Convert DXF to NC1

Steel-fabrication CNC lines often require DSTV NC files with the .nc1 extension instead of a 2D DXF drawing. The output must define machine operations and member data; renaming part.dxf to part.nc1 does not create a usable CNC file.

DXF and NC1 file roles

DXF (Drawing Exchange Format) is Autodesk’s CAD interchange format. It can store 2D and 3D entities such as lines, arcs, polylines, layers, blocks, dimensions, text, and solids; AutoCAD, BricsCAD, DraftSight, SolidWorks, Inventor, Fusion, and many CAM systems can create or import it.

Steel detailers commonly use DXF for plate outlines, hole patterns, member elevations, shop-drawing details, and reference geometry. An ordinary DXF usually does not contain the full fabrication information needed for structural CNC processing: a recognized section profile, member length, machining face, saw cuts, material data, operation types, and machine-specific rules.

.nc1 is a common filename extension for DSTV numerical-control data used in structural-steel fabrication. Depending on the software and machine, equivalent DSTV output may use .nc, .nc1, or another configured extension. DSTV data can describe a steel member’s identification, profile, length, drilling positions, hole diameters, slots, notches, contour operations, cuts, and markings.

NC1 is not a general vector-drawing format. The receiving beam line, drill line, saw, coping machine, or plate processor must support the relevant DSTV records and operations.

Choose the conversion method

For beams, columns, channels, angles, and other modeled structural parts, generate NC1 from a steel-detailing model rather than attempting a direct drawing conversion. Tekla Structures, Autodesk Advance Steel, and SDS2 can produce DSTV output from correctly modeled steelwork.

Use the structural model that already controls the project where possible. A DXF can be attached or imported as a reference for rebuilding the part, but its lines and layers do not automatically become drilling, cutting, or marking operations.

For a flat plate, nesting or machine CAM software may be appropriate if it explicitly imports DXF and exports the exact DSTV NC1 dialect required by the target equipment. SigmaNEST, ProNest, and the CNC machine manufacturer’s CAM software can import plate geometry, but many configurations generate proprietary machine code, G-code, or DXF-based output instead of NC1. Confirm the required output with the fabricator or machine vendor before selecting software.

There is no reputable general-purpose online converter that can reliably turn an arbitrary structural DXF into production-ready DSTV NC1. Such services cannot safely infer section profiles, machine faces, hole types, thickness, or cutting operations; avoid uploading controlled fabrication drawings to public conversion sites.

Prepare the DXF and create fabrication data

1. Identify the source geometry: beam elevation, member detail, plate contour, hole layout, or complete shop drawing. Obtain the target machine type, its accepted file extension, and the fabricator’s DSTV export settings.
2. Verify drawing units before import. DXF coordinates can be millimetres, inches, or effectively unitless; an inch-to-millimetre mismatch produces a 25.4-fold error.
3. Clean the source drawing in CAD. Remove title blocks, dimensions, notes, hatching, duplicate entities, and construction geometry. Convert required plate outlines to closed polylines and replace unsupported splines where the CAM importer requires arcs or line segments.
4. Rebuild or validate the physical part in the detailing or CAM system. Define the profile or plate thickness, material, length, holes, slots, cuts, notches, contours, and marks as manufacturing objects or mapped operations.
5. Set the coordinate origin, member orientation, machining faces, and operation mapping to the machine’s required convention. A DXF layer named HOLES is only a drawing convention unless the import rules map it to verified hole operations.

Export and validate NC1 output

In Tekla Structures, configure the DSTV export under File → Export → NC files. Select the applicable NC settings, output folder, part selection, hole and slot treatment, contour options, and any machine-specific settings supplied by the fabricator. Exported files are normally generated per selected fabrication part.

Advance Steel and SDS2 provide comparable NC/DSTV export functions; use their project NC settings and the postprocessor approved for the receiving shop. Do not substitute a generic postprocessor when the machine vendor has supplied a specific one.

Open every first-run file in the machine vendor’s simulator, production-control system, or a DSTV-capable checker before release. Verify the part identifier, profile, stock length, hole coordinates and diameters, face assignment, slot direction, cuts, contours, and markings against the approved drawing or model.

Compatibility limits

Not every machine supports every DSTV operation. Curved contours, complex notches, slots, countersinks, scribing, pop marks, special saw cuts, and nonstandard profiles can require a machine-specific postprocessor, a separate CAM workflow, or manual programming.

Run a test part when changing machines, postprocessors, units, profile libraries, or NC settings. A syntactically valid NC1 file can still be rejected or machined incorrectly if its member orientation, tool limits, coordinate convention, or supported operation set differs from the target equipment.