Which blade cuts metal?
Which blade cuts metal?
A bi-metal or carbide-tooth blade with at least three teeth in the cut — that tooth-count rule matters more than the machine.
The three-tooth rule governs everything: at least three teeth must be in contact with the material at all times, or a tooth catches the edge, is loaded sideways and breaks off. That is why thin-wall tube needs 24 or 32 TPI and solid bar wants 14 to 18, and why a coarse blade on thin sheet destroys itself immediately. Speed is the other variable — metal cutting is slow, and heat is what blunts a blade, so the correct approach is low speed with steady pressure and cutting fluid, exactly the opposite of cutting wood. Never fit a metal-cutting disc to a saw that runs faster than the disc's rated speed, and never fit a wood blade to a metal cut: the tooth geometry grabs and the blade can shatter.
The options, ranked
| Option | Good at | Bad at |
|---|---|---|
| Bi-metal blade (bandsaw, jigsaw, reciprocating saw) | Hardened teeth on a flexible spring-steel back, so it cuts hard material without snapping. | Strips its teeth instantly if the pitch is too coarse for thin material. |
| Carbide-tooth metal cutting circular blade | Fast, cold, accurate cuts in steel section with a clean edge and no shower of sparks. | Expensive, and it must be run in a saw geared for the correct speed — not a wood saw. |
| Abrasive cut-off disc | Cheap and cuts almost anything, including hardened steel. | Showers sparks, heats the workpiece and leaves a burnt edge; the disc wears down as it goes. |
| Hacksaw | Controllable and quiet, and 24 or 32 TPI is right for tube and sheet. | Slow, and using an 18 TPI blade on thin tube strips teeth within a few strokes. |
Technique that changes the outcome
- Match the pitch to the material thickness — three teeth in the cut, minimum
- Clamp the work; anything that moves grabs the blade
- Cut slowly with steady pressure and use cutting fluid where possible
- Deburr the cut edge immediately; fresh cut metal is genuinely sharp
- Wear eye protection: metal swarf and abrasive fragments are the classic eye injury
What goes wrong
- A wood blade in metal, which grabs and can shatter
- A coarse blade on thin sheet or tube
- Cutting galvanised or coated metal in an enclosed space; the fumes from hot zinc cause metal fume fever
Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.
Other blade questions
| For | Use |
|---|---|
| Tile | A continuous-rim diamond blade with water — and cut wet, because dry cutting tile produces respirable silica dust. |
| Wood | 24 teeth for ripping and framing, 40 for general work, 60-80 for a clean crosscut finish. |
| Plywood without tearout | A sharp 60-80 tooth blade, a scoring pass, tape on the line, and the good face oriented for the tool you are using. |
| Brick | A segmented-rim diamond blade, cut wet or with on-tool extraction — brick and mortar dust is a serious silica hazard. |
| Laminate | A triple-chip or negative-hook blade for worktops, and a reverse-tooth jigsaw blade for laminate flooring cut face up. |
| Acrylic | A triple-chip negative-hook blade on a table saw, or score-and-snap for thin sheet — and keep the feed steady so it does not melt. |
| Glass | None — a tungsten carbide scoring wheel, one firm pass with oil, then snap it. And toughened glass cannot be cut at all. |
| Plasterboard | A utility knife for straight cuts and a jab saw or multi-tool for cutouts — a circular saw is the wrong tool entirely. |
| Plastic pipe | A fine 24 TPI hacksaw or a proper pipe cutter — and deburr the inside afterwards, which is the step people skip. |
Common questions
- Which blade cuts metal?
- A bi-metal or carbide-tooth blade with at least three teeth in the cut — that tooth-count rule matters more than the machine.
- What should I avoid?
- A wood blade in metal, which grabs and can shatter A coarse blade on thin sheet or tube Cutting galvanised or coated metal in an enclosed space; the fumes from hot zinc cause metal fume fever
Related pages
- Which blade cuts tile? A continuous-rim diamond blade with water — and cut wet, because dry cutting tile produces respirable silica dust.
- Which circular saw blade for wood? 24 teeth for ripping and framing, 40 for general work, 60-80 for a clean crosscut finish.
- Which blade cuts plywood without tearout? A sharp 60-80 tooth blade, a scoring pass, tape on the line, and the good face oriented for the tool you are using.
- Which blade cuts brick? A segmented-rim diamond blade, cut wet or with on-tool extraction — brick and mortar dust is a serious silica hazard.
- Which blade cuts laminate? A triple-chip or negative-hook blade for worktops, and a reverse-tooth jigsaw blade for laminate flooring cut face up.
- Which blade cuts acrylic? A triple-chip negative-hook blade on a table saw, or score-and-snap for thin sheet — and keep the feed steady so it does not melt.
- Which blade cuts glass? None — a tungsten carbide scoring wheel, one firm pass with oil, then snap it. And toughened glass cannot be cut at all.
- Which blade cuts plasterboard? A utility knife for straight cuts and a jab saw or multi-tool for cutouts — a circular saw is the wrong tool entirely.
- Which blade cuts plastic pipe? A fine 24 TPI hacksaw or a proper pipe cutter — and deburr the inside afterwards, which is the step people skip.
- Which glue works on metal? Glue and adhesive
- Which drill bit should I use for metal? Drill bit
- Which paint should I use on metal? Paint
Sources
- Typical range compiled from manufacturer specifications — At One Place