In theory and in most of the time in practice a cam will either pull at very light loads ie a tug with your hand. Or hold until the rock or cam breaks.

In theory and in most of the time in practice a cam will either pull at very light loads ie a tug with your hand.

In theory, perhaps, but in practice, this couldn't be more wrong. Tons of placements look anywhere from bomber to scary-as-fuck, and will hold more than a hard tug, but less than full strength.

GO

And this is due almost entirely to the coefficient of friction changing following the destruction of the rock's surface when the cam is loaded.

Patto is not wrong, its just that confirmation bias and a complex reality tend to obscure the theory he's pointing out. The point was that if you look only at the tangent angle and how close the crack is to parallel, but ignore the rock quality of the placement, you'll get a bimodal failure distribution, with peaks at fall-strength and light-tug-with-your-hand. That doesn't mean there isn't a gray area, just that what puts a placement into that gray area has a lot to do with the rock quality. That is, a placement that might fail well above a body-weight load in good, high friction rock might fail at well below body-weight in slick or crumbly rock. If you only compare similarly hard rock, then cams placed in the rock with the higher coefficient of friction will fail less than those in slicker rock in otherwise identical placements.

I think anybody experienced in placing gear would agree that simply looking at the geometry of the placement, and not the rock its placed in, would consistently result in bad placements. Patto's statement only refers to the geometry of the placement. So does mine.

The gray area comes from the fact that we're not simply looking for parallel placements when placing cams, but also situations that prevent walking, that have good rock, that don't result in a junk placement if they walk, etc.

No, it's just plain silly. You're calling an "exception" nearly every single fall that happens in the real world. I doubt there are many real falls (not counting just slumping onto the piece) that do not cause the cam to either move somewhat, or crack, crush, or dislocate some crystals.

Is there anything when buying a piece of protection, that shows when it will rip out of the wall?
Like how much force is needed to pull it outa the wall?

Does the strength of the protection have anything to do with this?

The point I'm trying to make is that all my experience leads me to suspect that many placements (at least for cams roughly an inch and a half or smaller), placements you and I use every day and call good enough, are squarely in that "gray area".

These placements would, if subjected to a serious fall, fail at significantly below the rated strength of the cam. The reasons are myriad, and not worth going into here. The point is that the notion that a cam is either "good" or "bad" in the real world is simply silly and misleading.

Sure, I could find you placements where I'd bet good money that the cam would fail at it's rated strength, but in the real world, such placements are often nothing more than a pipe dream, and we go with what's "good enough".

The only scary thing, to me, is that I bet that most people wouldn't know the difference between a "good enough" placement and a truly bomber one. Fortunately, it rarely matters, since most of us don't go around taking big whippers most of the time.

GO

I can't speak for cracklover, but if you actually believe that all the things you don't have to consider aren't a MAJOR factor in piece quality, then you really need to travel more, or you misunderstood my defense of your statements.

Is there anything when buying a piece of protection, that shows when it will rip out of the wall?
Like how much force is needed to pull it outa the wall?

Does the strength of the protection have anything to do with this?

Comments like these make me think you climb on really shit rock. I place cams all the way down to the Green ZERO, which is 1/3 of an inch. (Though I haven't falled on greeny.)

Here are some real world tests of trad gear. The sandstone where this gear was placed is renowned for its poor quality for trad gear. (though it isn't as bad as really shitty sandstone.)
http://www.sanguma.org/...ructo/placements.php

Your comments that decent most cams can hole light falls but not big whippers are simply not true for decent cams good rock.

In even the hardest and most parallel of desert sandstone, I'm absolutely sure that a hard fall on a small cam will cause it to track at least a little.

In even the hardest granite, you sometimes must make do with a shallow cam in a pin scar. Expecting these to hold a hard fall is wishful thinking. A buddy of mine recently fell and ripped four such cams from their placements - all of which he thought were truck.

Those are just a couple examples of gear that looks - not perfect, but good enough. And these pieces will certainly hold, but will pull out before they break.

BTW, your link does little to bolster your point. There were only two cams tested, and in both cases, they tracked out, undamaged. In one case, it tracked out even though it was behind a bottleneck, which is the one case where a cam should be absolutely solid. So much for your theory that it either comes out with a tug or hold until it breaks or the rock crumbles

In theory and in most of the time in practice a cam will either pull at very light loads ie a tug with your hand. Or hold until the rock or cam breaks.
.

If you are suggesting that a cam moving out and then stopping is common in cam behaviour then you clearly don't understand the mechanics here. Once a cam moves in the direction of fall then in all likelyhood its not going to stop. (Unless you are talking slight compression movement that is visible on all big cams on even a hand tug.)

I played with both.

Strength or weakness?