LightBurn Material Library and Fill vs Line

LightBurn is the software we run in the shop, and two features do more daily work than almost anything else: the material library, and a clear choice between Fill and Line on each layer. Get those right, and you spend less time hunting for last week's settings and fewer jobs come off the bed with a cut layer that accidentally engraved, or a fill that tried to cut.

If you are still building a library, start with a test grid, as we describe in CO2 Laser Settings for Wood, Leather, and Acrylic. The library is only as good as the tests you put into it.

Why the LightBurn Material Library Saves Time

The material library is a saved list of presets you can apply to a layer. Instead of remembering that birch bag tags like a certain fill, and that the cut layer is a different speed and power, you store both under a name you will recognize later.

That matters in a busy shop. During ornament season we switch materials all day. A library keeps us from "close enough" guessing when we are tired. It also makes it easier for more than one person to run the machine without each job becoming a custom experiment.

Name presets clearly. "Wood" is not a name. "Birch 3mm, fill, Machine 1" is a name. Include the material, the thickness, the operation, and anything else that would change the result, like a mask or a specific machine.

How We Set Up a Material Library

After a test grid gives us a result we would actually ship, we use Create new from layer to save that layer into the library before we forget what we did. We keep cuts, scores, and fills as separate presets even when they are for the same material. They are different jobs, and they should not share a layer just because they share a species of wood.

To use a preset, select the layer in the Cuts / Layers Window, choose the preset, and click Assign or Link. Assign copies the settings onto the layer so you can still edit them. Link keeps the layer tied to the library entry, which means you cannot edit it in the Cut Settings Editor until you unlink it. When we apply a preset, we still glance at focus, air assist, and the lens. A perfect library entry will still fail on a dirty optic or an unlevel piece. The library remembers numbers. It does not inspect the machine.

If a material batch changes and the old preset is suddenly too hot or too weak, we run a small test, adjust, and save a new entry or update the old one with a note. We would rather have two honest presets than one leftover that is no longer true.

Fill vs Line in LightBurn

This is the distinction that new operators mix up the most.

Line follows the path. The beam traces the vector, which is what you want for a cut or a score. A cut-through uses enough energy, and often more than one pass, to separate the part. A score is a lighter line that marks the surface without cutting loose.

Fill is an engrave. LightBurn scans back and forth across the shape and fills it in, like coloring a shape with a very tight set of lines. Logos, text on a bag tag, and most artwork on wood or leather are fills. Interval, speed, and power all affect how dark and how deep that fill looks.

If you want the interior engraved and the outline traced on the same color layer, use Sub-Layers in the Cut Settings Editor: one sub-layer set to Fill and another set to Line, in the order you want them to run. LightBurn will show that layer as Multi in the Cuts / Layers Window. We use that carefully. Sometimes the outline is better as its own layer so you can give it different settings, or so you can run the fill first and the cut last. You may also see Offset Fill in the mode list; that is a contour-following fill, not a substitute for ordinary Fill or Line, and it is not the old Fill+Line mode.

Order matters. In almost every file, we engrave first and cut last. If you cut the part out first, it can shift, tip, or fall, and the fill will not land where the preview said it would.

Using Layers the Right Way

LightBurn's color layers in the Cuts / Layers Window are there so each operation can have its own mode and settings. A clean file often has a fill layer, a score layer, and a cut layer. You can put more than one operation on a single color with Sub-Layers, but separate layers are easier to see, test, and save in the material library. If a cut and an engrave share one layer with a single mode, they will get the same behavior.

When you import artwork, check what landed on each layer before you press start. It is common for a logo to come in as an outline when you wanted a fill, or for a cut to come in as a fill that will scan for a long time and never release the part.

Click a shape, look at the mode, and confirm: Fill for engraved areas, Line for cuts and scores. If a shape should be a solid engrave but is only a path, you may need to close it or set it to fill. If a cut is set to Fill, fix it before you waste a piece of material and a lot of time.

Common Fill and Line Mistakes

A few we still watch for:

• A cut layer left on Fill, which engraves a wide band instead of cutting out the part.

• A fill that is also set to Line, adding an unexpected outline or a second pass around every letter.

• Line Interval so wide that the engrave looks striped, or so tight that the job takes forever and overheats the material.

• On a GCode machine, Overscanning left off on a fast fill, which can darken or smear the edges. On a Ruida or other DSP controller, that switch will not be there because the controller handles overscan automatically. We cover that in LightBurn Overscan, Scan Offset, and Camera Alignment.

• The same library preset applied to a different thickness without a test.

None of this requires a special add-on. It is just a habit: test, save, name it well, and look at the mode column before every run. If you do that, Fill vs Line stops being confusing, and the material library starts paying you back on every job.