any idea what caused the initial failure?
I just shortened a damaged chain with no adverse effects if that is any consolation. it cuts fine.
As with many things, I haven't got a clue what caused it. Judging the guy that I got it from, he may have tried to brush his teeth with it.
I would have expected to see damaged cutters or drivers but all is well. I don't know if the straps are heat teated but if so, it may be from a batch that was too hard. The fractures look brittle as there is no elongation at the fracture. (Sorry, the drunken metallurgist in me talking)