Edge Iconsistencies

[Robert Ptacel]

While sharpening some kitchen knives ( Henckels International) I noticed they weren't as sharp as I like. Examination under magnification showed micro-chips. I used to think it was my technique but other knives I could pop hairs with. I have come to the conclusion it must be their heat treat and not my technique. I used to beat myself up over this but heat treatment is out of my control. The knives seem to chip the more I sharpen them while others sharpen perfectly.Any metallurgist out there care to comment?

 

[nozh2002]

While sharpening some kitchen knives ( Henckels International) I noticed they weren't as sharp as I like. Examination under magnification showed micro-chips. I used to think it was my technique but other knives I could pop hairs with. I have come to the conclusion it must be their heat treat and not my technique. I used to beat myself up over this but heat treatment is out of my control. The knives seem to chip the more I sharpen them while others sharpen perfectly.Any metallurgist out there care to comment?

I have similar problem with some of my Shirogami knives, you diamond stones and ceramic is just too hard for their HT. I had to switch to waterstones and it fixed the problem.

Thanks, Vassili.

 

[ryan06]

I noticed the same thing myself. I have an old Henckels kitchen knife that I sharpened on a sharpmaker, chipped the edge in two places. That is when I noticed that the medium rods for my sharpmaker had a few nicks in them. I then used a Lansky system to get the edge back on the knife. All is good now.

 

[Robert Ptacel]

I wasn't picking on the Henckels specifically. I have noticed this on other knives and have come to the conclusion it is the variability in heat treat. Typically Buck knives sharpen up smooth as silk with no evidence of micro-chips. Spyderco is another who has hair popping edges. As one bladesmith has said the most important thing is blade grind and heat treat not necessarily the steel. I just posted this so others wouldn't blame themselves when a knife doesn't come up to standards. I know I used to rack my brain to think what I was doing wrong. I am not a newcomer to sharpening having worked in a meatpacking plant for 20 years.