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Post by fwdixon on Dec 18, 2006 13:21:56 GMT -5
I have heard a lot of information regarding the use of figure-8's, Petzl Stops, and rack for vertical descents. I think an 8 will serve my purpose, but i was also considering a Petzl I'D due to it's ease of use and attachment to the rope. I am a Marine Repair technician and routinely have to climb up masts to perfom work. I use a pair of Petzl Ascesions for this, but repelling with them is a pain. Heights above 100' are rare but not enitirely uncommon. Most climbs are in the 40-60' range. Any feedback would be helpful.
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Post by Rebel Rouser on Dec 18, 2006 18:40:58 GMT -5
A figure 8 may do the trick but you might want to stay away from static lines and use a dynamic rope with it. Figure 8 does not like stiff static ropes. I use a stop descender for shorter static line drops and to have automatic stopping ability.(no need to lock off) Sounds like a rack would be a bit much for what you want to do. The rack is definitely the most sophisticated of the devices mentioned. I'm going to state the obvious and say get proper instruction with any descending device. I'll bet it is hard to rappel with a petzl ascender!  Kent |
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NZcaver
Beginner
U.S. Caver
Posts: 140
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Post by NZcaver on Dec 19, 2006 3:24:09 GMT -5
Arguably, the Petzl I'D is actually the most sophisticated of the devices you mentioned - and probably the best for your intended purpose. Here's why. The I'D is essentially a double-action stop descender that you can also use as an autolocking belay device. And unlike most descenders, it's really easy to back-feed the rope through for work-positioning situations. As Kent already stated, your Petzl ascenders were not designed as rappel devices! However, the I'D can be used safely (and relatively easily) as an ascender, in conjunction with your other ascender. This makes it very easy to move up and down without doing a traditional changeover. You won't find many cavers out there who use - or have even tried - the I'D. Between the sealed clutch mechanism (which may not like being filled with gritty cave mud) and the high cost (US$180), there isn't much call for them underground. But for industrial cleaners, maintenance technicians, and some rescue workers, these are the bomb. To check the specs, go to www.petzl.com and search for I'D (D20). There are PDF instructions you can download. [Coincidentally, I have a spare I'D for 10-11.5mm rope - brand new in the box. If you are interested in one for a bit cheaper then retail, PM me.] |
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Post by Tim White on Dec 19, 2006 11:48:34 GMT -5
Another option is the Petzl GRIGRI®, a Self-braking belay device and descender. Used with an ascender, one can quickly ascend rope, lock off in a position for work and descend. This technique is used world over by rope access workers.
The gri-gri at $79.95, is a LOT cheaper then the I'D.
PM me if you have any questions.
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Post by Rebel Rouser on Dec 19, 2006 13:02:58 GMT -5
When I say 'sophisticated" I'm referring to complexity in operation. I am not very familiar with the petzl ID but it is probably very similar to the grigri in function. The most difficulty is in proper threading of rope through device. I guess you could use the ID or a grigri for ascension but I would think a couple of handled ascenders would be much faster and easier to use. IMHO the rack is the most complicated to use. Kent
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NZcaver
Beginner
U.S. Caver
Posts: 140
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Post by NZcaver on Dec 19, 2006 20:40:29 GMT -5
When I say 'sophisticated" I'm referring to complexity in operation. I am not very familiar with the petzl ID but it is probably very similar to the grigri in function. The most difficulty is in proper threading of rope through device. I guess you could use the ID or a grigri for ascension but I would think a couple of handled ascenders would be much faster and easier to use. IMHO the rack is the most complicated to use. Kent Yes, using a pair of ascenders in the "proper" manner should certainly be faster/easier than using one ascender and back-feeding the descender. I suggest doing the main climb on 2 ascenders. Then by changing over to an I'D, one can easily rappel or climb to reposition oneself as necessary while working - without doing further changeovers or having to down-Prusik on a pair of ascenders. The GriGri is indeed much cheaper, and a little smaller, than the I'D. It is somewhat similar in function, but the I'D has a double stop action (which takes some getting used to) and to my knowledge is the only descender that can be fully locked off safely without doing an actual rope tie-off. This may not matter to some users, but the I'D is also rated for industrial use - including occasional use with a 2-person load - whereas the GriGri is not. In the context of descenders, I took your term "sophisticated" to mean a device which has more mechanical intricacies/conveniences rather than one that is simply more complicated to operate. The latter does describe your standard rack, which explains why one may not be ideal for our Marine Repair technician given the work he has to concentrate on doing while on rope. |
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