Laser 101: FAQs & Tips for Laser Cutting
New to laser cutting? Start here. We explain the basics—how CO₂ lasers cut and engrave, which materials are safe, and how to set up your file. You’ll learn the difference between cutting and engraving, why vector files matter, and simple ways to avoid burn marks or rough edges. We also cover safety, ventilation, and tips for better results. Whether you plan to rent a laser or have us do the work, this quick guide will help you make confident choices and get cleaner parts.
FAQs
- Cutting vs. engraving—what’s the difference?
Cutting goes through the material; engraving marks the surface. - Which materials are safe to cut?
Common options include acrylic, wood, cardboard, some fabrics, and other laser-safe materials. Avoid PVC and unknown plastics. - Why won’t JPEG or PNG work for cutting?
They don’t contain paths. Laser cutters need vector files like AI, DXF, or PDF. - What software should I use?
Illustrator or LightBurn are common choices. Export clean vectors at the correct scale. - Any quick tips for cleaner results?
Use the right material, nest parts to save stock, keep optics clean, and choose sensible power/speed settings.
Understanding Kerf: How to Account for Material Loss
Kerf is one of the most important concepts in laser cutting, and understanding it will save you frustration and failed parts. Kerf is the width of material that the laser removes as it cuts—typically 0.003" to 0.005" depending on material, focus, and laser settings. For most projects, kerf is negligible. But for precise assemblies or fitted parts, accounting for kerf is essential.
What Is Kerf Exactly?
The laser beam has finite width. As it follows a cut path, it removes material from both sides of the path. This removed material is kerf. For a 0.004" kerf on a cut, the total material removed is 0.004", but it's distributed across both sides of the path (0.002" on each side). Understanding this distribution helps you design accurately.
When Kerf Matters
For simple cuts or engravings, kerf is invisible—you'll never notice it. But if you're designing interlocking parts, dovetail joints, or pieces that need to fit together precisely, kerf affects dimensions. If you design a slot to be exactly 0.250" and kerf removes 0.004", the actual slot opening will be 0.246"—half a kerf on each side. If a tab is designed to be 0.250" and kerf removes 0.004", the tab will be 0.254" (kerf adds to each side). Parts won't fit as intended.
How to Account for Kerf
There are two approaches. First, test on prototype material with your specific laser and settings. Cut a few test pieces and measure. If you discover a kerf of 0.004", you now know how to adjust your design. Second, ask your laser shop upfront what their typical kerf is for your material and thickness. They can tell you and suggest design adjustments.
Kerf Direction Matters
When kerf is removed, does it come off the inside of your intended cut or the outside? For slots that something will fit into, kerf makes the slot slightly narrower. For tabs that fit into slots, kerf makes tabs slightly wider. Designing with this in mind prevents fits that are too tight or too loose.
Testing and Refinement
Always test fit before full production on precision work. Cut one set of parts and verify they fit as intended. Tolerance issues reveal themselves immediately. Once you've confirmed fit, you can confidently move to full production knowing parts will fit correctly.
Designing precision laser-cut parts? American Laser Cutter can advise on kerf accounting and help you achieve proper fits. Visit americanlaserco.com to discuss your specifications.
LASER CUTTING RESOURCES
This website is fantastic to pick up parts for your laser cutter.
This is a fantastic replacement software for laser cutters
https://lightburnsoftware.com/
This is a link to RdWorks software
https://www.ruidacontroller.com/download/
rescue files for RDworks and lightburn (still adding files)