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View Full Version : Arrrggg My mid priced stainless micro chipping



David Metzger
03-15-2012, 03:07 PM
I thinned down a bit on my old stainless blades and then sharpened to about 12 degrees per side. These are medium quality - mostly German knives but with unknown stainless steel. These are not heat treated very hard.

I will have to go back to 20-22 degrees per side. Are these micro chips usually large carbides breaking off or just hitting something it doesn't like? Anyone else have troubles with micro chipping? even with good steels? Even my stainless paring knives are not happy.

What are your results with AEB-L, 12-13c26, CPM 154, Elmax , or the carbon steels, etc?

David

Pensacola Tiger
03-15-2012, 03:27 PM
I'm surprised your edges haven't folded yet. Twelve degrees is too low for middling steel like you have. I have some old Wusthofs that I tried fifteen degrees on before I went back to 20+.

The good news is that by going to 12 degrees you've really thinned behind the edge, so all you have to to is put a bevel of 20-22 degrees on and you should be good to go.

SpikeC
03-15-2012, 06:05 PM
Are you sure they are chips and not dents?

ecchef
03-15-2012, 08:22 PM
That's what I was thinking.

tk59
03-15-2012, 11:01 PM
Any high chromium (maybe 15+%?) is going to have issues at acute angles unless it is pm steel which will do better. In general, below 60 hrc you get mainly deformation which leads to work hardening which leads to chipping. Above 62 hrc you get more chipping and less deformation. And no, at 12-ish deg I don't have any deformation or chipping issues. (Aside from my Henckels/Forschner/Sab stuff.)

David Metzger
03-16-2012, 05:22 PM
Yeah the edge is chipping more than rolling but I will study it more, maybe I can take a couple pics. Maybe my wife is harder on them then I think. A bit of a mystery.

Benuser
03-16-2012, 07:15 PM
I would agree that 12 is a bit low with stainless Germans, but would expect deformation rather than chipping. What will look and feel like micro-chipping is a wire edge, quite common with these. A microbevel, a few edge trailing strokes, at some 17 degree will do in either case. An other suggestion would be to sharpen at some 800 grit, strop and deburr at 2000 and STOP