UKC

I have just got back from a VF holiday, and am due to go out again this weekend....(I know, lucky B eh?). Thing is, I have just given my sons lanyard a fettling, and noticed quite a lot of wear on the inside of the broad end, where it is rubbing on the wires. I think this was accentuated last year when a pal borrowed it to go over the bridge on the Jeggihorn, and he is a wee chap, and didn't think to lengthen it, more sort of dragged the krabs semi-suspended. I never thought to check it really until now, when the springs needed a lubing.
It has only done about a dozen routes, but the wear is about just under 1mm deep, and 4-5mm across......
Will the consensus answer be what I expect it to be..........?

In reply to JohnnyW:

1mm of wear doesn't sound too bad. However, if in doubt replace.

In reply to JohnnyW: There's quite a good article on exactly this on the Black Diamond website. Basically, the crab is pretty unlikely to be significantly compromised for strength (I think) with the amount of wear you describe but could start to be damaging to ropes if you were to use it as a runner in a lead system. If all you're doing with it is clipping it into cables on VF I would think you are probably fine for the time being but I'd keep an eye on it and retire if it gets dramatically worse, especially bearing in mind that VF Biners can potentially get subjected to big factor falls.

In reply to JohnnyW:
Thanks for the reply, I will check out the site.
I only use the Krabs for the VF lanyard, and they do seem pretty bulletproof otherwise.

In reply to JohnnyW: If you are needing to ask about something that could potentially play games on your mind then replace it.

In reply to JohnnyW:

if you take a photo...

In reply to neil the weak:

The Black Diamond article concluded that a groove actually helps the rope to locate to be at the strongest point of the karabiner, beside the spine. The physics of via ferrata falls are different.

>VF Biners can potentially get subjected to big factor falls.

That's what the lanyard is for, via ferrata karabiners are no stronger or more able to deal with high impact falls. The only exceptions would arise through misuse.

In reply to gabriel_m:


That's, I hope, for the intended groove in the design of the krab. Not the mentioned knicks or grooves caused by excessive use, which are usually rough sharp and generally not beneficial for the rope.

In reply to JohnnyW:

You could ask someone involved with the safety of climbing walls. I can't remember off the top of my head, but I think they allow something like 30% of the thickness to wear before they are considered dangerous. Having said that, I think most walls replace their krabs well before that!

In reply to frodostickel:
The grooves were from excessive wear and tear through use as lower off karabiners. They were not the tiny dimples some manufacturers use in their designs.

In reply to gabriel_m: Not True I'm afraid Via ferrata krabs are tested to a different standard to normal krabs which includes loading over an edge (see the uiaa website for further details).

Dankeshun,,,,,Bitteshun

In reply to frodostickel:

Actually no, krabs that were 25% worn through from the crags were found to take greater force to break than brand new ones!

After reading the Black Diamond QC blog thoroughly, I would retire at about 30% wear, or at any point if a rough edge developed which could sever a rope.
The odd millimetre dimple is just a souvenir of good times.

My partner's ATC-XP is slightly worn on one side around the high friction grooves, but the wear pattern is nice and rounded without sharp edges, so it's fine.

In reply to nealh:
I just meant that via ferrata karabiners are not subject to higher impact forces than any other karabiners when in use, so there is no additional need for the user to ensure that they are sound. It goes without saying that they have their own standard, as they can't be sold as climbing karabiners.

In reply to syv_k:
The test involved increasing a static load until failure. That is something which will extremely unlikely to happen in climbing. If you plan on falling onto a karabiner which has 30% less material at the crucial point, go for it but don't think that that article is on your side. This is even more important for I-beam style karabiners, where a reduction in material leads to a smaller radius for the rope.

Personally on a traditional round bar karabiner I wouldn't worry too much, but on something like a Phantom the lack of metal would concern me.

I think you may have misunderstood my post. I was not suggesting that VF Biners are stronger, I was pointing out that they are (roughly) the same strength as everything else and because they can potentially be subjected to particularly violent falls I would take at least as much care with retiral of them as normal gear, maybe more.

If you are suggesting that the use of a lanyard takes the fall factor back down to the sort of impact forces you would see in a normal lead fall, then you are wrong I think. They do reduce the impact in a nasty VF fall (say a 5m plummet down a cable), but from only from one that snaps all your gear and kills you (without a lanyard) to a horribly high impact but survivable one with. Even with the use of a lanyard you are still looking at a very high factor type fall (ie high peak impact forces).

In reply to neil the weak:
If I remember correctly the standard for via ferrate kits requires that the maximum possible impact force from a 5m fall is 6kN. So you really don't have to worry any more about your via ferrata karabiners than you do your climbing karabiners.

The weakest link in the chain is rated at four times higher than the highest load it can receive, and probably fails at higher. Whereas in climbing the weakest link could be extremely close to the highest possible loads, in the case of small nuts and cams.