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Expansion and strength chart
Designed by Ray Jardine in the early '70's.
His original design had a flexible stem, but he was persuaded
that this would not stress the cams consistently. So the stem was
cast, and the original Wild Country friend was conceived. The
development of the flexible stem was a major step in the SLCD
design.
| The SLCD works by transferring the
downwards fall, sideways into the walls of the crack.
This allows the device to hold in less than perfect,
flared cracks. The cams push into the wall at around
13.75 degrees from horizontal. This number was reached
from a whole load of technical equations, and is used on
all Wild Country cams. Black Diamond use 14 degrees,
which has an unnoticeable difference. No matter how
compressed the cam is the sides always make the same
angle, this is as they are designed on a logarithmic
spiral. The effect is the same as bridging. |
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The axle is the part of the device that
takes the most stress, due to it being pushed from all sides, by
the cams and stem. The most common design is the single axle
which is simple, strong and effective. But does have a couple of
problems. There is not much stopping the cams from slipping and
not staying perpendicular to the axle. Which in a large fall can
be a problem. Also the cams could spin past each other,
inverting. Most devices now come with cam stops that prevent this
from occurring. The other axle design is a twin axle, from Black
Diamond. This has a number of advantages. It naturally stops the
cams inverting and has a larger range of expansion. But it is
slightly heavier.
The stem also has two distinct designs,
single and double. Single stems, rigid or flexible are the
simplest and lightest designs. They load the axle in the centre.
The single stem also allows the trigger to be floating, thus
allowing the cams to be moved with a certain amount of
independence from one another. The solid stem can be vulnerable
when loaded over an edge, so are usually used in wider cracks.
Double stemmed devices have a wire loop that is connected to
either end of the axle. The bracing stops it bending when the
trigger is pulled, but also doesn't allow it to bend vertically,
but this is a very rare occurrence. The triggers tend to last
longer than on single stemmed devices, but do eliminate the
ability to move the cams separately.
As these devices are so complicated, they
require slightly more care. They do need regular oiling and
cleaning. I find WD-40 works very well, and it doesn't seem to
have a detrimental effect on the sling. If see cliff climbing,
they need to be looked at regularly for signs of corrosion,
usually on the springs. If the stem is covered then you simply
have to trust that all is well.
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| HB
Quad Cam They
use a double stem, and have a unique ring pull trigger.
Which can be a bit hard to use with gloves on, but so are
all SLCD's. The trigger also allows the device to be
placed deeper. There are lugs on the cams to prevent the
device inverting. I find the smaller devices are the best
cams available, mostly due to the narrow head.
These are my personal favourites.
This is mainly due to the fact that my biggest falls
always seem to be onto them. On Strpiombante E1 5b, at Frogatt, I fell off the top move. Which is a
long reach from a slopping lay back hold, to another
sloping jug. The gear I landed on was a single Quad Cam
1, placed just up from the bottom of the top crack. I
then took the gear out and climbed it without incident.
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DMM 4CU
(expansion
chart)
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use a double stem, similar to the quad cam. It has cam stops, and an extremely
smooth action. Instead of a ring pull they use a wider bar. It seems that
the natural way to hold it is to have one finger inside the frame and one
either side. This allows the cams to be manipulated a little bit more than
the quad cam. Also there is a couple of small drilled holes in the
trigger. This is for you to thread some cord. So if the cam gets lost deep
in the rock, and you cannot reach the trigger, there is a chance of
retrieval. |
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The cam unit also has an innovative sling arrangement.
The sling is double length, but doubled over. This allows some versatility
with the placement of the cam to reduce rope drag. If all this wasn't
enough it comes with a colour coded karabiner. All this for just £35.
These cam units are destined to become popular.
The 3CU is just like the 4CU just in
smaller sizes and with 3 cams. Thus they are a little lighter, but not
quite the same amount of holding power.
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| Wild Country Technical Friend
(expansion
chart)
These are the latest flexible device from
Wild Country. They have new camstops to stop inverting,
and a plastic cage around the stem to stop the trigger
twisting. The slings are spectra which is very light and
strong. The cams are anodised red to prevent corrosion,
and look different. The largest size 6, is the biggest
cam on the market. The wide head stops the cam wobbling
as much as some. This cam is generally regarded as the
best SLCD.
I have a friend 4 which recently
managed to break its right trigger wire. Due to the
brilliant sales support, Wild Country are going to fix
the wire and replace the sling for around £8 +p&p.
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| Wild Country Forged Friend
(expansion
chart)
The latest incarnation of Jardine's original
design. The stem is now forged, instead of cast, and the
profile is I shaped giving extra lightness, without
reduced strength. Camstops have also been added. Due to
the rigid stem it is not a good idea to load them over an
edge. For some reason the design retains the tie off
hole. Which was designed to tie off the cam, and thus
reduce the moment on the stem.
Recently on an SPA course I was
told that using them is a bad idea, due to this loading
over an edge. But the stem is now so strong that it would
have to be some sort of massive fall to sheer it. I was
told that if I could break it in a fall, then they would
give me another one free. That was West Coast in Fort
William. I think the larger sizes are very useful,
anything below the size 3, I would consider slightly
dodgy. But due to the small price tag I think they are a
worthy extension to anyone's rack.
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Black
Diamond Camalots (expansion
chart)
These are the coolest looking cams around,
with their innovative twin axle design. The smaller designs sadly
cannot accommodate the two axles, so single axles have been
utilised. On the single axle versions camstops are added to
compensate, and their head widths have been reduced dramatically,
as most placements in this size tend to be narrow. They have also
added a ring that stops the trigger being pushed up into the
cams, this protects the wire. It is a pity that they are so
heavy, and expensive otherwise I would have more. Having said
that they have brought the price down a bit recently. One qualm
is that the stem is covered, thus not allowing any damage to be
seen. I find the most useful size to be Camalot 2. It is almost
the same size as the forged friend 3, but compresses a lot more.
| Vectors These are budget cams, made by Clog. They
look similar to HB flexi-fits, but are a cut down
version. They have no camstops and quite dodgy looking
machining on the cams. They have a covered stem again,
and a regular sling. I am not totally convinced with
these bits of equipment yet. But if you are looking for a
cheap way to extend you rack, then these fit the bill. They cost around
£20.
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Courtesy of UKCrags.com |
Fancy some cheap gear. A
quick holiday, Beer at 15 pence a pint, Yep 15 pence a pint. Well you need
a trip to the Czech Republic, maybe "Prague" or "Bruno" that will do. Ahh
and yes there is some rock there to make it even more worth while. Lets
start with some cams. Fed up with paying 20 to 40 quid for good flexi
cams, a quick flight to Prague which is about £100 on el cheapo flights
can reap high rewards. Rock Empire, not a name that inspires confidence,
do a nice range of Flexi cams which when seen with your own eyes give you
a sense of well being. At about 300 to 700 Crowns each depending on size,
by the way there is about 45 Crown is the pound, it makes sense to fill
your suitcase. All cams have UIAA CE 0123 stamped on them and declare
14KN or 11 KN for the smaller (Czech size 1) cams. The only strange thing
I have noticed is the tape is looped, you can just see that in the photo's
but it did not cause any problems in action. Oh and yes they work, I prove
it every time I go climbing. Buy a whole rack for a few quid.
Verdict:- Good
value. |
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