Changeover questions

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Changeover questions

Postby GroundquestMSA » May 10, 2011 3:10 pm

I've been practicing changeovers in my poor little maple and have a few questions. Firstly, is their any reason I should avoid using a figure 8? I use a rescue 8 because I'm a scrawny lad and have never had trouble controlling my rate of descent. It seems like less bulk than a rack and is quicker to change. Also, my j-rack is a SMC with 6 stainless u-bars but has no tie off bar or whatever those things are called. Is their a standard method of locking off in this case? I have been simply mashing the bars up, pulling up rope from below and tying a quick knot above the rack. I can then stick a carabiner through the knot loop and top of the rack to ensure that I can't budge but this has so far seemed unnecessary. Please remember that I have no knowledge of the vernacular of vertical exploration. Thanks
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Re: Changeover questions

Postby Scott McCrea » May 10, 2011 3:47 pm

Good job. Practicing is the good habit. Asking questions might even be better. :clap:

Nothing wrong with a Fig 8. Smaller and lighter (and cheaper) is a good thing. It is not appropriate for everything, but it is perfect for some stuff. When you get on some really muddy ropes with a fig 8, you'll wish you had more meat on your bones.

When locking off without a hyperbar, simply flip the rope over the top of the rack between the rope and the rack. Then, back under and tie a knot above. This holds the bars together a bit more securely than the method you described.

Changeovers are vertical cavers reserve parachute. Everyone should be very good at them. Kudos for practicing them.
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Re: Changeover questions

Postby Carl Amundson » May 10, 2011 5:27 pm

Figure 8’s are good, cheap & easy to use. I generally have a couple of issues with them.
When you do a changeover you have to remove it from your harness to get it on or off the rope. If you drop it, it’s a problem.
The other is that it twists the rope.

The method Scott described for locking off a rack without a hyperbar is spot on.

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Re: Changeover questions

Postby ian mckenzie » May 11, 2011 11:48 pm

I feel that I should reinforce the shortcomings of the Figure 8 that have already been mentioned. It is very easy to drop, whereas other devices are specifically designed to be operated without having to detach them from your harness. If you drop an aluminum device from a significant height, then you should throw it away. Aluminum 8s also wear out relatively quickly. The twisting of the rope that they impart will cause a subsequent ascending caver to spin on the rope. I know of no serious alpine caver who uses a figure eight, although I can only speak for my region (we do other funny stuff here, like not wearing blue jeans or using carbide lamps) with one exception - cavers who use bobbins will sometimes carry a figure eight for doubled-rope pulldown trips where there is no ascent to get 'spun' on, although the rope-twisting can be problematic when pulling down the rope.
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Re: Changeover questions

Postby NZcaver » May 12, 2011 12:29 am

ian mckenzie wrote:I feel that I should reinforce the shortcomings of the Figure 8 that have already been mentioned. It is very easy to drop, whereas other devices are specifically designed to be operated without having to detach them from your harness.

As Ian and others have said, a figure 8 has a few issues which can make it less than ideal for many caving situations - with the possible exception of small nuisance drops and double-rope pull-downs.

However there is a standard technique for rigging/de-rigging the figure 8 descender which virtually eliminates the possibility of completely dropping it. Clip into the big hole and thread the rope through and over the bridge before unclipping, flipping and re-clipping. This keeps the descender attached to either your harness or the rope at all times. Everybody who uses a figure 8 should practice this technique.

Still, the twisting of the rope, lack of friction options and slightly awkward lock-offs makes the 8 better for rock climbing and perhaps occasional short-drop use in caves, if at all. But it is cheap. :big grin:
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Re: Changeover questions

Postby Extremeophile » May 12, 2011 8:12 am

The Petzl Pirana seems to address most of the listed concerns with a traditional figure 8. It can't be dropped, has multiple rigging orientations to adjust for friction, additional friction can be easily added or removed while on rope, it can be easily locked off, and in my experience it doesn't twist the rope. I suppose some would argue that the device might heat up more resulting in some risk of glazing the rope, but I suspect this fear is more theoretical. I've done 300' canyoneering rappels and it has performed very well. I guess my main concern for caving is that a muddy rope might quickly cut through the soft aluminum shortening the life of the device. Are there other concerns I'm missing?

I like the simplicity, light weight and lack of moving parts. It's expensive for an 8, but cheap compared to a rack or Stop.
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Re: Changeover questions

Postby trogman » May 12, 2011 9:08 am

Extremeophile wrote:The Petzl Pirana seems to address most of the listed concerns with a traditional figure 8. It can't be dropped, has multiple rigging orientations to adjust for friction, additional friction can be easily added or removed while on rope, it can be easily locked off, and in my experience it doesn't twist the rope. I suppose some would argue that the device might heat up more resulting in some risk of glazing the rope, but I suspect this fear is more theoretical. I've done 300' canyoneering rappels and it has performed very well. I guess my main concern for caving is that a muddy rope might quickly cut through the soft aluminum shortening the life of the device. Are there other concerns I'm missing?

I like the simplicity, light weight and lack of moving parts. It's expensive for an 8, but cheap compared to a rack or Stop.


I have a Pirana that I carry ridgewalking with me, and I like all of the qualities you mentioned above. I have noticed, however, that it doesn't work really well on larger diameter (11 mm) ropes. It is great on smaller ones, though.

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Re: Changeover questions

Postby Jeff Bartlett » Jun 15, 2011 3:53 pm

I once tried to come up with 8 reasons that Figure 8s aren't the best choice for caving. I could only come up with 7:

    1. Must be detached from harness to be installed on the rope. Potential safety issue, or you could accidentally drop it. Obvious complication for changeovers and other rope maneuvers.
    2. No half-lock, and full lock is awkward/slow.
    3. Badly twists the rope; this is a minor nuisance in free drops and a semi-major problem if there is a rebelay somewhere.
    4. Friction isn't adjustable, and you can't "dial in" that friction at the top of a pitch.
    5. Eights without "ears" can invert into a girth hitch, a situation where you're stuck until you change over, and hopefully you're not stuck in a waterfall or a constriction.
    6. Aluminum eights wear very, very quickly on muddy or gritty rope, forming sharp edges and/or getting dangerously thin.
    7. Intended for use on flexible, dynamic climbing rope and not stiff, static caving rope.

That said, plenty of people use them and seem to be reasonably satisfied. You won't catch me trying it.
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Re: Changeover questions

Postby Extremeophile » Jun 15, 2011 4:55 pm

Jeff Bartlett wrote:I once tried to come up with 8 reasons that Figure 8s aren't the best choice for caving. I could only come up with 7:

    1. Must be detached from harness to be installed on the rope. Potential safety issue, or you could accidentally drop it. Obvious complication for changeovers and other rope maneuvers.
    2. No half-lock, and full lock is awkward/slow.
    3. Badly twists the rope; this is a minor nuisance in free drops and a semi-major problem if there is a rebelay somewhere.
    4. Friction isn't adjustable, and you can't "dial in" that friction at the top of a pitch.
    5. Eights without "ears" can invert into a girth hitch, a situation where you're stuck until you change over, and hopefully you're not stuck in a waterfall or a constriction.
    6. Aluminum eights wear very, very quickly on muddy or gritty rope, forming sharp edges and/or getting dangerously thin.
    7. Intended for use on flexible, dynamic climbing rope and not stiff, static caving rope.

That said, plenty of people use them and seem to be reasonably satisfied. You won't catch me trying it.

I think only #6 applies to the Pirana. Note - I'm not advocating this to replace racks in all cases. I do think it may be suitable for wet pull-downs or trips with short rappels in remote areas where weight and bulk need to be minimized.
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Re: Changeover questions

Postby Marduke » Jun 15, 2011 8:20 pm

I would still rather munter over an 8 any day of the week.
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Re: Changeover questions

Postby rlboyce » Jun 16, 2011 11:27 am

I've never used a traditional rack, but I see in Alpine Caving Techniques that a braking carabiner is sometimes used to lock off if a hyperbar is not present. Is this still an acceptable practice? Is it quicker to use a braking carabiner or use a knot like described previously in this topic?
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