Sharp'inun twist drills

In have had luck with the drill doctor but it has to have pretty new stone in it to work right . doing hundreds of steel doors worth of door hardware really eats the bit collection . could never get the feel for hand grinding them , now sharpening knive's on the grinder I was king of the leather factory , the other guys used to pay me to sharpen spare blades for them whenever they saw me heading for grinder to do my knife .