Holes stay holes
Loops inside a shape are cut out, and loops inside those holes turn solid again.
Convert DXF to STL by Extruding 2D Outlines
Drop a laser, CNC or CAD drawing. Closed shapes turn solid, inner loops stay holes, and you set the thickness in mm. Nothing uploaded.
Drawing units
Loading 3D preview
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3.0 mm
100 %
0.05 mm
Built in your browser. Files are never uploaded.
Before and after the extrusion
Inspect the drawing, check the finished STL, or make the lettering a DXF cannot carry.
From DXF to STL in three steps
- 1
Open the DXF
Drop the file or click to choose it. Units come from the file header, and a sample plate is loaded so you can try it first.
- 2
Pick layers and thickness
Tick the layers to extrude, set the thickness and scale, and add a backing plate if you want raised shapes on a base.
- 3
Download and slice
Check the size and the watertight result, then download STL or 3MF and open it in your slicer.
From 2D outline to 3D plate
The sample mounting plate as drawn, and after this tool extrudes it.
Why use this DXF to STL converter
Made for laser, CNC and CAD outlines that need to become printable parts.
Pick the layers
Each layer lists its closed and open shapes. Layers with only text or open lines start unticked.
Gap closing
Loose ends closer than the value you set, up to 2 mm, are joined into closed outlines.
Units from the file
Drawing units come from the DXF header and are converted to millimeters. Pick one when the file has none.
Backing plate
Raise the shapes on a rounded plate that follows the drawing, with your own margin and thickness.
Checked before download
Every edge of the result is counted, and a warning shows when the part is larger than a 256 mm bed.
Settings for flat parts
Four choices that keep a plate flat, stiff and the right size.
Face down, no supports
An extruded part has a flat bottom, so it prints straight on the bed without supports.
Three or four walls
For stiff plates use three or four walls and 20 to 40 percent infill.
Oversize small holes
Small holes print a little tight. Draw bolt holes 0.2 to 0.4 mm larger, or drill them out.
3MF keeps the units
A 3MF stores millimeters as its unit, so the slicer never has to guess between inches and millimeters.
Parts people make from a DXF
Drawings made for a laser or CNC print well. Thickness ranges are for PLA or PETG on a 0.4 mm nozzle.
Spacer or shim
Thickness is the dimension that matters, so measure a test print
0.5 to 3 mmGasket
Print in TPU, slowly, with 100 percent infill
1 to 3 mmSign or name plate
Turn on Backing plate for raised letters
3 to 5 mmDrill template or jig
A thicker plate guides a drill straighter
4 to 10 mmDXF to STL guide
Closed contours, CAD fixes, thickness and slicing in detail.
Closed vs open contours
A 3D print needs a solid with a closed skin, so only shapes whose outline closes on itself can be extruded. Circles, closed polylines and closed splines are closed by definition. Loose lines and arcs are chained end to end, and a chain that returns to its start, within the gap setting, counts as closed.
Inside a closed shape the next loop in is a hole, the loop inside that hole is solid again, and so on. That is how a washer keeps its centre hole and a letter O keeps its counter. Open contours, such as a centre line or an outline with a gap, are skipped and drawn in red on the 2D outline so you can see exactly what is missing.
How to fix open contours in your CAD program
For tiny gaps, raise Close gaps here. It joins loose ends that are closer than the value you set, up to 2 mm, without changing the rest of the drawing.
For bigger gaps, fix the source. In AutoCAD, JOIN merges touching lines and arcs into one polyline, and BOUNDARY draws a closed polyline around any enclosed area. In LibreCAD or QCAD, snap to the endpoints and redraw the missing piece. In Inkscape, join the end nodes of the path before you export. Delete lines drawn twice on top of each other, and keep dimensions and notes on their own layer so you can leave it out.
How thick should it be?
These are starting points for PLA or PETG on a 0.4 mm nozzle. Print a small test first when a part has to fit something.
Spacer or shim
- Thickness
- 0.5 to 3 mm
- Tip
- Thickness is the dimension that matters, so measure a test print
Gasket
- Thickness
- 1 to 3 mm
- Tip
- Print in TPU, slowly, with 100 percent infill
Stencil
- Thickness
- 0.8 to 1.6 mm
- Tip
- Thin enough to lie flat, stiff enough to hold its shape
Sign or name plate
- Thickness
- 3 to 5 mm
- Tip
- Turn on Backing plate for raised letters
Mounting plate
- Thickness
- 3 to 6 mm
- Tip
- Make bolt holes 0.2 to 0.4 mm oversize
Drill template or jig
- Thickness
- 4 to 10 mm
- Tip
- A thicker plate guides a drill straighter
What to make from a DXF
Files drawn for a laser or CNC are the easiest win. A plate meant to be cut from 3 mm acrylic can be printed 3 mm thick instead. Typical jobs are mounting plates and brackets, spacers and shims, TPU gaskets, signs and name plates, stencils, drill templates and replacement covers.
TEXT and MTEXT entities are not extruded. Explode text to outlines in your CAD or design program first, or make lettering with the Text to STL tool. Hatches are skipped too, because the boundary lines around them usually carry the shape.
Slicer tips
The STL is in millimetres, centred and flat on the bed, so it opens at the right size in Cura, PrusaSlicer, OrcaSlicer or Bambu Studio. 3MF records the unit inside the file, which removes any doubt about inches and millimetres.
Print flat parts face down with no supports. For stiff plates use three or four walls and 20 to 40 percent infill. Small holes often print a little tight, so drill them out or add clearance in the drawing.
DXF to STL questions
Answers about open contours, holes, units, layers and watertight files.
Why does it say my DXF has open contours?
Some lines or arcs do not meet end to end, so they do not enclose an area. Switch to the 2D outline to see them in red. Raise Close gaps for tiny gaps, or join them in your CAD program.
Will holes stay as holes?
Yes. Loops inside a closed shape are cut out, and loops inside those holes become solid again, so washers, frames and stencils keep their openings.
What units does the STL use?
Millimetres. The tool reads the units from the DXF header and converts them. If the file has no unit, millimetres are assumed and you can pick inches or another unit.
Can I extrude only some layers?
Yes. Tick the layers you want. Layers with only open lines or text, such as centre lines and notes, start unticked.
Can I make a sign with raised letters on a plate?
Yes, if the letters are outlines in the DXF. Turn on Backing plate and the shapes sit on a rounded plate that follows the drawing, with the margin and plate thickness you choose.
Is the STL watertight?
The tool counts every edge of the finished mesh and shows the result next to the download button. A clean closed outline gives a closed solid that slicers accept without repair.