Finish the 4 facet drill grinding jig then grind and test a drill. This jig is made from a kit by Hemming way kits (link to web site below) www.hemingwayk...
Thanks. Nice jig too! Taking the back edges off drills has been used under different circumstances, I think on thin plate/sheet, with differing pressure. I wonder if an extra 20ish percent speed is worth risking a fragile tip for. How about double facet at different gradients next.