How to Sharpen Used and Dull Drill Bits by hand
Have you found some of your used twist drill bits aren't cutting like they used to? you can't even get through wood or soft metals anymore without creating a plume of smoke and high shrieking squeaks. Well before you head over to the hardware store to buy a new box of drill bits, try this simple technique first and save yourself a lot of time and money! Follow these steps and you can transform your used, dull, chipped, broken, or otherwise useless drill bit, into a prime hole blasting instrument.
Material:
A dull or chipped twist drill bit
A bench grinder or belt sander
Warning:
DO NOT wear gloves as they can actually get caught into the sharpening device and pull you in. Be mindful and deliberate about where you position yourself on the sharpening device. And you should probably wear safety glasses too.
Steps:
Know your drill bit There are many features on a drill bit that can be defined. For speed sake, were only worried about 3 basic features on the bit: the lip, land, and chisel.
Find out why drills chip and dull the landing force behind the drill bit can not support the forces exerted by the drilling operation, that will cause bits chip. So make sure your landing has a curved shape to it. There are two reason will cuase make the bits become dull bits. One is the chisel is having trouble smearing the material to the lip and needs to be re-defined on the face of the bit. the other is the lip is rolling over and needs to be re-sharpened so that it pushes directly into the work-piece
Prepare the drill bits run a file across any burrs that may be on the shank to remove it.
You can choose a bench grinder or a belt sander as your sharpening tool
Hold the bits by the shank in your left hand and the hold the head by your right hand. Raising the left hand while applying pressure to the sharpening device to cut the landing
Shape the chisel
Shape the landing
Combine cuting, shapping and rotating while sharpening to make the very good cut on the drill bit face