John Wilson
Well-Known Member
Did I read that correctly that you are grinding vertically on the flat platen with the butt end up? In my experience that is going to cause flatness issues. Doing it that way, I would expect the butt to get thinner than the intended plane. The reason being, the belt always wants to bunch at the first point of contact, building like a wave before running down under the steel. You have to be very careful about your pressure to avoid this. That wave will eat the corner off.
I do a lot of vertical grinding on plungeless blades. To keep flatness, it helps to vary the angle of the knife from vertical and to change this angle every little while to average out the non-flatness of the belt. By angle I’m referring to the attitude of the blade. If straight up and down has the butt pointed at 12 o’clock, I grind some at 12, then 10, 2, 12, 6 (tip pointing to 12)....etc. Those are just random numbers. You get the idea. The point being to randomize the angles to get an average flatness from a non-flat surface.
I do a lot of vertical grinding on plungeless blades. To keep flatness, it helps to vary the angle of the knife from vertical and to change this angle every little while to average out the non-flatness of the belt. By angle I’m referring to the attitude of the blade. If straight up and down has the butt pointed at 12 o’clock, I grind some at 12, then 10, 2, 12, 6 (tip pointing to 12)....etc. Those are just random numbers. You get the idea. The point being to randomize the angles to get an average flatness from a non-flat surface.
