The Petzl Rig - up close!

X...OSHA won't approve anything.

And...yes...nothing but the Uni for all work for over six years. Before that I spent a lot of time using hitches for ascending and working the whole tree on SRT.

ITCC is another issue. Two years ago I used the Uni for all of the Geezers. I think that might have been the first comp climbed on the Uni.

My frustration with having the TCC/ITCC be in any sort of approval status of mechanicals is that they don't seem to apply the same level of concern for all of the various hitch/rope configurations. The body of lab/dyno testing of mechanicals is much more robust and repeatable than many hitch/cord systems. I'm not saying that anyone should be able to come in with a mechanical configuration and not be critiqued, just apply the same level of scrutiny to all of the rest of the gear. For years I've seen GriGris used on half inch arbo rope. Check the cheekplates...the rope is too big! But that's been allowed...that is inconsistent.

In Johno's video he climbs in a system similar to what I came up with awhile ago. I have my Uni attached to my short bridge on the TreeFlex. Keeping the Uni on a short tether or bridge keeps slop and slack out of the system. It also makes it easier to use the neck bungee as a slack tender.

There are so many combinations and permutations of gear. In the end they fall into the 4/5 catagories that cavers came up with in the '60s.
 
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[ QUOTE ]
A Grigri, Cinch, I'D, Rig, shelled ascenders, toothed cam ascenders, and I dare say, the Unicender are not fall protection gear....Have there been any tests with the Unicender to determine how it catches a fall?

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It may not be rated for fall protection, but this is pretty impressive.

http://www.youtube.com/watch?v=5Nt0poDinJk


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Would you really want to fall that far? It would be most interesting to rerun the test with a limb about 5 or 6 feet below the load. I sure don't want synthesize situations, but we are in trees, trees have limbs and stubs. I'd expect we wouldn't want to hit one.

Further I wouldn't want to fall like that and feel that sharp pain when my back snapped because I wasn't wearing a fall arrest harness.

But the point being, the Unicender is not fall protection. Hitches would probably make for some impressive fall catches too, but again, it's the use of something for fall protection that isn't fall protection.

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I hesitate to bring up any slight deficiency of the Unicender because historically it has been defended passionately as if it were the only tool a man with any sense would use.

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LOL Smart AND wise, I'm impressed.
grin.gif


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LOL! Mostly scared!

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...I am still learning what the Uni is and is not capable of. It can accomplish a lot. There is also room for improvement in the design.

Dave

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Of course it's capable of a lot. I'll have one in a few days - I'm really eager to do all these new things that I've never been able to do before and use only half the energy doing it.
tongue.gif
 
[ QUOTE ]
Of course it's capable of a lot. I'll have one in a few days - I'm really eager to do all these new things that I've never been able to do before and use only half the energy doing it.


[/ QUOTE ]

I hope you get some footage. I'm eager to see more.
 
[ QUOTE ]
Would you really want to fall that far?

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Heck no.

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Further I wouldn't want to fall like that and feel that sharp pain when my back snapped because I wasn't wearing a fall arrest harness.

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Can you calculate the energy absorbed by 5 feet of deceleration added to (?) feet of rope stretch?

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But the point being, the Unicender is not fall protection.

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Still true, but if the unexpected happened and you did fall wouldn't a decelerating, non-rope destroying ascender be preferred?

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I'll have one in a few days - I'm really eager to do all these new things that I've never been able to do before and use only half the energy doing it.
tongue.gif


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Wow, I hope that's not my fault.
blush.gif


Dave
 
Dave,
Sure, we'd like some degree of fall arresting IF we fall, but at the same time we don't want to give ourselves a false impression of security. What we really want is our existing gear to provide fall protection and it just doesn't.

My reaction after seeing the video is that it proves a Unicender is not fall protection. A Petzl Shunt will do a much better job at arresting a fall:

http://www.youtube.com/watch?v=Jv-YCRb6xbI

And it's not fall protection either, but look at what a superb job it does.

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Can you calculate the energy absorbed by 5 feet of deceleration added to (?) feet of rope stretch?

[/ QUOTE ]
Yes.

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Wow, I hope that's not my fault.
blush.gif


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LOL! No, it's not your fault, but I still reserve the right to blame you if this doesn't work out.
tongue.gif


I'm not buying one, one is being briefly loaned to me.
 
[ QUOTE ]
[ QUOTE ]
Of course it's capable of a lot. I'll have one in a few days - I'm really eager to do all these new things that I've never been able to do before and use only half the energy doing it.


[/ QUOTE ]

I hope you get some footage. I'm eager to see more.

[/ QUOTE ]
I'll get footage - you can count on that.
 
[ QUOTE ]
My reaction after seeing the video is that it proves a Unicender is not fall protection. A Petzl Shunt will do a much better job at arresting a fall:

http://www.youtube.com/watch?v=Jv-YCRb6xbI

And it's not fall protection either, but look at what a superb job it does.

[/ QUOTE ]

Good stuff Ron. I have not used the Shunt it looks good. Do you use one? I know Tom does on occasion.

Dave
 
Dave,
Just so you'll know, I enjoy discussing these topics with you. We see things alike, we're just each focusing on a different system of climbing and explaining the potential of each - how could it possibly get any better than that!!!

I don't use a Shunt. I kinda like it, but I have mixed feelings about it. While it looked good in the video I linked, it has been reported that under shock loading, the shell can distort and spit the rope out.
shocked.gif
Another report indicated the eye broke, and it is a marginal eye if you ask me, esp. compared to a micro or Rescuecender. But in Dr. Merchant's book, he recommends the Shunt for the termination of lines that might experience high tension. The idea is that the Shunt will slip at stresses much lower than the breaking point of the rope and hence has a built in safety. As I recall though the tail of the rope is also terminated in case the Shunt broke, but moreso I think to keep the tail of the rope from pulling completely through the Shunt - that wouldn't be good either.

But, Bruce Smith of On Rope 1 says there should be no hardware or knots on a rope that experiences high tension, e.g. a high line. He uses two, three wrap pursiks to terminate the rope on one end (high line) and a high tension tie off (multiple wraps of rope around a tree and a terminating hitch or knot) on the other end. No hardware!

Honestly though, I like the Shunt, and in practice I've never heard of a failure, and I do like the way it handles shock loading in the video. And just for the record, I have zero confirmation that the reports of the Shunt body distorting or the eye breaking are factual.
 
My use of the Shunt is not for load bearing. As the upper ascender in a RADS it should never be loaded anyway. I know...there is a moment when there's a bit of slack though. :)
 
[ QUOTE ]
My use of the Shunt is not for load bearing. As the upper ascender in a RADS it should never be loaded anyway. I know...there is a moment when there's a bit of slack though. :)

[/ QUOTE ]
Still, load bearing is the intent of the Shunt, from the Petzl website:

SHUNT
Back-up rope clamp

Used below the rappel device, the SHUNT works as a rappel back-up and replaces self-jamming knots like the Prusik. Works on single and double ropes.

Easy to install on the rope
Smooth clamping surfaces won't damage rope
May be used to ascend single or doubled rope.

Every time I read that it makes me think I should be using it.
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Of course reading the details, it says "Used below the rappel device..." in that position, it would have some benefit of the rappeling device sharing the load.

I've used the Shunt as described and it works really, really well. One of the good things is after it catches you, you can restart it without having to unload it, IIRC.
 
My rig ran 16 strand for about a year every day. Now it is super smooth on half inch, but it slips on 11.5.
My buddy backed into my truck and offered it as compensation. I use it for things occasionally.
 
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