Well, I have been playing with Wa handles for a little bit with my KMG 2x72 belt sander. I made up a little jig to try to square up the blocks, but with a belt sander, the belt bows out a bit when pressure is applied to it, so it doesn't give a very square end and with a 2" wide belt, it's a tight fit. I would angle the platen to cut the bevels on an Octagon handle, but wasn't really happy with the results. They look and feel OK, but they weren't what I wanted. So I broke down and bought this!
12" Disc Sander:
I made lots of dust today. I had a Wa handle with Cocobolo and Satinwood and another with Burmese Blackwood and Cocobolo, both bit the dust, but I learned how to work the disc sander. Next two were Burmese Blackwood ferrule and Cocobolo bodies. One is for my 210mm Tanaka KU and the other is for the 240mm Tojiro ITK Kiritsuke. I did a dowel in both pieces, but not showing at the end of the ferrule and drilled a 3/16" hole thru the ferrule and once it was all glued together, I drilled the 3/16" hole down into the dowel and then used small rasps and files to fit the tang to the slot. The Tanaka handle is a nice length and feels good, but is a bit on the small side. When I evened out the bevels, I cut farther than I wanted, so it's kind of a Diamond shape with flattened points. The flats are like 3/16"-1/4" or so, so it's not pointy in the hand.
Then I decided to regrind and thin the Tanaka Blue KU gyuto and bring the main grind up a bit higher on the blade and thin behind the edge a touch and polish some of the KU finish.
Then the boo boo happened
I had the Tanaka on top of my drill press and was drilling the blocks for the Kiritsuke handle. I forgot the drill press vibrates and the Tanaka fell off and landed edge first on the back of my middle finger, bounced off and sliced 1.5" down the side of one of my plastic storage bins that was on the floor. The knife survived with a little nick on the edge, but I got a nasty slice on the top of my finger. So I ran inside, washed and Hydrogen Peroxide flushed the cut, put a bandaid on and electrical tape and went back to work.
Got the ITK Kiritsuke handle finished. I didn't do much of a taper to this one and cut a steeper, deeper angle on the bottom bevels and a slightly wider and less angled bevel at the top of the handle. It feels more like an Oval handle at the top and a Wa Octagon at the bottom.
Handle close ups:
With the disc sander, it is MUCH easier to square up the ferrule/main body material to each other and also get the handle shape and tapers in than it was with the KMG. I used the Disc Sander for roughing in the bevels (maybe 80 grit disc?) and then used a Granite Reference Plate to hand sand 100, 220 grit, and then 320, 400, 600 on a cork block. Went pretty easily to hand sand the materials, maybe 10-15 min per handle if that? I'm glad I went with the 12" disc sander, really makes these much less stressful to make!