Laser Cutting & Engraving
Settings, safety and alignment for diode and CO2 lasers, plus the box-making basics.
Safety & Materials
4 rules
Laser EverythingMaterial safety & SDS
Never laser an unknown or PVC/vinyl-containing material. Identify it, look up its CAS number, and read its Safety Data Sheet (SDS) for what it gives off when burned before the first job.
Laser EverythingRead an SDS for laser
Look up the material’s CAS number, use it to pull an SDS for the form closest to yours, and read sections 2, 5 and 10. Section 10’s hazardous decomposition products are the laser answer.
Laser EverythingCheck fume toxicity
Look up every decomposition product on the SDS in a toxicology source, then confirm the hazard in at least one more independent database before the material goes in the laser.
Laser EverythingPVC, ABS & acrylic
Never laser PVC or vinyl, don’t laser ABS, and cut acrylic only with extraction running and someone at the machine.
Dialing In Settings
10 rules
Make or Break ShopSpeed / power test
For a new material, run a speed-vs-power test grid on a scrap of the real stock, fastest speeds first, and read the best cell straight off the sheet.
The Crawlspace CraftsmanMax power in LightBurn
Make LightBurn’s S-value max (Device Settings) equal the controller’s max spindle speed ($30 in GRBL) so 100% power in software is 100% at the laser.
Steve Makes EverythingSettings library
Run one focused material test to find good settings, then save them as a named material entry — build a library so each material is dialed in once, not re-guessed every job.
Laser EverythingGalvo timing & delays
With jump delay parked at 500/500/500, mark a hatched box at Start TC values from +1000 to −1000 µs, pick the value where lines meet the contour without a burn, then repeat for Laser Off TC.
Make or Break ShopDithering for photos
Find a photo speed and power in Jarvis or grayscale first, then engrave the same image in every dithering mode at that one setting and pick by eye.
Make or Break ShopLines per cm (DPI)
Start vector engraves at 100 lines/cm and test photos from 100 to 300 lines/cm on the real material; the best result is often below your machine’s maximum.
Maintenance & Alignment
4 rules
Edmonds WoodshopBeam alignment
Align one mirror at a time, in beam order: pulse a tape target at the near and far end of travel, and adjust the mirror before the target until both marks land on the same spot.
Steve Makes EverythingMachine maintenance
Clean on a fixed calendar, not when cuts get bad: optics, bed, rails, fans and exhaust on a routine, and the coolant changed every month or two.
Steve Makes EverythingClean the optics
Wipe the lens and mirrors lightly with lens wipes or 99% isopropyl alcohol, starting at the lens and working back up the beam path, then dry so nothing re-deposits.
Steve Makes EverythingCoolant change
Replace the coolant every 1–2 months with distilled water; add 20–50% propylene glycol if the shop can freeze, and run the pump until no air bubbles remain in the tube.
Setup & Workflow
4 rules
Laser 101Placement outline
Burn the blank’s outline onto a scrap sheet on its own layer, set each blank on that outline, then run only the design. Don’t move the scrap or the origin between runs.
Computer CreationzRepeatable jigs
Cut a pocket jig on the laser at the product’s measured size, add a finger notch to each pocket, array as many as the bed holds, and keep the design simple.
Computer CreationzJig template
Once the jig is cut and fits, duplicate the layout, convert the copy entirely to a tool layer so none of it can reach the laser, and save it in LightBurn’s Art Library.
Computer CreationzJig alignment targets
Engrave dot-sized targets near the jig’s corners, run in absolute coordinates, drive the laser to one target and set it, then swing the jig until the opposite target lines up.