10 yrs) but does the PCD go above or below your haul system???

You're confusing the function of a PCD (which is on the main line) with that of the BELAY - .

No I was not, I was just not real clear (my apologies), but your use of the tibloc in a rescue situation, DOES...

Oh - OK. Yes the PCD can go below the haul system, but if so it usually needs to be tended. In fact now that I think about it, haul systems are often (usually?) taught this way - good call. Personally, I prefer to have it riding by the first pulley above the haul cam - but your preferences may vary. In the situation you described, yes, the PCD could take a shock load - and therefore a RESCUECENDER is the device best/most commonly used here.

My apologies for misinterpreting what you were saying.

[fuzzy-hair-man]

I think a large part of the reason that the Tibloc SEEMS to work as a PCD(Progress capturing device?) is that the rope its working on is under tension so the rope is straight (so the top teeth are not able to tear into the rope) and also there is no user grabbing onto the carabiner pulling at angles that aren't intended. (Some thoughts not necessarily facts)

cob: When it all goes pear shaped you don't necessarily have the gear you'd like to have (this applies to rescue and a normal trip) so you need to improvise (but safely) in this case you could be very grateful for a couple of backup ascenders.

The reason I am currently preferring Tiblocs to prusik loops is because they should be able to get you out of anywhere, to my mind a backup is not too useful if it only works under some conditions.

A rescue manual I read (I have not been rescue trained and I agree this is probably a case of a little bit of knowledge being dangerous) has said they do not recommend prusiks as a PCD because they do not work in all rope conditions, as a last resort yes. Whilst this same manual does not recommend Tiblocs for the same job (they are not mentioned at all) I thought that they would get over the difficulties of prusik loops.

Additionally this manual shows building a PCD from pulleys (various kinds) and Crolls, Ascensions, and Basics all of which are designed as personal ascending items they are not intended as rescue PCDs but circumstances dictate that they have to be used. These ascenders have a similar rating to the PCDs designed for rescue work so why are they unsuitable ? The Tibloc's rating is similar to other ascenders.
Take the Pro Traxion for example it has a breaking strength of 2.5 kN as a self jamming pulley where as the Tibloc breaks at 12kN. Other ascenders have better breaking strengths.

Maybe the answer is that should we need to use a PCD I substitute my ascenders for Tiblocs and donate my ascenders for use in the rescue rig as these are a more proven solution.

[cob]

but if so it usually needs to be tended. In fact now that I think about it, haul systems are often (usually?) taught this way -

In the situation you described, yes, the PCD could take a shock load - and therefore a RESCUECENDER is the device best/most commonly used here.

My apologies for misinterpreting what you were saying.

Now that we are(hopefully) past the misinterpretations (apologies all around ) we can get back to the educational mode.

#1: It needs to be tended even with a prusik minding pulley?

#2: As I recall.... Ken used his rescuecenders for the haul line (they would slip if too much force was applied?) and prusiks for the PCDs (as I recall, he DID say it was just his thing)

#3: In another post you said you had seen where prusiks had torn the sheath from a rope??? This is news to me (not being sarcastic, seriously, I have never heard that). I thought the main advantage of a prusik was it could NOT damage the rope (in that way at least).


tom

[cob]

cob: When it all goes pear shaped you don't necessarily have the gear you'd like to have (this applies to rescue and a normal trip) so you need to improvise (but safely) in this case you could be very grateful for a couple of backup ascenders.

Which is why I always carry a couple of back-ups (yes, prusiks)

The reason I am currently preferring Tiblocs to prusik loops is because they should be able to get you out of anywhere, to my mind a backup is not too useful if it only works under some conditions.

The reason I still use prusiks is they have always worked in the past for me... this could well be because they are perfectly suited for the conditions I cave in.
I should point out that I am not as "vertical" as I used to be, my vertical work these days is limited to the 20-150' pits we have here in Ozarkistan and that only happens about 6 times /yr. (it is very rare I go to TAG nowadays , and have not been able to manage a Mexico trip in 3 yrs) This is due to the fact that my caving focus has shifted over the years, and all the vert I do now is (mostly) directly related to survey.

A rescue manual I read (I have not been rescue trained and I agree this is probably a case of a little bit of knowledge being dangerous)

only when misapplied, something we ALL need to remind ourselves of, and the opposite can be just as dangerous, lending one to an attitude of complacency.

has said they do not recommend prusiks as a PCD because they do not work in all rope conditions, as a last resort yes.

I return again to the fact that my NCRC was 10 yrs ago, and my "retraining" has been limited at best, and my memory is far from perfect... BUT, I think Ken preferred them. Techniques, I am quite sure, have changed.

The Tibloc's rating is similar to other ascenders.
Take the Pro Traxion for example it has a breaking strength of 2.5 kN as a self jamming pulley where as the Tibloc breaks at 12kN. Other ascenders have better breaking strengths.

The breaking strength of various ascenders is beside the point if the question being asked is "rope damage".

Maybe the answer is that should we need to use a PCD I substitute my ascenders for Tiblocs and donate my ascenders for use in the rescue rig as these are a more proven solution.

As NZ said in an earlier post, the answer is rarely perfect. Some buddies of mine had to do a rescue in Mexico at San Tomas (???) 700' (???). I doubt very much they had it set up to specs, they did the best they could with what they had and got the guy out (I think I was told they had the Z-rig set up in 15 mins).

My point was,
we always have a choice, and that choice is made before we get into the vehicle to go to the cave.
My question was,
why pick something that has been shown to damage the rope (other people posted this, and nobody disputed it. I have no personal experience with the tibloc) especially in a rescue situation?

ANY ascender can damage the rope if misused, but my reading of those posts was that the tibloc was so finnicky that if not set just right it would tear the sheathing on the rope. Then I saw NZs pictures of the tibloc as a PCD... I have been places, as have so many others here, where rescue is not an option. You either deal with whatever situation comes up or... not. In these situations, rope tends to be at a minimum, and a belay is not always an option that is available. Equipment is never perfectly suited, and...

well, why have something that finnicky? It just did not (and still doesn't) seem to make sense. Unless the tibloc is not that finnicky?

tom