Bill and all,
I’ve made some trial cuts like Bill’s. Pictures at link below. Wanted to see the cut quality for various tpi’s.
The photos below show cuts made with 3 katabas—18tpi, 24tpi, and 13tpi. Fence is 1” high, beveled at 15 degrees. Held saw blade against fence with 2 fingers, as shown in photos. Photos show plan and edge views.
Bill, will send you the 18tpi saw if you’d like. By Heiji.