Convert SLDPRT to CAD

A supplier or manufacturing system may not open a native SolidWorks part, so the model must be delivered in a neutral format such as STEP or IGES. The required output depends on whether the recipient needs editable 3D geometry, a 2D profile, a mesh for printing, or only a visual reference.

What the SLDPRT format is

.sldprt is SolidWorks’ native part-document format. It can contain a feature tree, sketches, dimensions, equations, configurations, materials, appearance data, and one or more solid or surface bodies. An .sldprt file represents a part document; SolidWorks assemblies and drawings normally use .sldasm and .slddrw.

SolidWorks and compatible SolidWorks-based applications can preserve and edit the feature history when the file is opened in a supported version. Most other CAD systems cannot. Exporting usually replaces the parametric design with an imported boundary-representation solid or a collection of surfaces, so features, equations, configurations, and design intent are not retained.

What “CAD” means here

CAD is a category of software and data, not one universal file format or extension. Confirm the recipient’s required format before exporting:

• STEP (.step or .stp) is the usual neutral choice for accurate 3D exchange. AP214 or AP242 may preserve colors and additional product information, but support varies by application; use the protocol requested by the recipient.
• IGES (.igs or .iges) remains useful with legacy systems and surface-based workflows. It is more likely than STEP to produce disconnected surfaces or require repair.
• Parasolid (.x_t or .x_b) often transfers high-quality solid geometry between systems using the Parasolid kernel, but licensing and importer support are less universal than for STEP.
• DXF or DWG is intended for 2D drawings, profiles, laser cutting, routing, and CNC documentation. It is not a replacement for a complete 3D part.
• STL (.stl) stores a tessellated triangle mesh for 3D printing, visualization, or inspection. It has no exact analytical faces, feature history, dimensions, or reliable manufacturing intent.

If the request only says “CAD file” and concerns a 3D mechanical part, ask whether STEP is acceptable. Do not assume that a file with a generic CAD-related extension will meet the recipient’s import requirements.

How to convert the part in SolidWorks

1. Open the .sldprt file in SolidWorks. If the file came from a newer release, an older SolidWorks version may not open it; use the originating release, a compatible translator, or request a neutral export.
2. Force a rebuild with Ctrl+Q and resolve rebuild errors. Select the required configuration, check suppressed features and hidden bodies, and remove or suppress geometry that should not be delivered.
3. Check document units through Tools → Options → Document Properties → Units. Units are generally written into STEP, but confirming them prevents interpretation errors in downstream software.
4. Choose File → Save As, select the requested format, and open Options if available. For a general 3D exchange, choose the recipient’s supported STEP protocol, such as STEP AP214 or STEP AP242. Set the output coordinate system and other available geometry options.
5. Save under a new name, for example bracket_revA.step. Keep the original .sldprt unchanged.
6. For a 2D result, open the drawing and save it as DXF or DWG, or select the required planar model face when exporting directly from a part. Confirm the sheet or face, scale, units, line types, and exported views or sketch entities.
7. Reopen the exported file in the recipient’s CAD system or an independent CAD viewer. Check the origin, orientation, body count, critical dimensions, holes, threads, fillets, small faces, and the presence of gaps or invalid solids.

SolidWorks is normally the preferred exporter because it can read the native document and expose its export settings. A STEP, IGES, Parasolid, or STL file will not normally recreate a SolidWorks feature tree in the destination system.

Desktop and online alternatives

CAD Exchanger Desktop can read and write several engineering formats, including SolidWorks parts and common neutral outputs, when the installed version supports the specific SLDPRT version. Import the part, inspect the body structure, choose STEP, IGES, or another required output, set units or tessellation options where applicable, and export. Verify the result rather than relying on a completed status message.

CAD Exchanger Cloud and Onshape can provide browser-based translation when their current import and export lists include the SLDPRT version and target format. Upload or import the part, export it as STEP or the requested format, and download the result. Cloud interfaces and supported formats change, so check the provider’s current documentation before starting.

Do not upload confidential designs, export-controlled data, customer models, or proprietary geometry without authorization. Online services may reject encrypted files, unsupported SolidWorks versions, unusually complex features, or multi-body parts, and uploads can be subject to file-size and storage limits.

Quality and compatibility limitations

Neutral export generally discards SolidWorks feature history, equations, mates, configurations, drawing links, design tables, and manufacturing annotations. STEP preserves precise boundary-representation geometry, but the receiving system may show the result as a single imported feature such as Imported1 rather than as editable sketches and features.

Multi-body parts can import as separate solids, a compound, or one merged body depending on the exporter and recipient. If individual bodies are required, confirm the recipient’s import behavior or export the bodies separately. Assemblies require additional handling: an .sldprt contains only the part document, while an assembly’s component structure and references belong to the .sldasm and its associated files.

STL is unitless in many workflows. Set deviation and angle tolerances finely enough for the required surface accuracy, then inspect curved faces and small features; a coarse mesh cannot be converted back into exact parametric geometry. DXF and DWG workflows can also lose 3D information and may be interpreted at the wrong scale if units are not explicitly set.

Before release for manufacturing, compare key measurements with the source model and inspect the exported file for missing faces, gaps, bad edges, incorrect orientation, changed body count, and unintended features.