Convert SLDPRT to IGS

A supplier, inspection system, legacy CAD application, or CNC workflow may require IGES instead of a native SolidWorks part file. Exporting to IGES exchanges the part’s geometry, but it does not preserve SolidWorks’ editable feature history.

What the SLDPRT format is

.sldprt is SolidWorks’ native part format, created by Dassault Systèmes. It stores a part’s parametric feature tree, sketches, dimensions, configurations, materials, and one or more solid or surface bodies.

SolidWorks designers, mechanical engineers, manufacturers, and suppliers use SLDPRT files. An SLDPRT is a part document, not an assembly container; assemblies normally use .sldasm and reference separate part files. Export each required part individually, or use an assembly-capable translator when the source is an assembly.

What the IGS format is

.igs and .iges are filename extensions for IGES, the Initial Graphics Exchange Specification. IGES can describe wireframe entities, trimmed surfaces, and boundary-representation solid geometry for CAD, CAM, inspection, and visualization software.

Its main benefit is compatibility with older and cross-platform systems that cannot open SolidWorks files. The exported file normally contains geometry only; sketches, feature trees, equations, mates, configurations, native materials, and parametric editability are not retained.

Convert with SolidWorks

1. Open the SLDPRT in SolidWorks. Resolve rebuild errors; Ctrl+Q forces a full rebuild, but review the resulting warnings before exporting.
2. Select the required configuration and suppress unwanted bodies or features. Check the final dimensions, body count, and document units.
3. Choose File → Save As, set Save as type to IGES (*.igs) or IGES (*.iges), choose a destination, and select Save.
4. In the IGES export options, choose the representation supported by the recipient. Prefer a solid or trimmed-surface export when the receiving system supports it; surface-only output may be required by older importers.
5. Set the export units to match the receiving system and enable available healing, sewing, or solid-formation options when appropriate. Option names and availability vary by SolidWorks release and model type.
6. Open the resulting IGS in the target application or an independent CAD viewer. Check scale, bounding-box dimensions, holes, critical mating faces, gaps, missing faces, and the number of imported bodies.

SolidWorks is usually the safest option because it reads the native feature tree and evaluates the original model before translation. Autodesk Inventor can also open many SLDPRT files and export IGES, but support and menu names depend on the Inventor release and installed translators.

Alternative desktop and online converters

CAD Exchanger Desktop is a practical alternative when SolidWorks is unavailable. Confirm in the current edition that SLDPRT import and IGES export are included; format support can vary by product edition and release.

CAD Exchanger Cloud can provide the same workflow in a browser when its current format list supports both .sldprt input and IGES output: upload the part, select IGES, download the result, and validate it in a separate viewer. Online CAD converters are unsuitable for confidential, customer-owned, or export-controlled models unless their retention, deletion, encryption, and data-processing terms have been approved. Do not assume that general file-conversion sites support SLDPRT reliably; many cannot parse SolidWorks’ native format.

Quality and compatibility limits

IGES translation can produce disconnected faces instead of a watertight solid, particularly around small fillets, complex blends, imported geometry, and models with tolerance or rebuild errors. If the recipient reports open edges or an invalid body, retry with another IGES representation and available sewing or healing settings, then inspect the result manually.

Verify units after import because some older applications misread IGES unit metadata. Compare bounding-box measurements, hole diameters, and functional surfaces with the original SLDPRT. Colors, textures, sheet-metal intelligence, product-manufacturing information, annotations, configurations, and other non-geometric data may be lost or only partly translated.

When the receiving system accepts it, STEP is often preferable for modern CAD exchange because it generally preserves solid topology more reliably than IGES. Supply the original SLDPRT as well when the recipient needs editable SolidWorks history.