Clean DXF from AutoCAD, Fusion, SolidWorks and Inkscape: what breaks and how to export it

AutoCAD

• Visually closed is not closed: CypCut's manual warns that AutoCAD output can look like a closed contour and not be one. Join the outline (JOIN) before export, or let the importer close small gaps — Zorocut closes gaps up to 0.1 mm and reports every one it closed.
• Dimensions, title blocks and hatches are not geometry to cut. Zorocut skips TEXT, DIMENSION and HATCH entities, ignores layers whose names contain DIM, TEXT, TITLE, BORDER, HIDDEN, CENTER, DEFPOINTS or BEND, and lists what it skipped.
• Mirrored blocks: a block inserted with a negative scale stores its arcs with an extrusion of (0,0,−1). An importer that ignores it places those arcs mirrored and in the wrong spot — the classic “holes outside the part”. Zorocut transforms them correctly; if another program shows the symptom, explode the blocks first.

Fusion

• Export the flat pattern of the sheet-metal body as DXF. Fusion puts outer profiles, inner profiles, bend lines and text on separate layers; keep the bend lines out of the cut (Zorocut ignores layers whose names contain BEND).
• SendCutSend recommends Fusion's option to convert splines to polylines for compatibility. Zorocut reads splines either way and fits them with arcs and lines within 0.01 mm; arcs and circles stay true arcs.

SolidWorks

• Export a flat face or the sheet-metal flat pattern — not the whole part, and not a drawing view with its frame.
• Bend lines are optional in the export and drawn dashed: leave them off for a laser-only part, or keep them on their own layer.
• Export splines as splines; SendCutSend notes that curved faces can cause problems.

Inkscape

• Each Bézier segment becomes its own SPLINE, so a circle arrives as four separate splines that have to be joined end to end. Zorocut joins them; with “Flatten Béziers” on, the curve arrives as many tiny lines instead.
• A document in px is written with $INSUNITS = 0 at 96 px per inch: set the document unit to mm before exporting, or the parts come in 3.78× too big — see DXF units.
• Colours are reduced to six hues on export, so mapping processes by colour from an Inkscape file is coarse. Use layers.
• Convert text to paths before export (Path → Object to Path): text in a DXF is not cut.

Any CAD: the checklist

1. Only the part: no frame, title block or dimension on the cut layer.
2. Every outline closed; no duplicate or overlapping lines; no stray points.
3. Holes inside the outline. A shape inside a hole is read as a separate part.
4. A known unit, mm preferred.
5. ASCII DXF: Zorocut does not read binary DXF.