▲ 6 r/knifemaking
What could have caused this?
Both sides of this knife have a rough patch I couldn't sand away.
It's 26c3, professionally heat treated to IIIRC 66HRC.
It looks a bit like a hamon mark which makes sense as this steel is good for hamons.
Could it be an overheating mark from grinding? I don't think it's likely as I was fairly careful and never saw the steel turn blue or even orange. Or is it most likely to be a heat treatment error?
I'm a bit pissed off finding it this late in the process tbh.
u/Franksss — 11 hours ago