Convert SLDDRW to STP

A receiving CAD or CAM system may require a STEP model for measurement, editing, machining, or inspection, while the available SolidWorks file is only a drawing. Converting it requires the drawing’s referenced part or assembly files; an .slddrw cannot normally supply the complete 3D geometry by itself.

What the SLDDRW format is

.slddrw is the native 2D drawing format used by Dassault Systèmes SolidWorks. It stores drawing sheets, projected and section views, dimensions, annotations, tables, drawing resources, and links to source .sldprt part or .sldasm assembly files.

Manufacturers and engineers use SLDDRW files for production drawings, inspection documentation, fabrication instructions, and design records. The file normally references the 3D model rather than containing a complete, independently exportable solid. Its views and dimensions describe the model but do not replace the model’s topology, features, or assembly relationships.

What the STP format is

.stp and .step are filename extensions for ISO 10303 STEP files. STEP exchanges 3D CAD data between applications such as SolidWorks, Siemens NX, CATIA, Autodesk Inventor, Fusion, FreeCAD, and many CAM systems.

A STEP file can contain solid bodies, surface geometry, assemblies, colors, and limited product-structure or metadata information, depending on the selected application protocol and exporter. It is suitable when the recipient needs to measure, modify, assemble, machine, or inspect the actual 3D design rather than view drawing annotations.

How to convert the drawing’s referenced model

Using SolidWorks

1. Open the .slddrw in SolidWorks and identify the model behind a drawing view. Right-click a view and choose Open Part or Open Assembly, or inspect the view’s model reference.
2. Open the corresponding .sldprt or .sldasm. Resolve missing components and rebuild the model. For an assembly, use File → Pack and Go when you need to collect referenced component files before transferring the job.
3. Choose File → Save As, select STEP AP214 (*.step; *.stp) or STEP AP242 (*.step; *.stp) if available, and open the export options.
4. Set the required assembly and geometry options. Preserve assembly structure when the recipient needs separate components and placements; export a single combined file only when the receiving system requires one file or the structure is irrelevant.
5. Save the file and reopen it in the target CAD system or an independent STEP viewer. Check units, body count, holes, curved faces, colors where relevant, and assembly placement.

SolidWorks is usually the safest desktop choice because it can resolve native drawing references and export the original model without reconstructing geometry. Export the drawing separately with File → Save As to PDF or DXF if the recipient also needs dimensions, notes, or title-block information. eDrawings and ordinary drawing viewers can display SLDDRW content but are not substitutes for a model exporter.

Using another desktop CAD application

Another CAD system can export the source .sldprt or .sldasm if it supports that SolidWorks version and file type, but native SolidWorks support varies. Confirm that the imported model is valid before choosing Export or Save As for STEP. A neutral format such as STEP may lose parametric history even when the geometry imports correctly.

Using an online converter

An online service cannot reliably convert an SLDDRW-only file into a true STEP model because the required 3D source is absent. After obtaining the referenced .sldprt or .sldasm, a service such as CAD Exchanger Cloud/Web may convert supported SolidWorks model files to STEP; verify current format, version, assembly, and file-size support before uploading.

Cloud conversion is unsuitable for confidential designs unless the organization has approved the provider’s storage and data-handling terms. It can also fail when external references, configurations, suppressed components, or proprietary SolidWorks features are unresolved. Do not upload the drawing expecting the service to infer hidden geometry from its views.

When only the SLDDRW file exists

There is no dependable one-click conversion from a drawing to a complete STP model. Projected views and dimensions do not uniquely define hidden faces, fillets, threads, wall thicknesses, design intent, or assembly mates; shaded views and silhouette edges are visual references, not source solids.

Recreate the part or assembly in SolidWorks, another parametric CAD system, or a direct modeler using the drawing’s dimensions and notes, then export the reconstructed model as STEP. Mark the result as reconstructed because it may differ from the original design in topology, tolerances, feature behavior, and assembly relationships.

Quality and compatibility limits

• Request the original .sldprt, .sldasm, and all referenced components instead of relying on the drawing alone.
• STEP does not preserve SolidWorks feature history, sketches, mates, configurations, or drawing annotations. It transfers exchange geometry and, depending on the exporter and importer, limited assembly structure and metadata.
• AP214 and AP242 generally provide more product-structure and color support than older AP203 exports, but the receiving application determines which protocol is safest.
• STEP stores units, but import settings can still produce an apparent scale error. Measure a known dimension after import.
• Check invalid or missing faces, tiny gaps, trimmed surfaces, suppressed components, and assembly positions before using the file for machining or production.