Layered SVGs for Laser Cutting & Engraving
Lasers do three things: cut through, score with a light pass, and raster (burn the surface like an inkless printer). A typical job mixes all three. The fastest way to set that up is not hand-selecting dozens of paths in LightBurn. It is a source SVG whose colors already encode the operations. This guide shows how to produce exactly that file from a raster image, free.
Why layers map so cleanly onto laser operations
Every serious laser driver (LightBurn, XCS, xTool's suite, Glowforge's importers) lets you assign settings (power, speed, number of passes) per layer, which in practice means per fill color. That behavior is a direct invitation: draw one color per operation and the software builds most of the job for you. A traced SVG is exactly a stack of one color per layer, so the trick becomes controlling which colors exist in the file.
Two features make that control practical from a raster starting point. First, merge: pick source colors and fold them into one target color, rebuilding the file with everything on one layer. Second, per-layer download: every color exports as its own separate SVG at identical dimensions: one file per operation role, so the software's job settings screen stays a list of meaningful layers instead of 40 anonymous paths.
The "operation palette" workflow
Think of colors as a vocabulary with three roles. Put the whole job in one palette before downloading:
- Cut: the through-line color (commonly red, since LightBurn defaults cut to it): outlines of the finished part, notches, registration marks.
- Score: a mid-tone color for engrave-as-line operations: fold lines, engraved text set as strokes, decorative outlines you want visible but not cutting.
- Raster: a dark fill color for anything engraved as area: logos, names, filled icons.
From your traced result, merge every color into one of those three targets (including the custom-color picker for your machine's exact convention), hide any layer that should not exist, then download either the merged single file or per-layer files. In LightBurn, import, run one setting pass per layer in the Cut Settings editor, and the job is authored.
Material notes: why edge quality matters to the beam too
It is tempting to assume edge smoothness only matters for blades. It matters for beams as well: a raster pass burns an outline that wobbles with every staircase pixel at speed; a cut pass with path segments measured in fractions of a millimeter both slows the job and burns micro-blips visible against backlight on wood and acrylic. Tracing with a competent Simplify value gives the motion planner long, tangent-continuous curves, so the head accelerates smoothly, so visibly cleaner corners and faster raster passes on the same artwork.
For acrylic in particular, cut edges at high Simplify are cleaner to flame polish. For wood engraving, the posterization step (few flat colors instead of noisy gradient bands) produces more even raster power density, which is the same quantize-then-posterize pipeline graph artists use deliberately for editorial illustration.
Practical parameter starting points
- Detail: 1024px is a good default for logos; push 1536px for fine faces and intricate crests. Small images that arrive pixelated benefit hugely from up-front Detail so the tracer sees real pixels.
- Colors: start at 4–6 for material art, then merge into the operation roles above. More than ~8 distinct colors on one raster source is usually material for merge, not for more vinyl-like separation.
- Simplify: raise until the after-preview at 400–800% zoom shows consistently smooth curves without collapsing letters' counters.
- Knockout: hold-to-compare and the knockout click removes colors you want as "no-op" (backgrounds you will not raster).
A caution for production: run one material test first at the corner of the sheet with each operation color present, and only scale up after the burn matches expectation. Every laser, lens, and wood batch differs, and the SVG changes settings not physics.
The takeaway
Layered, per-color SVGs transform laser work from path janitorial work into color semantics: cut is one file or one layer, score another, raster a dark fill. Same geometry for both split and merged download, exact registration between layers by construction, and the whole job authored in the machine's native settings UI. Try it on a logo you have on hand: the converter runs entirely in your browser, each layer downloads separately, and nothing gets uploaded anywhere along the way. Related reading: the vinyl preparation guide covers the analogous cut-file logic for plotters.