What does a laser cutting service do?
A laser cutter focuses a beam of light to cut through flat material, following a path from your file. It is quick, clean and good at fine, intricate shapes: small interlocking pieces, signs with detailed lettering, gaskets, model parts, cut-out gifts. There is no tool to wear down, and a new shape needs only a new file.
The same machine often engraves too, burning a design into the surface instead of cutting through. Many fabricators offer both. This guide is about cutting.
What materials can it cut?
The usual list is wood and plywood, acrylic, cardboard and paper, leather, felt and fabric. Some machines cut thin sheet metal, though that needs a different, more powerful kind of laser, so do not assume.
How thick it can cut depends on the machine and the material. A small desktop laser might cut a few millimetres of plywood and a thinner sheet of acrylic. A larger one cuts more. There is no one answer, which is why you should ask the fabricator and tell them the thickness you want.
Safety matters here. Some materials give off harmful fumes or damage the machine when a laser cuts them. Plastics containing chlorine, such as PVC and vinyl, are the well-known example. Never ask a fabricator to cut a material you cannot identify, and do not be offended if they decline. The fabricator decides what is safe to run on their machine. If you are unsure, tell them what the material is and where it came from.
What file should I send?
A laser follows lines, so it needs a vector file. A photo or a flat image does not work for cutting. Typical formats are:
- SVG, a common vector format that most design programs can export.
- DXF, the usual format from CAD programs and the safest for precise parts.
- AI or PDF files that contain vector paths. Ask first, because not every shop opens them.
Draw it at true size. Check the units. Cut lines are normally a hairline stroke with no fill, and the shop may ask you to use a particular colour for cuts and another for engraving. Convert text to outlines so that no font is missing when the shop opens the file. Remove duplicate lines too. Two lines on top of each other get cut twice, which scorches the edge.
If you have an idea but no file, you can ask the fabricator whether they draw designs. They may quote that separately.
What is kerf, and why does it matter?
Kerf is the width of the material the laser burns away. It is thin, a fraction of a millimetre, but it adds up. If you cut a hole and a peg to the same size, the peg ends up slightly small and the hole slightly large, so the fit is loose. For parts that slot together, the design needs a small allowance for the kerf. The right amount depends on the machine and the material, so ask the shop what they recommend instead of guessing.
What will the edges look like?
Expect some marks. A laser leaves a dark, slightly burnt edge on wood and leather, which some people like and some sand off. Plywood edges can show glue lines. Acrylic often cuts with a clean, polished-looking edge, though the paper film on the surface may need peeling and the face may carry some residue. Fabrics may have sealed edges, depending on the material.
Smoke can leave a sooty film on the top surface. Shops usually mask the sheet or wipe it afterwards. If appearance matters, say so, ask for a sample and ask what finishing is included.
What should I ask a fabricator?
- Can you cut this material at this thickness on your machine?
- What file formats do you accept, and do you check the file first?
- Can you supply the material, or do I bring my own? If you bring it, will you test it first?
- What will the edges look like, and what finishing is included?
- How do you handle the kerf for parts that fit together?
- How long, counting from the day I pay?
Ready to ask? Use the fabricator directory to find people who list laser cutting, and message two or three with the same file. To compare what they say, see custom parts made near me and how orders work. You can also browse the marketplace for designs a fabricator can cut for you.