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michaellane
climber
Spokane, WA
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Do I have to pay DMT/LEB's tab too?
Nah ... let's get him/her to pay!
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Will Eccleston
Trad climber
Atlanta, GA
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Quote from above "I still wouldn't kick it off my rack for eating cookies but no way I'm wiping onto one."
Why would you carry a cam that you weren't willing to take a HARD fall on? (Unless you were aid climbing)?
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the Fet
Knackered climber
A bivy sack in the secret campground
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Disclaimer: I've played with a link cam but haven't climbed with any.
My impression was that the cams on either side of the stem don't act very indepedently. So the cams retract the same amount on both sides when you pull the trigger. This is fine in parralel cracks, but in flares (where a hybrid works good) they would only grab on two lobes on one side. Perhaps this puts more force on one side of the cams causing uneven force to the cam lobes when placed in a flair.
I think they'd be great for Indian Creek, where you'd want a bunch of the same size cams for a parralel splitter crack. With the added range they'd work good for more than one crack width. But for Yosemite where there are so many pin scars and other flared placements I don't think they'd be so good.
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handsome B
Gym climber
SL,UT
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The link cams are awesome for going light and fast while french-freeing.
Plug and go, always bomber.
Gear breaks, plan accordingly.
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Crimpergirl
Social climber
St. Looney
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I met Michael Lane at Red Rocks last March. While he is clearly a hottie and quite nice, he just didn't strike me as Dirtineye's type. NTTIAWWT
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Chiloe
Trad climber
Lee, NH
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I've never fallen with out knowing I was gonna fall.
Damn, I sure have.
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bluering
Trad climber
Santa Clara, Ca.
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Maybe the metal alloy was imported from China...
Craftsman cutters made in China. I only buy German, Japanese, or American tools now.
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Nefarius
Big Wall climber
Fresno, CA
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Michael Lane -
BadAss! Thanks for sharing the history of your company and it's use of the DOJ's PIEP!! I think it's awesome what you guys were/are doing, the reasons for doing it, etc. It is infinitely cool that you guys are still employing some of those folks after their incarceration is over. Super cool!
Cheers!
--rw
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Dick_Lugar
Trad climber
Indiana
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Planes crashes and cams break...what a concept!
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dirtineye
Trad climber
the south
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Maldaly,
I wonder if you (or anyone else) will run a test like that where the cam stem is 90 degrees to the rock face, with the lobes in a vertical crack, fully link cammed out?
That's interesting about when the cam breaks. Possibly if it broke under compression you might not see that til the cam was free of the crack and the pieces can fall apart in an obvious way? Just a guess.
I have to be happy that your test backs up my long standing (and seemingly obvious) notion that cams placed so that lobes are under rotational forces where one side of lobes moves about the other as the stem is levered in a fall is bad. Since one set of lobes is moving away from the fall vector (up), the axle and the fixed lobe is taking a beating, and your test seems to support this
Michaellane, Good idea about DMT/LEB paying. With two personalities they probably have twice as much money to spend, or at least they think they do.
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dirtineye
Trad climber
the south
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shameless bump indeed.
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maldaly
Trad climber
Boulder, CO
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Shame on you, dirt. My tests came from being out in the field and seeing way too many people stuff cams in bottoming cracks so they were prevented from rotating to line up with the force of the fall. My fixture won't allow me to test at exactly 90° but I can come close with cams less than 2".
What I didn't mention about my tests is that every cam was ruined way before it failed. In other words, even at low loads--the kind you see in falls every day--you're likely to trash your cam if you place it in a manner that prevents it from lining up with the forces of a fall. Strangely enough the classic stem-over-the-edge situation rarely trashed single stem cams. Almost always trashed u-frame cams due the the nature of the standing rigging wire they use for the frames. It kinks.
Climb safe,
Mal
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dirtineye
Trad climber
the south
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Yes, yes, Mal, preach it baby!
Thanks for including that bit about bottoming cracks. I'm agin 'em.
But I'd still like to know about the 90 degree thing where the cam can rotate, especially in a high fall factor situation, which must place nearly all the action on the side that is bearing the business as the upward moving side is going the wrong way.
I've always tried to get people to place cams in line with the fall, but all you get is looks of disbelief, and what you usually see is a quick draw on a cam that has either been placed at 90 degrees or rotated that way from rope dragage.
That the link cam, once placed out of line with the fall, can't even rotate, is what worries me about them.
Shame me some more if you got more to tell, by all means!
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maldaly
Trad climber
Boulder, CO
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dirt,
If the cam can rotate into the line of the pull (along with the force) there should be no bad repercussions. It's when the cam can't rotate that weirdness happens. Like you, I'm always astonished when climbers stuff cams in without aligning them to the expected direction of pull. When you place a cam lined up correctly and sling it so it won't rotate as you move by, you will have a reasonably good idea of what it will do when it has to carry a load. If, on the other hand, you stuff in a cam and assume it will rotate to align correctly when you load it, you never have any idea what's really going to happen. This holds especially true with tiny cams. They just don't have the expansion range to adapt to crack changes.
mal
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dirtineye
Trad climber
the south
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besides the chance for rotating cams to walk in or out, there still is an issue that I really don't think can be OK all the time.
when a cam rotates under a load, two lobes go up, and two pivot. The two that pivot are essentially fixed as the rotational point for the two that are moving up. these two fixed ones cant be moving down, or the cam would be falling out. so they are pivoting, which is not something they are designed for.
The two that pivot are at least going to get ground flat a little bit, and maybe twisted a little too, but maybe not so much that you'd notice.
the two lobes that pivot must be bearing the brunt of the fall. The axle must be strained. if some little rock feature stops the pivoting lobes from pivoting, then I guess that's real trouble, like you said.
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maldaly
Trad climber
Boulder, CO
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dirt, we don't see much evidence of damage when a cam that is free to rotate takes a big load. I think that in most cases the rotation happens before the main load hits. I've never seen any deformations on a cam lobe which have indications of twisting. I see diagonal scoring marks all the time but nothing that has a twisting component.
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dirtineye
Trad climber
the south
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well the diagonal marks back up my idea, I guess as you say it just usually doesn't amount to much until the cam can't rotate.
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foot slipped on lichen while laybacking a vertical, smooth-sided corner on one of Rumney's few trad routes;
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