What Materials Does a Fab Lab Stock?
The short answer
Fab labs stock a deliberately short list of materials, chosen because the machines in the room process them repeatably: sheet goods for the laser and the router, filament for the 3D printers, copper-clad board and machinable wax for the small mill, and rolls of adhesive vinyl. The machine classes that drive those choices come from the standard lab inventory (Fab Foundation getting-started material). What a lab refuses to stock matters just as much, and that list is mostly about fumes.
Laser materials
The laser is the workhorse, and its material list is narrow on purpose:
- Acrylic, usually in nominal thicknesses from about 1/8 to 1/4 in (3 to 6 mm). Cast acrylic frosts to a matte edge when engraved; extruded acrylic cuts cleanly and polishes glossy. Labs often stock both and label them.
- Plywood and MDF, cheap and good for jigs, enclosures, and press-fit assemblies. Both char at the edge, and plywood voids can stall a cut.
- Cardboard and chipboard, the standard prototyping material because iterating costs nothing.
- Paper, mat board, felt, and leather for smaller or decorative work, where power settings matter more than thickness.
The hard limits are thickness and fume chemistry. Chlorinated plastics such as PVC are commonly banned outright from laser cutters because of what they release when vaporized, and university environmental health and safety offices treat beam exposure, fire risk, and fume and particulate ventilation as the three controlling hazards of these machines (University of Washington EH&S laser cutter guidance). That is why a lab will ask what your material is before it will ask what your file is. Machine-side specifics are in what specs matter on a fab lab laser cutter.
Router materials
The large CNC router eats what the laser cannot: thick plywood, MDF, OSB, solid hardwood, rigid insulation foam for molds and shaping, and sheet plastics such as HDPE. Some labs run aluminum with the right tooling and a slow, shallow strategy; many do not allow it at all. Foam and MDF both generate large volumes of fine dust, which is the real reason extraction is non-negotiable on this machine.
3D printing materials
Filament printers mostly run PLA as the default, with PETG where a part needs more toughness, ABS where heat resistance matters, and TPU for flexible parts. Resin printers use photopolymer resins, which bring uncured-liquid handling into the picture and are usually kept to a dedicated bench.
Printing is not a fume-free process. State and university guidance treats printer emissions, enclosure, and room ventilation as the design questions for schools and shared spaces (Washington State Department of Health, 3D printers; Kansas State University 3D printing safety). In practice this shows up as rules about which materials may run in which room, and how a lab handles the training and sign-off around them, described in makerspace equipment training and access.
Small-mill materials
The desktop precision mill has the shortest list of all:
- Copper-clad board, where labs commonly prefer paper-based FR-1 over fiberglass FR-4, because milling fiberglass produces abrasive glass dust that is unpleasant to breathe and hard on tiny cutters.
- Machinable wax, for small molds and for proving a toolpath before committing to stock.
- Soft plastics such as acetal or HDPE for small mechanical parts.
Why nominal thickness is a running annoyance
Press-fit design assumes the slot matches the sheet. It usually does not: nominal 1/4 in plywood is rarely 0.250 in, and it varies across a single sheet. Experienced users measure actual stock with calipers, then cut a small test comb of slots at several widths before running the real job. Kerf compensation is the same story on the router, where the effective cut width is the cutter diameter plus whatever deflection the machine contributes.
How labs handle supply and cost
Most labs sell common stock at cost or near it, let you bring your own material subject to an approval rule, and charge separately for consumables such as cutter bits and filament. Prices shift constantly, so ask the lab rather than trusting a number you read somewhere. For how material and consumable costs sit inside a budget, see what it costs to start a small makerspace, and for the machines those materials feed, what equipment a standard fab lab has.