interesting WC superlight rock failure

https://www.facebook.com/john.orr.73/posts/626274192734

;)

Interesting...thanks for sharing.

Those are still my overall favorite wired stoppers ever.

Mmmm that could be a fun metallurgy detective problem - it would be interesting to hear the history of the nut in regards to use and temperature, along with taking a look at the fracture for inclusions or defects in the alloy (7075?)

I seem to remember a recall of these a while ago.

Can anyone remember if it was for these ones?

Yikes - that isn't cool. Still, gotta agree with RadDawg on this one. Even the DMM offsets/peenuts are collecting dust.

It looks like it took a fall and those things aren't rated for very high KN, it doesn't take much force to generate 5kn

The recall wasn't for the Superlights. It was for regular rocks (non anodized I believe).

That thing is beat. If it's really a number one it's had all its color scratched off. Agree with Bear. There's not a lot of metal around the base so that looks like west and tear and nothing to get worked up about.

Actually theres no kinking or fraying of the wire or deformation of the nut itself

Everyone of my nuts has the anodizing thats worn off

One can wear off the anodizing simply by placing and removing enough times ... Even without whippers or hammering

Personally i dont think a nut should crack that way .... The wires might break but i havent seen a nut crack before

;)

I think it is an expanded micro-fracture.

weird
I wonder if thats the first time thats happened to someone

David Gibbs wrote:I think it is an expanded micro-fracture.

He must have dropped it from above 3m. I heard that causes micro fractures.

Why oh why is the cable so bent?

Could be the second pulling too hard or a previous fall.

Seems a key detail to the failure.

As in the cable is held by a steel fitting inside the aluminum nut.

The cables on many a nut can get slightly bent from basically anything

This is true especially for assymetrical nuts

The issue is if you kink the cable enough the wires strands syatt breaking

In the above case the strands look fine and the nut itself shouldnt break

;)

bearbreeder wrote:The cables on many a nut can get slightly bent from basically anything This is true especially for assymetrical nuts The issue is if you kink the cable enough the wires strands syatt breaking In the above case the strands look fine and the nut itself shouldnt break ;)

Generally speaking, I haven't found the fraying to be the result of a massive kink. The individual strands start to fail due to repetitive flexing back and forth (kink, straighten, kink, straighten etc).

The base of those nut has fairly thin metal surrounding the much larger cable. A large force could be enough to break the thin metal while leaving the cable fairly unscathed. (particularly with an off axis load that appears to have happened here) The use of 7075 (vs 6061) also adds to the likely hood that it "cracked" given 7075 is less ductile.

Such a crack is not an indication of a failure that one should be concerned about if one regularly checks their gear. The nut was well used and it was removed via the wire - probably on multiple occasions. And given that the wire is bent there had obviously been some force place on the nut at some point in time. It should have retired long ago. Small nuts should not removed by the wire - they should be tapped with a tool so they are loose then removed.

actually if that crack wasnt there IMO th nut would be just "fine" ...

theres a slight bend in the wire, but the strands are all intact and they dont look stretched (not symmetrical) ... to put it bluntly ive seen more wires that are more bent on X4s right at the shop new ...

and the wear on the anodizing is what you get in about a years climbing if you use yr nuts daily ...

let me rephrase this ... has anyone else seen another nut failure this way?

i would be most interested to hear about it ...

;)

Allen Sanderson wrote:Such a crack is not an indication of a failure that one should be concerned about if one regularly checks their gear. ...

i don't agree with this at all. think about how much force, the DIRECTION of the force, and the LOCATION at which the force would have occurred to cause a fracture like that. i don't think it happened from somebody cleaning the nut by jerking it back and forth.

Have you contacted Wild Country? Would be interesting to hear what they say.

The owner contacted WC according to his fbook

He claims they have been aware of the issue for months

He also says the BMC technical commitee has been contacted as well

Its in the link in my OP

;)