Hotiko 4pcs Titanium Coated Countersink Chamfer Tool Deburring Tool Set Metal Wood Drill Bits
Ideal for cutting through metal, aluminum, copper, wood, plastic, PV plates and thin iron plate (hardness
Instructions:
Pilot Hole
First drill the hole in wood or plastic to locate or guide a screw and expand the size according to the tap. Without a pilot hole, the screw may get too tight and either broke the material or snap the screw completely.
Countersink
Install the chamfer drill on the bench drill. If you need to chamfer 16mm hole, you can choose 15-20mm chamfering device. Add water or cutting oil to cool when chamfering.
Clearance Hole
Finally screw on until flush with the horizontal. These bits should use the bench drill. If you use the hand drill, it's easy to shake and affect the chamfering.