Last weekend, I spend a few hours sharpening a whole bunch of knives, using Suihiro Cerax 1000 and 3000, and Suehiro Rika 5000 stones. The knives included Wüsthof, Opinel Carbone, Aogami #2, White #2, SG-2, and HAP-40 steels.
I figured that this would be a good opportunity to figure out what grit finish I prefer for what kind of knife. Here are some observations.
- For the Wüsthof knives, a 1000 finish followed by a few swipes on a strop with green compound is more than adequate. They get really sharp, somewhat toothy, and following up with a 3000-grit stone doesn't make them cut any better. (If anything, slightly worse for tomatoes.)
The one exception where I do like a finer edge is for my boning knife and my (flexible) fish filleting knife. There, it does pay to go all the way to 5000. But I'm not cutting tomatoes with those knives.
- For the Opinel knives 1000-grit grit is plenty enough. Stepping up to 3000 grit doesn't really make much of a difference.
- With powdered steel knives (SG-2 and HAP-40), I found that they cut well after the 1000 stone and better after the 3000 stone. Still going through tomatoes perfectly. I then tried a 5000 finish. The knives were objectively sharper, slicing through paper with less effort and less noise. But they didn't work that well for tomatoes anymore. There was this tendency for the blade to glide on the skin before starting the cut. After I roughed them up a little on the 3000 stone again, they worked better for tomatoes.
- The Aogami #2 and white #2 knives kept improving. Very good after the 3000 stone, and even better after the 5000 stone, both with paper and with tomato.
So, this is my take-away:
- For Wüsthof, Opinel, and similar soft-steel knives, 1000 is the sweet spot. 5000 will make them cut a little better with proteins, so this is worth doing for something like a boning knife.
- PM steels do get sharper at 5000 vs 3000 (at least when cutting paper) but, to me, don't work as well for waxy skins, so 3000 is the sweet spot for me. (3000 also works a treat when they lose the edge just a little, to freshen them up.)
- The Aogami #2 and white #2 knives just get sharper as I follow the progression. 5000 is the sweet spot for me, except possibly for my Yanagiba, where I tend to go to 10000 because I can (but I'm not sure that the difference is really all that noticeable).