What I have been doing is cutting a strip of sandpaper to match the DMT stone holder shape and taping it in place. This helps me maintain the same angle. Also I have only been moving in one direction. No back and forth movements with the paper. Once I get a nice mirror finish the blade just doesn't feel sharp any more. But if after I use the sandpaper I switch back to the extra extra fine DMT diamond board and go over it again a few times, the edge goes right back to sharp. It is extremely sharp at this point. I'm happy with how sharp the blade is but it would be very cool to keep the mirror polished edge. Maybe the difference of the thickness of the board vs the thickness of the sandpaper is enough to throw the angle off. I will try to make a spacer for the sandpaper and see what happens.