---
title: "Drill bit — which one for which job"
description: "13 answers on choosing the right drill bit for the material, with the reason behind each and what fails."
url: https://atoneplace.net/which/drill-bit/
site: "At One Place"
---

# Drill bit

13 materials and what works on each.

| For | Use | First alternative |
| --- | --- | --- |
| Tile | A spear-point carbide or diamond bit in rotary mode only — hammer action shatters tile, every time. | Diamond core bit |
| Metal | An HSS twist drill, ideally with a 135° split point, run slowly with firm pressure and cutting fluid. | HSS with 135° split point |
| Concrete | An SDS-plus carbide bit in a rotary hammer — a normal hammer drill will get there eventually and blunt several bits doing it. | Four-cutter carbide head |
| Masonry | A carbide-tipped masonry bit in hammer mode for brick and block; step up to an SDS rotary hammer above about 10 mm. | SDS-plus bit and rotary hammer |
| Porcelain tile | A diamond core bit, cooled with water, at low speed — carbide spear points do not cut porcelain. | Wet diamond core with a guide jig |
| Stainless steel | A cobalt bit at low speed with heavy constant pressure and cutting fluid — and never let it stop cutting. | Solid carbide bit |
| Wood | A brad point bit for clean holes up to about 13 mm; an auger for depth and a Forstner for a flat bottom. | Standard HSS twist drill |
| Plasterboard (drywall) | Almost none — an ordinary HSS or brad point bit in rotary mode, and the real question is which fixing goes in the hole. | Self-drilling plasterboard anchor |
| Glass | A spear-point carbide or a diamond bit, run slowly under water — and toughened glass cannot be drilled at all. | Diamond hole saw |
| Plastic | An HSS bit ground to a shallower rake, or a plastic-specific bit, at low speed with a backing board — acrylic especially will crack. | Standard HSS bit |
| Hardened steel | Solid carbide in a rigid setup, or soften the spot first — HSS and cobalt cannot cut anything much above 50 HRC. | Carbide-tipped masonry bit, reground |
| Aluminium | A sharp HSS bit at high speed with a wax or paraffin lubricant — the problem is aluminium sticking to the bit, not hardness. | HSS with a polished or bright finish |
| Large holes in wood | Spade for speed and roughness, auger for depth, Forstner for a clean flat bottom, hole saw for big diameters in thin stock. | Auger bit |

- [Which drill bit should I use for tile?](https://atoneplace.net/which/drill-bit-tile/) — A spear-point carbide or diamond bit in rotary mode only — hammer action shatters tile, every time.
- [Which drill bit should I use for metal?](https://atoneplace.net/which/drill-bit-metal/) — An HSS twist drill, ideally with a 135° split point, run slowly with firm pressure and cutting fluid.
- [Which drill bit should I use for concrete?](https://atoneplace.net/which/drill-bit-concrete/) — An SDS-plus carbide bit in a rotary hammer — a normal hammer drill will get there eventually and blunt several bits doing it.
- [Which drill bit should I use for masonry?](https://atoneplace.net/which/drill-bit-masonry/) — A carbide-tipped masonry bit in hammer mode for brick and block; step up to an SDS rotary hammer above about 10 mm.
- [Which drill bit should I use for porcelain tile?](https://atoneplace.net/which/drill-bit-porcelain-tile/) — A diamond core bit, cooled with water, at low speed — carbide spear points do not cut porcelain.
- [Which drill bit should I use for stainless steel?](https://atoneplace.net/which/drill-bit-stainless-steel/) — A cobalt bit at low speed with heavy constant pressure and cutting fluid — and never let it stop cutting.
- [Which drill bit should I use for wood?](https://atoneplace.net/which/drill-bit-wood/) — A brad point bit for clean holes up to about 13 mm; an auger for depth and a Forstner for a flat bottom.
- [Which drill bit should I use for plasterboard?](https://atoneplace.net/which/drill-bit-plasterboard/) — Almost none — an ordinary HSS or brad point bit in rotary mode, and the real question is which fixing goes in the hole.
- [Which drill bit should I use for glass?](https://atoneplace.net/which/drill-bit-glass/) — A spear-point carbide or a diamond bit, run slowly under water — and toughened glass cannot be drilled at all.
- [Which drill bit should I use for plastic?](https://atoneplace.net/which/drill-bit-plastic/) — An HSS bit ground to a shallower rake, or a plastic-specific bit, at low speed with a backing board — acrylic especially will crack.
- [Which drill bit will go through hardened steel?](https://atoneplace.net/which/drill-bit-hardened-steel/) — Solid carbide in a rigid setup, or soften the spot first — HSS and cobalt cannot cut anything much above 50 HRC.
- [Which drill bit should I use for aluminium?](https://atoneplace.net/which/drill-bit-aluminium/) — A sharp HSS bit at high speed with a wax or paraffin lubricant — the problem is aluminium sticking to the bit, not hardness.
- [Which bit should I use for large holes in wood?](https://atoneplace.net/which/drill-bit-large-holes-wood/) — Spade for speed and roughness, auger for depth, Forstner for a clean flat bottom, hole saw for big diameters in thin stock.