Reading the check

The build produced no layers at all. Almost always the mask is empty or nearly empty — a picture that came out mostly white, or a cleanup that removed everything.

Go back to the mask and check it looks like a stencil: solid black shapes on white. If it does not, cleaning the artwork is where to start.

A layer does not share the master bounding box, so stacking the sheets at the same origin would not align them. Everything downstream of this — the fit, the shadows, the glue-up — depends on every sheet being the same size and in the same place.

Rebuild the layers. If it survives a rebuild, the mask is the likely cause; a shape that extends past the edge of the image can move the box on one layer only.

One sheet does not carry the master outline. The message names the master ring's length and area and how far the closest ring on this layer is from it, so a small number means a near miss and a large one means a different shape entirely.

Usually fixed by choosing the Frame border with a Frame width, which gives every sheet the same frame regardless of what the artwork does near the edge.

Layer 1 is set to be a solid backer and something has cut through it. The message counts the cuts. A backer with holes in it stops being the thing the rest of the stack is glued to, and light comes through the back of the piece.

Check Bottom layer. It is Solid silhouette unless you changed it; if you meant the back to be open, set it to As the step leaves it and this stops being an error.

A layer is missing a feature that the layer below it has, and the message names them. The stack is cumulative by design — every layer cuts away everything the layers under it cut away, plus its own — so a feature that vanishes and reappears is a hole in that rule and reads as a machining mistake in the finished piece.

Rebuild the layers. This one should not survive a rebuild; if it does, it is a bug worth writing in about.

The top sheet does not carry every feature you approved, and the message lists the first few. The top layer is the one that shows the whole design, so anything missing there is missing from the piece.

Rebuild. If specific features keep dropping out, they are probably below the minimum size for your material and are being simplified away — see your material.

Part of the design has escaped the outer edge. On the machine that is a cut running off the panel and into whatever is under it.

Every sheet is cut out of the same outline, so this should not survive a rebuild. Rebuild the layers; if it is still there, it is a bug worth writing in about, with the project attached.

A shape crosses itself, or is not closed, or is otherwise not a valid area. Cutter software either refuses these or does something unpredictable with them.

Rebuild the layers. If it survives that, the mask needs cleaning — see cleaning the artwork.

A strand of material measures less than your Min bridge width, and the measurement is confident. The message gives both numbers, and the finding shows measured and required under it. Thin strands are where a piece snaps, either on the bed or in your hands afterwards, which is why this one fails the check rather than warning. However big the piece, a strand far finer than the minimum - narrower than the laser's beam, even, which would burn it away and join the openings either side - is found and measured on the outlines themselves, so a large Finished size never hides one.

It is the one error measured against a number you chose, so there is more than one way out. Before reporting it the build has already widened every thin strand it could by trimming the cuts beside it; what is left is where widening would have eaten into the design. From there, lower Min bridge width if you know your machine and material hold that width; make the piece bigger with Finished size, since every strand scales with it and rebuilding at a new size is free; or generate the picture again at a lower Detail level, or with a style note asking for thicker lines.

If most of the sheet is under the minimum - a drawing made of lines, with Invert on so the lines are the wood - the studio says so in the build notes and leaves the lines as drawn rather than trying to widen every one of them: line-work cannot be brought up to the minimum without redrawing it. The note says how much larger to cut the piece for the lines to clear the minimum, or lower Min bridge width to what your material holds.

The exported file contains an element — the message names which — that LightBurn and most other cutter software cannot treat as cut geometry. Text and groups with effects are the usual ones.

Export again. If it repeats, send us the file; the exporter should never produce this.

A sheet came out with a raster image inside it rather than vector outlines. A laser can engrave a raster; it cannot cut one. The piece would come out scorched rather than cut through.

Export again, and write in if it repeats.

The SVG uses greys the export should not produce. Cutter software maps colour to operation — a grey line is usually read as engrave rather than cut — so a stray colour silently changes what the machine does with that path.

Export again. This is ours to fix if it repeats.

The exported files do not share a width, height and viewBox, so opening them together puts them at different scales or positions. The message counts how many different combinations came out.

Export the whole set again rather than reusing files from an earlier export — a folder holding sheets from two different builds is the common cause.

The same measurement as thin_bridge, but close enough to the limit that the studio will not swear to it — the message says "about" rather than giving a firm figure. It is a warning rather than an error, and reported separately, so that a genuinely thin strand is not lost in a list of maybes.

Worth looking at on the canvas. Marginal on a good machine, a break on a tired one.

A shape narrows to a tip thinner than your Min bridge width. Points char first and chip easily, so a design full of them looks crisp on screen and rounded in wood. A point is supported along its whole length, so it cuts; it is the tip that suffers when you handle or sand the piece.

Usually accept it — a slightly blunted point is not usually what somebody notices about a finished piece. A bigger Finished size makes every point broader, and a lower Min bridge width tells the check your material holds a finer one.

A slot is thinner than your Min cutout width. Below that width the char from both sides meets in the middle and the slot stops reading as a hole — it comes out as a dark line.

On the sheets below the top most of these are made by the Layer step, which pulls every opening in, so a smaller step leaves them wider. The build already closes any opening that is narrower than Min cutout width all the way across; what is reported here is an opening that is only narrow in part. Lower Min cutout width if your machine cuts finer than you told it, or make the piece bigger with Finished size.

An opening too small to cut cleanly: under half the square of your Min cutout width in area, which is 0.72 mm² at the default 1.2 mm. The message gives its area. This is often not artwork at all but a speck of dust in a scan or a stray pixel from a generated image.

On the Clean Artwork step, raise Min hole area a little; it fills pinholes smaller than it in the mask, and it is 0 by default. The mask cleans itself again, and you build again, which is free. Raising Min cutout width also has the build close more of the smallest openings.

A piece of material smaller in area than a circle as wide as your Min feature size — about 0.2 mm² at the default 0.5 mm, 7 mm² at 3 mm. The message names both the piece and the minimum, and the minimum comes from the material panel rather than from anything universal.

Fine in a design where you will not miss it. Not fine if it is the centre of the piece. Raise Min feature size and rebuild to have the build cut more of the smallest pieces away, or lower it if your material holds pieces that small and you want the warning gone. See Min feature size for exactly what it removes.

Part of a layer is a separate island of material with nothing joining it to the body of the sheet. It will drop out when the cut finishes.

Whether this is an error or a warning depends on your Island policy. Under Allow separate piece it is a warning, and the message says the piece is expected: you asked for loose pieces to glue back by hand. Under any other policy it is an error and the stack does not pass, because the studio meant to hold that piece and could not find a tab that would.

If the piece is an island in the artwork — the middle of an O, a dot inside an opening — tick islands (N) above the canvas and it has a square marker; clicking it removes the island, so its opening is cut as one shape with nothing inside and nothing is left to fall out. Or set Island policy to Allow separate piece if you are happy to glue it in. Either way, press Rebuild Layers afterwards — see the Layer Editor. Redrawing that part of the artwork so it touches something is the other fix.

The studio proposed a bridge to hold this piece in place, you refused it, and the piece is consequently loose. It will be cut free and has to be glued back by hand.

Deliberate, if you refused the bridge on purpose — some pieces look better without a visible strap. Otherwise click the grey tab marker again to take the refusal back, or use restore N refused above the canvas to put every refused tab back, and rebuild. A lower Min bridge width allows a thinner, less visible tab.

Two sheets cut so similarly that the step between them will not read, and the message gives the two figures in millimetres of internal cutting. In the worst case — when no layer opens up further than the backer — the stack has no depth at all.

Use fewer layers, or raise Layer step. Artwork with larger openings also fixes it: a design of fine, even detail has nothing to reveal gradually.

Two nearly identical contours sit on top of each other. The machine has no way to know they are the same line, so it cuts it twice: double the char on that edge, double the time, and on thin material a second pass can widen the kerf enough that a piece which should have stayed put drops through.

Rebuild the layers — this is almost always something in the mask rather than something you asked for, usually a shape traced twice in the source artwork. If it survives a rebuild, send us the project and we will look at it.

The SVG has paths whose ends do not quite meet, and the message counts them. A cut path is meant to be a closed loop: that is what tells the software which side is the piece and which side is waste.

Most cutter software cuts an open path anyway, so this is a warning rather than an error. What misbehaves is anything that needs an inside and an outside — kerf offset, fill, and the tab or bridge tools — which may silently do nothing on that path or apply themselves to the wrong side of it.

Export again. Persistent open paths are a bug at our end and worth telling us about, with the project attached.

A sheet carries a transform rather than having its coordinates flattened. Software that honours it opens the file correctly; software that ignores it opens the sheet at the wrong place or scale.

Export again, and check the sheets line up in your cutter software before running the job.