Relatively new to knife making and generally send my blades out for HT but thought I would try to heat treat some 1095. Heated my blank (flat ground) to non-magnetic in my 2-brick forge heated w MAP torch, held for a couple of minutes and quenched in 120 degree canola oil, came out straight, tempered in oven at 400 degrees for one hour twice, file skated so I assumed everything was fine. After heat treating started finishing blade, but when I got to 800 grit started to notice fine irregular scratches/cracks/trails and realized something might be wrong. As I have progressed to finer grits and the sanding scratches have become less I can see more of the lines/stress fractures(?). They are most prominent near the spine, none can be seen in the lower halve of the blade. They are very fine and not noticeable unless you look very close (or are a maker).
Any idea what I did wrong? My guess is that I overheated the steel but I really have no idea. After bringing the blade to dull red I turned the torch to the lowest setting to keep it from getting hotter. I rotated the blade frequently but generally kept the edge out of the hottest part of the forge.
Should I have normalized prior to grinding?
I tried to take a picture but they are hard to see and impossible to photograph, at least for me.
Any idea what I did wrong? My guess is that I overheated the steel but I really have no idea. After bringing the blade to dull red I turned the torch to the lowest setting to keep it from getting hotter. I rotated the blade frequently but generally kept the edge out of the hottest part of the forge.
Should I have normalized prior to grinding?
I tried to take a picture but they are hard to see and impossible to photograph, at least for me.