Taken from the Black Diamond QC Archives. More interesting articles can be found at - http://www.blackdiamondequipment.com/en-us/journal/climb/all/qc-with-kp-from-the-archives-1
August 16, 2006 - Breaking Fixed Draws and Biners from a Dark, Dreary Cave Route
Lately I've had some people wondering how strong their old gear
is-stuff that's usually been fixed on some 'proj' for some unknown
amount of time-and rather than leaving it up indefinitely for some
unsuspecting sucker to take the big ride, they remove it and if/when I
get around to it we'll break it to see if we can learn anything.
Recently someone stripped their old gear off the route
Burning
in the Hell Cave at American Fork, Utah. Now talk about a hole. That
place sees more seapage, water, cold and dark than you could imagine,
but even still does manage to see some sunlight. These were classic
beat-up looking draws. Super crusty webbing, corrosion and oxidation on
the biners, the full meal deal...
My guess is as usual: the biners are much stronger than
you would think given how they look, but the webbing which appeared to
be dried up and even somewhat brittle was my concern.
Remember:
- The CE requirement for new slings is 22 kN
- Biners such as these must maintain 20 kN in closed gate, though all of these were rated stronger (22-26 kN)
- Typical sport falls are in the 2-5 kN range...
- We tested these in the tensile testing machine AS quickdraws-then
after the webbing was broke, we tested the biners individually.
The Results
The biners all met their rated strength. It's nice to know that in
most cases even old beat-up looking biners that have been left outside
for months are still burly strong. The risk with these usually isn't the
strength of the biner in closed gate, rather: sharp edges of worn
biners causing a rope to cut (corroded, oxidized biners having such
crappy gate action that the gate won't close). I know, I've climbed on
draws with 'fixed' routes at Rifle, the VRG, the RED, Maple, etc and you
clip your rope in then have to manually close the gate... not sweet.
All of the webbing failed to meet 22 kN. The range was as low as 13 kN and as high as 20 kN (the average value was 17.6 kN).
Conclusion
Though not dangerously weak, the nylon webbing from these quickdraws
was definitely weaker than when new due to exposure to the elements,
use, wear, etc. The biners were all still burly in closed-gate testing.
The problem with mank gear like this is ensuring that the gate is
closed... more on this in a later installment.
Moral of the Story
Now people have been climbing on these exact draws for who knows how
long, without incident-and chances are they could have stayed up there
for much longer and been fine, but you must use your common sense and
don't climb on fixed gear that you think is suspect, and don't leave
suspect gear on routes-you're not doing anyone any favors. Don't be shy
to replace old crappy gear-it may cost you a bit, but it's good karma,
plus you'll be doing yourself a favor on that redpoint burn-the last
thing you want to be thinking is "I sure hope that old manky quickdraw
at the crux is still strong enough in case I whip..."
Out for now,
KP
