Engineering - Information Tables

Drilling Speeds

The rpms that you set your drilling machine at can be calculated from the following formulae and table of cutting speeds. Rev/min = ( Metres/min X 1000 ) / ( 3.142 X D )
where D = Diameter of the Drill
and Metres/min is acquired from the table below.

MATERIAL SPEED (Metres/min)
Aluminium & aluminium alloys 30 to 61
Brass 30 to 46
Leaded brass 30 to 61
Bronze 30 to 61
High tensile bronze 21 to 30
Grey cast iron 24 to 30
Copper 30 to 46
Monel metal 6 to 15
Free cutting mild steel 24 to 30
High tensile steel 15 to 21