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waltereo01
climber
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May 16, 2007 - 07:41pm PT
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Hi,
What those NEW aliens look like ???
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waltereo01
climber
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May 16, 2007 - 08:47pm PT
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Cheap system to test your cams
After reading the different system to test the cams from Boku (http://www.supertopo.com/climbing/thread.html?topic_id=277009&msg=292452#msg292452); and Tim (http://www.rockclimbing.com/cgi-bin/forum/gforum.cgi?post=1591761#1591761);
I use mammut 6 mm perlon (rated at 7.5kn=1 690lb) to pull test
it. If the cam is good, the 6mm perlon will fail first. I finally
come to this system. What you need :
1x vise (20$)
2x car jack (just borrow them)
3x 30cm plumbing steel tube (or just go to a car scrap to pick some steel bar)
10-15m of 6mm perlon (10$)
Total cost around :50$
After 3 cams tested, none failed
Here are the pictures of my cheapo system
The 2 pieces of wood are used to hold the steel bar. Since they
are circular they fall easily. So better to take a flat bar. But
for the top bar, better to take a round one so avoid
concentration of force on the perlon.
The surface if my vise does not provide enough friction. I still try to find a way to add some friction on them.
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BoKu
Trad climber
Douglas Flat, CA
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May 16, 2007 - 09:23pm PT
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> Cheap system to test your cams...
One thing to watch out for is that cam angles in the neighborhood of 15 degrees give the cam something like a 4:1 mechanical advantage - that is, for 1000 lbs of pull force you're applying a 4000 lb opening force on the jaws of the vise. Testing to 1750 lbs yields a 7000 lb opening force.
Vises may look bomber, but so far I've broken two of them doing stuff like that. And when cast iron stuff like that breaks, bits can go flying far and wide.
Thanks, Bob "BoKu" K.
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waltereo01
Trad climber
Montreal, Canada
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May 17, 2007 - 12:09pm PT
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>One thing to watch out for is that cam angles in the neighborhood
>of 15 degrees give the cam something like a 4:1 mechanical
>advantage - that is, for 1000 lbs of pull force you're applying a
>4000 lb opening force on the jaws of the vise. Testing to 1750 lbs
>yields a 7000 lb opening force.
Good to known ! I think mine cost me something like 50-60$ a couple years ago.
Thanks
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Melissa
Gym climber
berkeley, ca
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May 17, 2007 - 12:45pm PT
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Are the crimps in the cables just cosmetic dents in the plastic?
I'd worry that pulling hard enough to put a real fold in the wires would weaken them. That would be the worst...screwing up my cams while testing them to make sure they were safe.
If I took a 1700 lb fall, I'd probably want to give the peice that held me a big kiss and then hang it on the mantle anyway.
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waltereo01
Trad climber
Montreal, Canada
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May 17, 2007 - 01:13pm PT
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> Are the crimps in the cables just cosmetic dents in the plastic?
Yes it is cometic dents. The cable is fine. At 1700lb, the plastic just cannot handle that pressure.
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BoKu
Trad climber
Douglas Flat, CA
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May 17, 2007 - 01:16pm PT
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> Are the crimps in the cables just cosmetic
> dents in the plastic?
>
> I'd worry that pulling hard enough to put a
> really fold in the wires would weaken them.
I wondered about that myself. Definitely a valid concern.
When I did pull tests on the Petrenko Links #3 last year I used a hook that had an edge radius of about 5mm in accordance with UIAA-125.
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Scared Silly
Trad climber
UT
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May 17, 2007 - 01:44pm PT
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Two problems with this testing is that you have now foobared the cable where the test perlon went through. More than likely the cable now has a permanent a crimp in it which you do not want. This has now weaken the cable. And because the cable is covered you can not easily inspect it to see if any of the individual stands have broken which they can do over time.
The proper way to test these would be to have a round jig fitted into the cable loop so that this does not happen.
The other problem is that the perlon breaking strength numbers are the MINIMUM breaking strength. I have seen perlon break at twice its minimum strength when pull tested properly. Further, because you introduced a very small bend into the perlon it may have well broken at below its minimum strength. Knots can often weaked the perlon to as much as 50% (I would have to dig for the exact numbers) So in reality you have no idea what loads the cams were subjected to.
IMHO you just blew three cams ;-).
EDIT: a follow up to this Q&A which shows a huge deficency. This answer is BS. There is no way that you know this as the plastic has not been removed as such not even a simple visual inspection of the cable has been perform. DIY crap like this is how people get themselves killed. And there are things worse than death - like having to drink your beer through a straw and not being able to wipe your own butt.
> Are the crimps in the cables just cosmetic dents in the plastic?
>>Yes it is cometic dents. The cable is fine. At 1700lb, the plastic just cannot handle that pressure.
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Russ Walling
Social climber
Out on the sand.... man.....
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Topic Author's Reply - May 17, 2007 - 01:53pm PT
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Walter: the 6mm to 1600lbs+/- thing is pretty good... did you have any way of testing the actual breaking strength in the testing configuration? Some stuff going on there to skew the numbers, as the small radius of the wire/plastic loop, the actual loop of perlon since I think the 1600lbs is single strand BS, etc.
I'll look around here and see if I have any 6mm and repeat your setup and try to get a number. I'm a bit worried that you might be overtesting the units. Cool test anyway.
Edit: I was typing over ScaredSilly, and have some of the same concerns. Good points SS.
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Ed Hartouni
Trad climber
Livermore, CA
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May 17, 2007 - 02:02pm PT
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if you fall on a cam, and the have the 'biner through the cable loop, do you retire the cam cause you just bent the cable around the 'biner radius?
probably not. Should you?
my guess is that the test can be easily modified so that the pull is no more damaging then "normal" usage.
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Moof
Trad climber
A cube at my soul sucking job in Oregon
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May 17, 2007 - 02:24pm PT
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That alien just looks broken in. My look worse from bounce testing while aiding.
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steelmnkey
climber
Vision man...ya gotta have vision...
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May 17, 2007 - 02:44pm PT
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Perlon way tighter radius than biner. Would think
that would make a difference. I've never "crimped"
a clipin loop in a normal fall like that Alien
from the test looks.
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S Kraft
Trad climber
jacksonville nc
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May 17, 2007 - 02:48pm PT
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Fellow Climbers,
Looking over all the evidence one would conclude that all the cams are suspect at best, I really love these cams and have been using these devices for 14 yrs now. I am going to shift to other trusted brands that I already have on my rack, they have evolved to fit the bill that was once only covered by aliens in the past. This sport is dangerous enough and does not lend too many second chances once the chain of events start to unravel, to have to worry about weather or not your cam is going to explode when you are placing in a spicy spot is something I won’t deal with, I don’t plan to fall but should I fall, how far do I fall?
Steve K
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Charlie D.
Trad climber
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May 17, 2007 - 03:55pm PT
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I know of other individuals who have load tested with similar results. There are distributers who have pulled the product from their inventory. Why is everyone doing CCH work for them?
Obviously their manufacturing has serious quality control issues. This equipment isnt like selling hats where if it falls off your head you just pick it up.
It's time for CCH to answer some questions and take the appropriate action as a responsible manufacture of a life safety product. God knows enough can go wrong without some assistance.
Berg Heil,
Charlie D.
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AbeFrohman
Trad climber
new york, NY
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May 17, 2007 - 04:08pm PT
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does anyone have an idea of CCH's testing methods? what are they doing to complete their tensile testing?
is it worthwhile?
if their gear manufacturing methods are such crap at the point, can i trust their ability to run a test?
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Rock!...oopsie.
Trad climber
pitch above you
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May 17, 2007 - 04:17pm PT
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Abe... great questions. I have no idea on the first 3, but I think I can answer the last one: No.
--->Bob
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healyje
Trad climber
Portland, Oregon
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May 17, 2007 - 05:11pm PT
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"It's time for CCH to answer some questions and take the appropriate action as a responsible manufacture of a life safety product."
That time and opportunity window was a year ago - now that time has past. At this point everyone would be best served if CCH simply shut down or sold out. The process of selling a company, however, is a fairly rigorous financial and legal process that, given basic QC seems to be escaping them, would seem equally beyond their reach.
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Melissa
Gym climber
berkeley, ca
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May 17, 2007 - 05:15pm PT
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That's says something coming from you, healyje, as IIRC, you were really going to bat for them (with them?) acting in good faith fixing stuff before.
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waltereo01
Trad climber
Montreal, Canada
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May 17, 2007 - 05:44pm PT
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@Scared Silly : you are right I don't known if the cable is in good condition. I should use a device to avoid that that crimp in the
cable.
Since I am not a Professional tester/QA/metallurgist, I'm just
doing my best.
Just want to share the way I test them. That's true it is not THE
perfect system. Boku system is far better but I don't have $$$ to
invest in such rig
Cheers,
Edit: BTW, all my cams have been tested by CCH in Dec 2006. But I'am doing this test myself for a peace of mind. BUT now I' thinking of getting something else (C3 or WC, DMM)..
Scared Silly, do you want to buy mine ? ;-)
@Russ : Please come back to us with the value of those 6mm perlon strength.
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Bo Jespersen
Trad climber
Mt. Vernon, Maine
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May 17, 2007 - 07:31pm PT
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This is the response I got today from CCH. After the informative posts these last few days I had to check it out. Seems painless enough and I will sleep better at night. I am sending mine in ASAP! Thanx all!
P>S I have taken a head first whipper on the orange alien and it only smiled when I took a peek at its position, so I guess you could say I am biased....
Dear Bo Jespersen,
you can send your aliens to us for repair, but we will test these aliens, of course.
A price for new wires is $10.00 of each alien, new sling - $ 4.00 of each(including shipping)
Best regards,
Nadia.
-----Original Message
From: bojen@adelphia.net
To: cchaliens@aol.com
Sent: Thu, 17 May 2007 8:08 AM
Subject: gettin' worried
Howdy,
I have been a long time owner of aliens and have trouble thinking of life w/o them! But, as a new dad, I am concerned now. New posts on Supertopo are not encouraging! My cams do not have the dimple and I understand that makes them "safe". But, mine are 5+ yrs old and was wondering if I could get them tested for cable strength and get some new slings sewn on? What am I looking at for cost and turn around time. I own all colors and doubles of everything up to yellow. I have a trip planned in 0ne month, can you make it?
Thanks in advance,
Bo Jespersen
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