Construction Tips - Center Punch

If you've got a mill, you've got broken end-mills. Grab a piece of 3/4" round stock, drill a hole in one end corresponding to the end-mill diameter (here 3/8") and drill and tap it for whatever Allen bolt you have lying around. Chuck up the broken end-mill in a drill and "sharpen" it on the grinder. Insert the end-mill, tighten down the bolt and you've got a pin-point, easily resharpened, doesn't dull easy center punch.