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Ascenders are very useful devices, they are
basically uni-directional rope clamps. Locking in one direction,
while sliding easily in the other. Ascenders are mainly useful
when situations arise that were not intended. Such as the second
falls off the overhanging and is hanging free in space, thus the
rope has to be climbed to regain the rock. Or one climber gets
hit by a falling block and is knocked unconscious, then they will
need to be hoisted up, or the other climber will need to escape
the system. In all these situations an ascender would be
invaluable.
The ascenders mentioned below are not
really designed for usage like a handled ascender. For instance
they are not designed for long fixed rope ascents or caving. The
problem being that they would become uncomfortable to hold over
an extended period. They are also more likely to be dropped.
All devices are super strong, so this is
not the limiting factor to the weight they hold. the limiting
factor usually comes down to the strength of the rope. Most
devices use a camming system, to change the downwards pull into a
pinching force. So as the loading increases, the rope can get
damaged and can even completely fail.
Prussik loops were the original method of
ascending a fixed rope. 5mm prussik loops tend to work best.
Autobloc
(French prussik)
This is simply when the prussik loop is
passed round the rope and the ends are clipped together. The
number of times it goes round the rope, varies the friction and
holding power. It can be used as an ascender but is not generally
used as such. This is because it doesn't lock solid. But it is
good as a safety backup for an abseil, by clipping it to a leg
loop. So if you get something caught in the abseil device or you
simply let go of the rope, you do not go anywhere. This can be tied with slings
as well, the friction is just as good.
Prussik
This is the original ascending knot. Which
is simply a double or triple larks foot round the rope. The
number of times it goes round the rope varies the friction. It is
a little difficult to use as it can lock very tight, and is thus
difficult to move in either direction. But it is strong,
reliable, light and cheap. If it is only for emergency situations
than it is very good. But it would be impossible on longer
ascents.
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Petzl
Tibloc :
39g, 8-11mm This is the
simplest ascender ever devised, as it has no moving
parts. It looks a little weak but it really isn't, also
it is only a little heavier than prussik loops. It is not
good as an abseil protector, as the teeth are fairly
aggressive, and would badly pick the sheath. But as
ascending goes it is very good, but does tend to pick the
sheath, but thus does not squash the core as badly as
camming ascenders. At over £12 it does seem to be a
little expensive.
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Wild
Country Ropeman MKI
:
62g. 10-11mm This was one
of the first micro ascenders, and now has two versions,
the MK1 and MK2. The MK2 has a slightly redesigned cam
with conical pins which allows it to work with smaller
rope diameters. The Mk1 runs up the rope smoother than
any other device I have used, and as thus is quite good
for abseil protection. The cam is apparently the least
rope friendly, but is by far the most sheath friendly,
due to the large teeth. I think it is the best micro
ascender available, although the price seems a little
high at over £18.
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