Diode-Friendly Materials
A diode laser's success depends entirely on what absorbs 450nm blue light. Here's the working list, by absorption efficiency.
Engraves natively
| Material | Result | Notes |
|---|---|---|
| Birch / pine / hardwood | Brown burn, good contrast | The diode's strongest material. Mask with painter's tape. |
| Veg-tanned leather | Dark brown to black | Avoid chrome-tanned (toxic). |
| Dark slate / dark stone | White mark | Excellent contrast. |
| Cardstock / dark paper | Cut or score | Thin = cut, thick = engrave. |
| Cork | Dark burn | Watch for flare-up, keep air assist on. |
| Felt | Cut | Wool felt only; synthetic releases bad fumes. |
| Rubber stamp blanks | Engrave | Specialty laser-rubber gives clean stamps. |
Engraves with help (sprays / coatings)
| Material | Method | Result |
|---|---|---|
| Stainless steel | LBT-100 spray or dry moly (molybdenum disulfide) spray | Black bonded mark |
| Bare aluminum | CerMark / dry moly spray | Black bonded mark |
| Painted metal | Engrave the paint, expose substrate | White-on-color marks (depends on paint). |
| Anodized aluminum (dark) | Native | Bright white-on-black marks. |
| Powder-coated tumblers (dark) | Native | Ablate the coating like fiber/CO2. |
Won't engrave on a diode
- Bare polished metal (silver, brass, copper, mirror stainless), reflects 450nm.
- Clear acrylic, transparent at 450nm.
- White / light-colored materials, insufficient absorption.
- Glass, same; needs CO2 or fiber.
Starting settings (Lightburn, 20W diode, GCode controller)
Power is in % of max diode current. Speed in mm/min for diode (NOT mm/s like galvo).
| Material | Speed | Power | Passes |
|---|---|---|---|
| 3mm birch ply (cut) | 200 mm/min | 100% | 2-3 |
| 6mm birch ply (cut) | 120 mm/min | 100% | 4-6 |
| Wood engrave (raster) | 3000-5000 mm/min | 25-45% | 1 |
| Veg leather (engrave) | 3500 mm/min | 15-25% | 1 |
| Slate (engrave) | 2500 mm/min | 35% | 1 |
| Stainless w/ LBT-100 | 1500 mm/min | 90% | 1 |
| Cardstock 350gsm (cut) | 800 mm/min | 35% | 1 |
For per-material settings deep dives see the Materials section below. For broader laser principles that apply to all three types (fiber, CO2, diode), see the Foundations modules in the Fiber section.