Chef Haines wrote:
Are they necessary on a super hard steels like Hap40?
They aren't necessary, but there are instances where it makes sense to use one. In general, if you are sharpening at a super acute angle on steels that are thin and very hard(prone to micro-chipping), a hair-line micro-bevel on the front side can add some strength to the cutting edge. The trade-off is at the expense of achievable sharpness, but you are not sacrificing a whole lot.
Sharpening this knife, which isn't ultra thin to begin with, the first edge I put wasn't very acute. Exercising caution, I decided to do it anyway since my experience with this type of steel in a work environment is limited. I have since put a steeper edge without one finished to an 8k and can vouch this is a well-forged piece of steel. Edge taking, retention, and resistance to micro-chipping, A+++. Hope this makes sense.
Thanks for watching