When sharpening single-bevel Japanese knives, I used to polish the back flat side on bench stones, then grind the beveled side on Tormek.
But yesterday we got a dozen of single-bevel Japanese knives to do, and I told myself there should be a better way.
And yes, it is. Our new procedure follows.
We are getting 70-90 BESS on the sharpness tester.
Using 2 Tormek machines, one with the Japanese SJ wheel and the FVB, and another with #200 (or #400) and #1000 grinding wheels, it takes 10-15 min per knife.
1. Measure the existing edge angle with a laser protractor, if ordered to reproduce. Our default for quality high-carbon Japanese knives is 16 degrees; lower-end knives we sharpen at 20 degrees.

2. Clamp in a knife jig.
Using
our Frontal Vertical Base at the front of the Tormek, position the knife so that the backside edge rests on the wheel with the knife jig parallel to the top of your Tormek.
Polish the flat back on the Japanese wheel SJ-250 horizontally - initially do just 2 passes.
You will get a narrow polished strip all along the edge; don't bother if it is not ideally uniform at this step.


3. Set the grinding angle using our computer software "Grinding Angle Setter".

4. Grind the bevel side into the edge on a coarse wheel, e.g. SG-250 grit 220, or diamond wheel DC-250, or a CBN wheel.

5. Using our Frontal Vertical Base at the front of the Tormek, polish the flat back on the Japanese wheel SJ-250 horizontally; usually 1 pass is OK.

6. With the help of our computer software "Grinding Angle Setter" calculate the Universal Support height for the next grinding wheel.
Grind the bevel side into the edge on a fine wheel, e.g. a 10” Japanese wheel JIS 800, or a diamond or CBN wheel #1000-1200.
Typically it takes 2-4 passes.

7. With the help of our software for the Frontal Vertical Base calculate the Universal Support height for honing on the leather wheel.

8. Hone the beveled side at the edge angle on the Tormek leather wheel with the Tormek honing paste; typically 2-4 passes.

9. Using the Frontal Vertical Base, deburr the flat back on the Japanese wheel SJ-250 by 1 horizontal pass.

10. Finish on a hanging strop by 6-10 passes alternating sides.

11. Test sharpness.
Works like a charm for quality high-carbon knives.
However, with softer knives like Kamikoto etc, requires an extra step to remove the wire edge. We do it by honing on a rock-hard felt wheel on Tormek with 1-micron diamonds @ +3 degree higher than the edge angle, controlled by our FVB, alternating with the flat back of the knife on the same felt freehand at an angle just clearing the knife jig, x 3 passes.