Bordo reduced shank HSS drills are ground and then a black finish is achieved by steam tempering, a thermal process resulting in a porous tool coating. This surface aids chip flow and heat dissipation. The drill is then ground a second time to achieve a bright finish on the shank and cutting edges.
Specifications
Diameter: 47/64in (18.65mm)
Shank Diameter: 1/2in (12.7mm)
Flute Length: 86mm
Overall Length: 152mm
Point: Notched 118°
Helix: 30°
