Vector Files for Laser Cutting and Engraving: A Beginner’s Guide

Cutting & CraftsBy the Vectorizo team · November 8, 20264 min read

Learn how laser software reads a vector file: cut, score and engrave, why closed shapes matter, how colors map to layers, how to avoid double cuts, and how to prepare an SVG for LightBurn, Glowforge or xTool.

A laser cutter or engraver is one of the most rewarding tools a maker can own, but it is also unforgiving: the laser follows the lines in your file exactly. A clean vector file gives you crisp cuts and sharp engraving. A messy one wastes material, doubles your cutting time or burns lines where you did not want them. This guide explains how laser software understands a vector file and how to prepare one.

Cut, score and engrave

Laser software treats a design in one of three ways:

Cut: the laser follows a line at high power and goes all the way through the material.
Score (or line engrave): the laser follows a line at low power, marking the surface without cutting through.
Engrave (or fill): the laser moves back and forth like a printer, burning the whole inside of a shape.

Vector files are needed for cutting and scoring, because the laser must know the exact path to follow. Engraving can use either vectors or a raster image, but vector shapes give the sharpest edges.

Why vector, and why closed shapes

A vector file describes each shape as a path. For cutting, every outline you want cut out must be a closed path: the line must end exactly where it started. An open path leaves a gap, and the piece will not drop out of the sheet. For fill engraving, closed shapes are also needed, because software can only fill an area that has an inside and an outside.

Traced SVGs are made of closed, filled shapes, so they work well for both cutting outlines and fill engraving.

Colors become layers

Most laser programs, including LightBurn, Glowforge and xTool Creative Space, sort a design into layers by color. You then choose what each color does.

A common setup:

red lines for cuts;
blue lines for scoring;
black fills for engraving.

The colors themselves do not matter to the machine; they are just labels. What matters is that each operation has its own color, so you can give it the right speed and power. When you vectorize artwork for laser work, keeping the number of colors small makes this step simple.

Importing an SVG into LightBurn

Use File → Import and select your SVG.
LightBurn creates one layer per color in the Cuts / Layers panel.
For each layer, choose the mode: Line to cut or score along the outlines, Fill to engrave the inside of shapes.
Set speed and power for your material, then use the preview to check the path before you run the job.

Glowforge and xTool work in a similar way: upload the SVG, then assign Cut, Score or Engrave to each color.

The double-line problem

Here is a mistake almost everyone makes once. A thin line in a picture — the outline of a cartoon, a border, a letter stroke — becomes, after tracing, a thin filled shape with an inner and an outer edge. If you set it to Line (cut), the laser cuts both edges: two parallel cuts a fraction of a millimetre apart, and the thin strip between them falls out or burns.

Ways to avoid it:

set that layer to Fill so it is engraved as a solid line instead of cut;
for cutting, keep only the outer outline of a shape;
in a vector editor, replace the thin shape with a single centre line (a stroke).

Size, units and kerf

Check the size after import. Programs interpret SVG units differently. Measure a known dimension and scale if needed.
Kerf is the width of material the laser burns away, typically a fraction of a millimetre. For boxes, inlays and puzzles that must fit tightly, compensate with your software's kerf offset setting.
Minimum detail: very small holes and thin bridges can burn away or warp. As a rough rule, keep parts of thin wood at least a few times thicker than the kerf.

Preparing artwork for engraving

Use flat, solid colors. Soft shading does not translate into vector fill engraving; it becomes either solid or nothing.
For a photo engraving, use a raster image with dithering in the laser software instead of a vector.
For logos and text, vectors give clean edges. Convert text to paths so missing fonts do not change the look.
Remove the background shape so the laser does not engrave a big rectangle.

A simple workflow from image to laser

Start from the largest, cleanest image you have.
Convert it to SVG with a vectorizer such as Vectorizo. For one-color designs choose Artwork "Silhouette (2 colours)" or "Line art"; set Background to "Remove".
Open the SVG in your laser software and check the size.
Assign each color to cut, score or engrave.
Run a small test on a scrap of the same material.

Common problems

The piece does not fall out: the path is open, or the cut did not go through. Check closed paths and increase power or passes.
Engraving looks jagged: the source image was low resolution; trace a larger copy.
Job takes forever: too many tiny shapes or nodes. Simplify the vector, reduce Detail and merge shapes.
Unexpected rectangle engraved: a background shape is still in the file. Delete it.

Summary

Laser software reads vector shapes as paths to cut, score or fill. Keep shapes closed, colors few and meaningful, backgrounds removed and thin lines engraved rather than cut. With a clean SVG and a quick test on scrap, your first cut is far more likely to be your best one.