I have recently been quenching blades before grinding them (most recently, a scalpel I made as well. It's a thin piece of steel when it's finished), and I wonder what the advantages and disadvantages of quenching a blade ground are, aside from there being more mass in the blade un-ground. Also, in theory, unground blades would be descaled some due to it being blown off in the quench media or at least losing when martensite forms the same way that happens with a clayed blade for a hamon will.
PS: i forgot to subscrib so this is just to subscribe
Thanks, 👍 I have a fair understanding of heat treating i am getting ready for bed so i am going to read it in the morning, however, in this case, my question what are the advantages and disadvantages of cleaning off the scale and getting the blade it shaped and shiny to quench it, or rough and forged to finish quench then clean and shaping after heat treatment it up well keeping cool. what are the advantages and disadvantages of these approaches?
It depends.. with modern grinders and abrasives hardened steel works almost as easily as annealed so for things like chef knives I forge really close and leave the scale on for hardening.. I do profile grind before hardening so i have 1 have an area free of decarb to check hardness, and 2 to prevent and stress risers from inconsistencies forged into the edge. I have found I get less warping as the decarbed layer from forging is relatively even balancing the stresses in hardening if I grind I would need to get fully bellow the decarb.
on thicker knives it really depends on what I need to do and what material I am working with. If the design calls for areas I need to file details on very shallow hardening steels I would tend to grind most of the time if for no other reason than so I could check it the hamon didn't fall to close to and edge i also grind before hardening the rare times i do Hamon I would also grind 70% of finished as a lot of the interesting effects are relatively shallow.
MP
