What Drill Bit

Drilling metal & metal fasteners

Drilling into metal, and the screws that go into it. Two tools cover the fastener people mix up most: the self-tapping screw pilot-hole size, and whether a self-drilling (TEK) screw will get through your steel. The self-tapping / self-drilling trip-up guide is being built and slots in as it ships.

Self-tapping screwsPilot-hole size for sheet-metal screws by gauge and metal thickness — self-tapping screws still need a pilot in metal. Self-drilling (TEK) screwsNo pilot needed — the drill-point tip bores its own hole. Pick the point number and steel thickness to see whether it'll get through.

What’s here now

What drill bit for metal?The bit-type guide: how a metal twist bit is shaped, the 118° vs 135° split point, and cobalt vs HSS for steel and stainless.

Elsewhere on What Drill Bit

Wood hubWall & Masonry hubSizes & Charts hubGuides

These are general guidance sizes cross-referenced from common woodworking sources. For structural, load-bearing, or manufacturer-specific work, follow the fastener manufacturer’s or an engineer’s specifications.