I recently bought the Japanese waterstone for my T4. I tried it on a chisel after using the SG-200 stone and can't get the entire sharpened surface to shine. My SG-200 is older and a lesser diameter than the new Japanese stone and I'm guessing the difference in the radius between the two stones is allowing each stone to touch a different part of my chisel.
Right now I'm resigned to maybe only being able to use the Japanese waterstone on the tip of my chisel.
I also have a nice chisel sharpening kit that I can use with my various other abrasives, but that gives my the typical flat grind that also does not get fully polished with the Japanese waterstone.
Any ideas on how to match up the grinding on the two different stones? Thanks!
You cannot match the grind, because the diameters of the wheel are different. Just put a secondary bevel on the chisel with the japanese stone, that's what I do.
If you're willing to go down this rabbit hole, you will want to check this thread (https://forum.tormek.com/index.php/topic,4326.0.html), which includes a useful spreadsheet in the first post, along with very a detailed discussion of how it was elaborated by @Gilles.