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Advanced TechniquesModule 5.1~3 min read

Inlay Technique

Cut a pocket in one wood, cut a matching shape in a contrasting wood, glue the inlay into the pocket. The trick is kerf compensation, the laser removes ~0.1-0.2mm of material per cut, so pockets and inlays must be sized opposite directions to fit cleanly.

The problem with naive inlay

If you cut a circle pocket in maple and a circle inlay in walnut at the same dimensions, the inlay won't fit. Each cut burned away a slot about 0.1mm wide, centered on the path: 0.05mm off each side. The pocket is now 0.1mm larger than design and the inlay is 0.1mm smaller. Net mismatch: 0.2mm. The inlay floats in the pocket with a visible gap.

Kerf compensation: the fix

In Lightburn → Cut Settings → Kerf Offset:

  • Pocket layer: Kerf Offset = -0.05 mm (path moves inward, so the burn widens the hole back out to the design line).
  • Inlay layer: Kerf Offset = +0.05 mm (path moves outward, so the burn trims the piece back down to the design line).
  • Each offset is half the kerf. In LightBurn a positive Kerf Offset moves a path outward and a negative one moves it inward. Adjust based on your kerf width (varies by material thickness, beam diameter, lens).
KERF: WHAT THE BEAM REMOVESthe line you drewkerf, about0.1 mm wideThe beam burns a slot centered onyour line. Half the kerf comesoff each side of it.NO OFFSET: A LOOSE FITPOCKETINLAYhole too bigpart too smallDashed = your design, red = burnedaway. Both edges miss it: a gap.HALF-KERF OFFSET: A TIGHT FITPOCKETINLAYpath moved inpath moved outShift each path by half the kerf andboth edges land on the design line.
Kerf is exaggerated here so you can see it. On real wood it is about a tenth of a millimeter, which is still enough to make an uncompensated inlay rattle.

Calibrate your kerf for inlay

  1. Cut a single straight line in scrap of your target wood at production settings.
  2. Inspect under a loupe + caliper. Measure the actual kerf width.
  3. Halve that number, that's your per-side kerf offset.
  4. Apply it as a negative offset on the pocket layer and a positive offset on the inlay layer.

Inlay workflow

  1. Design the inlay shape in Lightburn or vector software.
  2. Create two layers from the same vector: Pocket (kerf -0.05mm) and Inlay (kerf +0.05mm).
  3. Run pocket cut on the host material (e.g., maple plank).
  4. Run inlay cut on the contrast material (e.g., walnut sheet).
  5. Test fit. Adjust kerf offset if too loose or too tight.
  6. Glue inlay into pocket using Titebond III or similar wood glue.
  7. Clamp 30 minutes. Sand flush after dry.

Common inlay pairings

  • Walnut on maple: classic; high contrast.
  • Padauk on poplar: orange/red on cream.
  • Ebony on birch: black on light, premium look.
  • Wenge on cherry: dark brown on warm red.
  • Sapele on maple: rich red-brown on cream.

Multi-color inlay

Three or more colors? Run each as its own layer with its own kerf offset:

  • Maple base = pocket only (no kerf compensation, single material).
  • Each contrast piece = its own inlay layer with -0.05mm kerf.
  • Plan the cut order so larger pieces glue first, smaller pieces fill gaps.

Engraved + inlaid combo

For ultra-clean designs: pocket + inlay PLUS engraved detail on top of the inlay. Workflow:

  1. Cut pocket on host.
  2. Cut inlay on contrast material.
  3. Glue + clamp + sand flush.
  4. Re-mount the assembled piece on the laser.
  5. Engrave details across the assembled surface (text on the inlay, decorative lines crossing both materials).

Marquetry: advanced inlay

Multi-piece intricate veneer-based inlay. Same principle but using paper-backed wood veneers (~0.5mm thick) instead of solid stock. Allows highly detailed inlays without deep glue lines.

Common pitfalls

  • Inlay falls through. Kerf compensation too aggressive. Reduce by 0.025mm and re-test.
  • Inlay won't fit. Kerf compensation insufficient. Increase by 0.025mm and re-test.
  • Visible gap on one side after gluing. Inlay shifted during clamping. Use a shim or weight to keep aligned.
  • Burn marks on inlay edges. Cut speed too slow. Increase speed slightly.
  • Pocket bottom is rough. Multi-pass cut with reducing power on each pass for cleaner floor.

For deeper relief work pairing engraving + inlay. See CO2 Deep Engraving, Wood & Acrylic. The inlay technique combined with grayscale relief produces some of the most premium custom wood pieces possible on a CO2.