Sharpening Oregon 91vxl help?

[stig]

That happens a lot when we cut in winter, Jay.
Hit a rock under the snow and you have the heat+instant cooling that makes it near impossible to file the chain.

Mostly I'll just toss it and put a new one on.

 

[woodworkingboy]

That explains it then, Stig, thanks. I guess you could hit a hardened tooth with a torch. More fact than guess work when affecting hardening though.