For steel, a bi-metal hole saw with a high-speed-steel edge is the minimum; carbide-tipped saws last far longer in stainless and thicker plate. Tooth pitch follows the same three-teeth rule as any saw — finer for thin material.
The arbor matters as much as the saw: it carries the pilot drill and must fit your chuck. Quick-change arbors save time when you switch sizes often.
The questions welders ask
Why do hole saws blunt so fast in steel?
Speed and heat, almost always. They need to run far slower than in wood — a few hundred rpm for larger sizes — with steady pressure and cutting fluid. Run at wood speeds they blue and blunt within one hole.
Last reviewed 2026-08-14