How to export a DXF for cutting

A clean DXF for cutting, in six checks

1. Draw the part at full size, 1:1, in inches or millimeters.
2. Export only the flat outline and its holes, as closed shapes. No open ends, no duplicate or overlapping lines.
3. Leave out dimensions, notes, the title block and the border.
4. Turn text into outlines if it is meant to be cut or etched.
5. Keep it flat: 2D, on the XY plane.
6. Save one part per file, and give the quantity separately.

Autodesk Fusion

From a sketch:

1. In the Browser, right-click the sketch and choose Export DXF.
2. Pick the units (they start as the design's units).
3. Leave points, projected geometry and construction geometry off unless they should be cut.
4. Click OK and save.

From a sheet metal part:

1. In the Browser, right-click the flat pattern and choose Activate.
2. Click Export DXF on the toolbar and pick the units.
3. Tick Convert Splines to Polylines if the cutting software does not take splines.
4. Leave bend lines off unless they should be etched; Fusion puts outer profiles, holes, bend lines and text on separate layers.

SolidWorks

1. For sheet metal, right-click Flat-Pattern in the FeatureManager tree and choose Export to DXF/DWG. For any flat part, select the planar face, right-click it and choose Export to DXF/DWG. SolidWorks sets what it exports from where you started.
2. In the DXF/DWG Output panel, clear Bend lines and anything else that should not be cut.
3. Use the cleanup preview to remove anything that is not part of the cut.
4. In the system options for DXF/DWG export (Tools > Options > Export) you can save splines as polylines and merge end points that nearly touch.

AutoCAD

1. Delete or turn off dimensions, notes and the title block, or use Save As > Tools > Options > DXF Options > Select objects to export only the part.
2. File > Save As, and in Files of type choose a DXF version.
3. Save as ASCII (the default), which more programs read than binary DXF.

AutoCAD saves the drawing's units in the DXF (the INSUNITS setting: 1 for inches, 4 for millimeters, 0 for unspecified). Set it before saving so the file says what it is.

Autodesk Inventor

1. In the Browser, right-click the flat pattern and choose Save Copy As, with the type set to DXF.
2. In the export options, pick the DXF version and turn off layers you do not want cut, such as bend lines.
3. Or right-click a planar face and choose Export Face As, which writes the outer profile as a polyline.

Onshape

1. Right-click the face, or the flat pattern of a sheet metal part, and choose Export as DXF/DWG.
2. Choose DXF and a version.
3. Tick Export splines as polylines if the cutting software needs it.

Exporting a planar face gives only its outer outline, so holes can be left out. For a part with holes, export a sketch of the whole profile or the sheet metal flat pattern instead, and check the file. Onshape exports sketches in the document's default units.

FreeCAD, Inkscape, Illustrator and SketchUp

• FreeCAD: for a 3D part, make a flat projection first with Draft > Modification > Shape 2D view, then select it and use File > Export and choose DXF. Its DXF preferences can write splines and ellipses as polylines.
• Inkscape: set the document units to inches or millimeters, convert objects and text to paths, then Save As > Desktop Cutting Plotter (AutoCAD DXF R14). A document in pixels exports without units.
• Adobe Illustrator: File > Export > Export As > AutoCAD Interchange File (DXF), and set the scale units so a drawn inch exports as an inch.
• SketchUp (desktop): use a standard view with Parallel Projection, then File > Export > 2D Graphic as DXF, keeping Full Scale in the options.

Units, splines and 3D files

A DXF's numbers have no units of their own; the file says what they are in a header setting, INSUNITS, if the program wrote it. Some programs leave it out, so a 2 in part can be read as 2 mm. Check the size after importing.

Nestor, opening soon, reads the units a DXF declares, including inches, feet, millimeters, centimeters and meters, and converts the drawing to inches; a units code it does not recognize is read as inches. A part file that declares no units is read in the unit you have chosen, and Nestor says so, with one click to read it the other way; for a sheet or remnant drawn in a DXF, switch the unit and choose the file again. It reads lines, arcs, circles, ellipses, polylines and splines, and 3D solid exports as well as flat drawings.