This is a list of things you shouldn’t laser. It is not exhaustive; there are plenty of other things we can’t know whether you should laser cut. Do not consider this list to be exclusive in any way. If you don’t know what material something is, don’t cut it!
This is not a safety thread, don’t count on this thread to make critical judgments about your laser cutter or its operation. Additionally, this list is created by forum users without any sort of official company endorsement or support.
Fire and/or melting hazards
- Polystyrene foam: melts, catches fire. Reportedly #1 cause of laser cutter fires.
- Polypropylene foam: melts, catches fire.
- Thick ( > 1mm) polycarbonate / Lexan: cuts poorly, discolors, catches fire.
- ABS (acrylonitrile butadiene styrene): ABS does not cut well in a laser cutter. It tends to melt rather than vaporize, and has a higher chance of catching on fire and leaving behind melted gooey deposits on the vector cutting grid. With the right settings, it can be engraved - but take caution.
- HDPE (high-density polyethylene - like milk bottle plastic or those white cutting boards): catches fire, melts, turns gooey.
Health and laser hazards
- Any halogenated compound such chlorine (chloro-), bromine (bromo-), fluorine (fluoro-), etc: release acidic gases that can corrode your laser and endanger your health. Common compounds include PVC, also known as vinyl.
- Fiberglass: it’s a mix of two materials that can’t or shouldn’t be cut. Glass (which etches, but doesn’t cut) and epoxy resin (which causes dangerous fumes).
- Coated carbon fiber: emits noxious fumes. Thin carbon fiber mat can be cut, with fraying, but not the coated variety.