A through hole gives chips somewhere to go; a blind hole needs another plan. Match tap style, chamfer, and drill size to the hole, material, and thread requirement.

Carbide has little patience for a shaky setup. Weigh HSS, cobalt, and carbide against the metal, machine rigidity, hole depth, and what happened to the last drill.

Build a cutting station from recurring jobs, with separate storage for cutting edges, bulk supplies, and abrasive wheels.

Pick cutting tools from the operation and material first: drill, tap, mill, deburr, grind, or cut off.