I resharpened a couple of stainless knives, one of which was dulled on the ceramic rod. I used a different procedure by using my Norton Economy stone coarse & fine stone, then the ceramic rod. This was done free hand, so the angle is somewhere between 10 and 15 degrees per side. This procedure resulted in an edge that would tree top head hair. I have not found dulling with the ceramic rod specifically to be detrimental. Dulling by lightly cutting into the abrasive appears to produce a two sided burr, even on abrasives other than the ceramic rod. As far as the sharpness tests I use are able to tell, there isn't a detrimental effect on sharpness if the edge is dulled by lightly cutting into the abrasive prior to sharpening. Further testing will need to be done to confirm this, and this is limited to low alloy carbon steels and simple 420HC and similar stainless steels.
For this effect alone, I am somewhat curious about the preference for non-stainless steels in Japanese kitchen cutlery. I'm also curious if the edge finished on the ceramics of the Sharpmaker is less susceptible to corrosion than the edge finished on my 4k water stone. I may have to sacrifice some onions and find out.
(12-13-2017, 10:19 AM)EOU Wrote: Interesting comments all round Me2. We took note of your comment " I used the larger knife, a 175 mm Misuzu Bunka, to cut some apples and onions, and the edge dulled from corrosion." We assume that you are referring to the acidic effect on the edge? Interesting because we've noted and measured the effects of oxidation on edges before but hadn't really considered possible corrosive effects. That would be a whole new area of interest, particularly for kitchen users.
For this effect alone, I am somewhat curious about the preference for non-stainless steels in Japanese kitchen cutlery. I'm also curious if the edge finished on the ceramics of the Sharpmaker is less susceptible to corrosion than the edge finished on my 4k water stone. I may have to sacrifice some onions and find out.