Spigot Mounted
Although the edges of the holes will be very slightly chamfered to eliminate the sharpness, this does not constitute a countersink.
Conical Countersinks
Conical countersinks (60°, 80° or 90°)
A° = c/sink angle d = hole diameter D = open diameter
Spherical Countersinks
Spherical countersinks (R14,R16,R18,R22)
R = c/sink radius d = hole diameter D = open diameter
