it's not a bannable offense for presenting pertinent info and reasons why the info and ideas that you have been presenting are erroneous. you're the one denouncing the entire climbing gear industry for the "biggest screw-up in history"

that coming from an idiot who is capable of this kind of self-contradicting nonsense:

I have some pictures of hook and pin carabiners working properly and catching falls and being pulled to high loads but since none of them broke, I didn't post them. The collection includes about 3 million photos so it's good evidence that I'm right and that the hook and pin are way over-engineered and should be reduced in size to remove some unwanted weight.

Hmmm... that sounds like a bad argument. I'll have to come up with some real scientific engineering information or else I'll sound like an idiot making outlandish claims. Maybe if I post one or two of the pictures, it will be good evidence.

Dave

Thanks for your professional contribution to this post by continuously calling me names.

java lava bava
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Hahahaha I read the whole thread.

For gods sakes Majid this has got to be your biggest scientific analysis here yet. LOL

The great thing about this thread though is it brought out some great analysis from the various contributers.

Carry on ......

He's sleeping right now. I'll tell him later when he wakes up.

Majid, this thread is sooo funny ..... LOL

So what do you think ?

Gates are known to open on high fallfactors (>1.7)
due to radial vibrations.
This is proven by some frenchies in 1989 with a high speed camera on drop test.

not being any sort of engineer myself, and having minimal knowledge of this whole matter, i pose this question by extrapolating from some other observations...
i've noticed, working with farm equipment, that when using something that runs on a PTO (drive shaft powering equipment from tractor) that if you make the horrible mistake of using a regular pin or bolt in place of the sheer pin, if strain is placed on the system (if you hang up the equipment - e.g bushhog on a rock/stump), you get catastrophic results (mind you, i've not made this mistake myself, but i have seen the damage done). my point is that the pin, is actually the last thing to fail. the metal of the much larger, and theoretically more sturdy, PTO shaft warps first (or you get other damage). my theory was that it is because the pin (despite being small) has so little room to warp compared to the longer single metal pieces of the PTO. so, applied to the world of biners, it seems logical to me that the pin may indeed engage and keep things safe for a while, until the rest of the biner starts to warp, thus pulling the hook away from/off of the pin, while the pin/hook itself never failed. it makes sense to me that if the pin were longer (allowing more area over which to warp) it would be the first thing to fail, but it's not, so it engages, holds for a while, the rest of the biner warps, pin disengages, and then we say "what the hell? did that pin even do any good?"

edit (addition): if that's the case, it seems like we would see similar results despite the locking mechanism. after all in a pull test, SOMETHING eventually fails, and i would think it to be the longest single piece of metal since that would allow the "room" to warp (unless of course you used some super small pin or weak/thin hook - or keylock)

i'd be curious to hear feedback on this odd application of NC-redneck tractor equipment knowledge.

reference is
Sicherheit in Fels und Eis I
published by the german alpine club (DAV) safety council
I guess it's not available in english
The vibrations are initiated by the movement of the biner when it's pulled into the direction of loading.
They state you can't see it with your bare eye, but everytime it happened the biners broke.

sorry but I don't have the direct french reference
and the other one is written in german

so, applied to the world of biners, it seems logical to me that the pin may indeed engage and keep things safe for a while, until the rest of the biner starts to warp, thus pulling the hook away from/off of the pin, while the pin/hook itself never failed. it makes sense to me that if the pin were longer (allowing more area over which to warp) it would be the first thing to fail, but it's not, so it engages, holds for a while, the rest of the biner warps, pin disengages, and then we say "what the hell? did that pin even do any good?"

Shear pins are made of soft metal that shears easily - hence the name. The shear pin is meant to break to prevent damage to the rest of the system which contains much more expensive and hard to replace components like gear boxes, transmissions, bearings, etc.

In the case of a carabiner, any failure is a catastrophic failure. There is no sacrificial part or design within a carabiner to save another part of the device. When it breaks, you throw it away... if you survive.

Carabiners are made the way they are for a reason. That reason combines all the requirements from strength to usability to cost effectiveness to weight and makes compromises to achieve an acceptable level of each. Some carabiners focus on certain aspects which dictate their characteristics, but all (at least the ones I'm willing to use) meet the minimum standard for safety set by the UIAA.

Carve the notch deeper to hold onto the pin longer and you'll end up with a carabiner that locks closed after a big fall. Yes, it may be a little stronger, but do you really want to be locked to your carabiner half-way up the rock after that painful factor 1.5 fall? Probably not.

You've been led astray by Majid's postulation. A biner simply doesn't fail the way he states that it does.

This simply doesn't happen, unless the gate is held open or flutters open:
[image]http://img522.imageshack.us/img522/521/81798928iq1.jpg[/image]

This does:
http://youtube.com/watch?v=ZyVD0FBLiFQ

If you watch the above video, you'll see that the hook actually will engage *more* with the pin, until the biner breaks at the elbow where it's bent.

GO

Trench

I have a question for you;

During a lead fall where your life depends on every pieces of protections; would like to see a biner become locked during a FF 1.7 or have the gate open cause you want to reuse the $5.50 biner?

Go
The video is invalid since most mfgs use shackles with @ 5 mm in diameter and not some fat shackles that applies forces on the entire upper part and the bottom part of the elbow of the"D".

To make a valid test, he should realistically use a bolt hanger on one side and a 5 mm steel cable or a 11 mm rope.

This thread is hilarious. I like how Majid agrees with people that prove him incorrect. When he does it fast enough it stops people from reading the posts that prove him wrong.

Well, this thread has pushed me over the edge. I've sat by and let others fight it. From now on, ever time Majid posts complete garbage, I'm going to post "FAIL."

Majid - D shaped biners are better then ovals because they are stronger when loaded. The are stronger because they put the metal more in tension, rather then bending. The straight side is put into tension (mostly) because there is no (little) bending moment. An oval biner causes bending moments on BOTH sides.

Majid - You will never see a biner break because of the pin. Even though the pin side is much weaker then the spine side, it sees a much lower load. Most of the load is "channeled" through the spine. The spine probably sees 3 to 30x the force of the pin side.

The pin prevents the biner from plastically deforming into a much weaker shape.

This is all done on purpose! Because it is BETTER. Just stop posting garbage. Please.

Oh yea...

YOU FAIL!

I'd prefer neither - to have the carabiner not break and not be permanently locked. That's what currently available carabiners do now, except when extraneous circumstances ("gate flutter" or rock contact) cause the gate to open during fall.