A: From the tip of the bit to the beginning of the countersink on the #8 is approximately 1-3/4” give or take a millimeter for production tolerance. The shortest I can comfortably bring the countersink is 1-7/16”. However it can be taken as short as you’d like at the risk of damaging the upper portion of the bit.
A: Penetration depth is adjustable as all bits contain an adjustable set screw.
A: I would wager to say no! This is intended to be a woodworking bit for soft & hardwoods and other soft materials. Twist drill for metals typically have consistent size from the shank to the tip.
A: Hi Tim, theses countersink bits will not go through metal.