Which materials can you cut with a CO₂ laser, and what to avoid
A CO₂ laser will attempt to process almost anything you put in front of it. The machine cannot tell you that what it is cutting is producing a gas that will corrode it from the inside, or that will harm you.
Below is what is safe, what needs care, and what must never go in. If you do not know what a material is, establish that it is safe for the machine before you put it in. No fume is safe to breathe, so the machine and its extraction are what keep the fumes away from you. A material that corrodes the machine from the inside takes that protection away.
Never: do not put these in a laser
Section titled “Never: do not put these in a laser”| Material | Why not |
|---|---|
| PVC, vinyl, artificial leather, vinyl flooring and wall covering | Releases chlorine compounds. Corrodes the machine from the inside and is toxic to breathe. See the PVC article. |
| PTFE / Teflon | Releases fluorine compounds, the same class of problem as chlorine, with the same corrosion and health consequences. |
| Any chlorinated or brominated plastic | Same mechanism as PVC. Brominated flame retardants are common in electronics housings. |
| Anything with an unknown coating, laminate or adhesive | The base material may be fine and the coating may not. You cannot tell by looking. |
| Mirrored or bare reflective metal, without laser spray | The beam reflects straight back up the optical path and can destroy the laser source. Damage caused this way is not covered by warranty. See how to adjust for a material. |
Caution: possible, but with conditions
Section titled “Caution: possible, but with conditions”These are not banned, but they need extraction sized for the job, and some of them leave residue that takes longer to clean up than the job took to run.
| Material | What to watch for |
|---|---|
| Polycarbonate (PC, Lexan) in sheet | Absorbs poorly at the CO₂ wavelength, so it will not cut cleanly. It discolours, melts, catches fire easily and yellows the edge. Thin film is sometimes used deliberately for marking; sheet is not worth attempting. |
| MDF | Cuts and engraves well, but produces a great deal of smoke and a resinous residue that loads filters and settles on optics. Expect to clean the lens more often. On a recirculating extractor, cost the filters in before you start: MDF loads them quickly. |
| ABS | Melts rather than cuts, leaves a poor edge, and the fumes are harmful. Possible, but acrylic gives a better result on the same job. |
| Galvanised, zinc-plated or coated metal | Produces metal-oxide fumes. |
| Chrome-tanned leather | Contains chromium salts. Vegetable-tanned leather is the one to use for laser work, and it also engraves to a far better contrast. If the supplier cannot tell you which tanning process was used, treat it as unknown. |
| Fibreglass and carbon fibre | The resin binder burns and the fibres do not cut cleanly. Produces fine airborne particulate. |
| Flame-retardant treated stock | The treatment is often brominated. Ask what it is. |
| Anything food-related | Food can be laser processed safely, but BRM machines are not built to food-grade specifications and are not intended for it. |
Safe: the everyday working set
Section titled “Safe: the everyday working set”These are what a CO₂ laser is for, and they make up nearly all normal work:
- Acrylic (PMMA). Cuts with a polished edge and engraves to a clean frosted white.
- Wood and plywood. Cuts and engraves well. Quality and consistency vary a lot between suppliers.
- Paper, card and cardboard. Cut and engrave well; thin stock flares up easily.
- Vegetable-tanned leather. Cuts and engraves to a clean, high-contrast result.
- Textiles and felt. Natural fibres cut cleanly; check what synthetics actually are first.
- Cork, rubber (non-chlorinated), and most natural materials.
- Glass, ceramics and stone. For marking and engraving, not cutting.
- Metals. Only for marking, and only with a laser spray.
Starting settings for the common ones are in the example parameter tables.
How to identify an unknown material
Section titled “How to identify an unknown material”Most “is this safe?” questions come down to an unlabelled sheet someone was given. There is a reliable way to answer it, and it does not involve experimenting in the machine.
- Look for the recycling code. Code 3 is PVC. That is an immediate no.
- Read the label for the words PVC, vinyl, chlorinated, PTFE or Teflon. Anything described as a ‘forever chemical’ (PFAS) belongs in the same group.
- Ask the supplier for the safety data sheet. This is the definitive answer and suppliers are obliged to have one. It lists every component. Learning to read one takes ten minutes: what is an MSDS?
- If you cannot establish what it is, do not cut it. An unknown sheet is not worth a laser source, a set of optics, or your lungs.
Extraction is part of the answer, not a substitute for it
Section titled “Extraction is part of the answer, not a substitute for it”Everything in the “safe” column above still produces smoke and fumes that must be extracted away from you and away from the machine. Extraction makes safe materials workable; it does not make unsafe materials safe.
See laser fumes and why extraction is not optional.
On a BRM machine
Section titled “On a BRM machine”Safety data sheets for the materials and consumables we supply are under Downloads → MSDS, so anything that came with the machine is already documented.
Marking metal needs a laser spray, which we also supply: why use a laser spray.
Processing a chlorinated material voids the warranty on the machine, which is why the rule at the top of this page is absolute rather than advisory.
Still not sure?
Section titled “Still not sure?”If you have a material you want to process and cannot establish whether it is safe, ask us before you try it. Send the product name, the supplier, and a photograph of the label or the safety data sheet if you have one. We would far rather answer that question than quote for a new laser source.