Key Takeaways

• Export DXF in AutoCAD 2013 (R21) format or earlier — not DXF 2018 or newer.
• All cut lines must be at scale 1:1 in millimetres with all paths closed.
• Remove all dimensions, hatching, annotations, and title blocks from the file.
• Run OVERKILL (AutoCAD) or equivalent to eliminate duplicate overlapping lines.
• Minimum hole diameter = material thickness for steel ≤ 4mm; 1.5× thickness for thicker material.

How to Prepare a DXF File for Laser Cutting

A correctly prepared DXF file is the single biggest factor in whether your laser cut parts come out right. Formatting errors — open paths, wrong units, duplicate lines — cause rejection, rework, or mis-cut parts. This guide covers everything you need to produce a clean DXF from Fusion 360, AutoCAD, SolidWorks, or Inkscape.

What is a DXF File?

DXF (Drawing Exchange Format) is a CAD data file format developed by Autodesk. It describes 2D vector geometry — lines, arcs, and polylines — that laser cutting software uses to generate the cutting path. Unlike PDF or raster formats, DXF preserves exact geometry at any scale and is universally supported by laser cutting machinery worldwide.

Ferracut also accepts DWG files. DXF is preferred because it works across every CAD and vector tool without requiring a specific AutoCAD version.

Universal DXF Requirements for Laser Cutting

• Units: Millimetres. If your CAD tool defaults to inches, convert before export.
• Scale: 1:1. File dimensions must match the physical dimensions of the part.
• Format: AutoCAD R14 to AutoCAD 2013 (R21). Avoid DXF 2018+ for best compatibility.
• Geometry: All cut profiles as closed, continuous polylines or paths — no open ends.
• Layers: Cut geometry on one layer only. Remove dimensions, hatching, title blocks, and annotations.
• Duplicates: No overlapping lines — these cause double-cutting and quality issues.

Exporting DXF from Fusion 360

Fusion 360 requires exporting from a sketch, not a 3D body:

1. In the Design workspace, open the sketch containing your flat profile.
2. Right-click the sketch in the browser tree.
3. Select Save As DXF.
4. Confirm units are millimetres in File → Document Settings → Units.

If you only have a 3D body, right-click the face you want to cut → Create Sketch to project the profile. For sheet metal parts, unsuppress the Flat Pattern feature first.

Watch for: Splines that cannot be reproduced by the laser. Replace splines with tangent arcs in the sketch before export.

Exporting DXF from AutoCAD

1. Draw your part in Model Space at 1:1 scale in millimetres.
2. Move all cut geometry to a single layer (e.g. LASER_CUT) and freeze all other layers.
3. Use SAVEAS → AutoCAD R12/LT2 DXF or any version up to 2013.
4. Run OVERKILL to remove duplicate entities before saving.
5. Run PEDIT → Join to convert disconnected line segments into continuous polylines.

Exporting DXF from SolidWorks

1. Open the part and right-click the face to be cut.
2. Select Export to DXF/DWG → choose Export face/loop.
3. Choose DXF format, AutoCAD 2013 or earlier, units in millimetres.

For sheet metal flat patterns: right-click the Flat Pattern feature in the feature tree → Unsuppress, then File → Save As → DXF.

Exporting DXF from Inkscape

1. Set document dimensions to your part size in millimetres (File → Document Properties).
2. Convert all text to paths (Path → Object to Path).
3. Ensure all cut shapes are closed paths (use Node Editor — N key — to verify).
4. File → Save As → Desktop Cutting Plotter (AutoCAD DXF R14).
5. Set base unit to mm in the export dialog.

Common Inkscape issue: Paths that appear closed on screen but have a tiny gap at the node. Zoom in at every node junction and snap endpoints together.

Kerf Compensation

The laser removes material equal to the kerf width — typically 0.1mm to 0.3mm depending on material and thickness. For most parts, Ferracut applies standard kerf compensation automatically. For precision press-fit assemblies (tabs and slots designed to interlock):

• Offset tab widths outward by 0.1mm
• Offset slot widths inward by 0.1mm

This compensates for the typical kerf on mild steel up to 6mm. Always prototype and adjust for critical fit applications.

Minimum Feature Sizes

• Minimum hole diameter: Equal to material thickness for steel ≤ 4mm; 1.5× thickness for thicker material
• Minimum bridge width: 1mm for thin material, increasing with thickness
• Minimum detail size: 0.8mm for fine patterns in mild steel ≤ 1.5mm

Pre-Upload Checklist

• All paths are closed
• Units are millimetres, scale 1:1
• No overlapping duplicate lines
• Dimensions and annotations removed
• Cut geometry only — no construction lines
• File saved as AutoCAD 2013 or earlier DXF
• All text converted to paths

Get Your Parts Cut Today

Ready to put this into practice? Upload your DXF or DWG file to Ferracut and get an instant quote in under 30 seconds — no emails, no waiting, no minimum order.