hamon

[Jack Henry]

Hey guys. So I just started doing my own heat treat and every time I quench I get a hamon. (I am using 1095 steel) This is ok when I want a hamon but sometimes I dont, and then im left with just a wierd looking line that is just visible down the middle of my blade. Ive tried quenching the whole knife and not just the edge and tried quenching vertically but i still get a hamon. Does anyone have anyidea why or how to prevent it?
Thanks in advace -Jack Henry

 

[S.Alexander]

How thick is the steel you are using? Can you go through your HT process?

 

[Stacy E. Apelt - Bladesmith]

On 1095, and an edge quench will almost always make a quench line ( technically, not a hamon). If the temps are right and the steel is thick enough, 1095 may get an auto-hamon even with a full quench. 1095 is a shallow hardening steel, and the distance to the center of the blade is important.

The best way to minimize it is:
Use correct oil type - parks #50.
Quench straight in point first. Don't pull out for 60 seconds.
Select HT temp by experimentation. Try 1450, 1475, and 1495.
Keep blades on the thinner side. 1/8" and less should fully harden in a full quench.