Convert CATPART to IGS

A customer’s CAM, inspection, or legacy CAD system may accept IGES but not native CATIA files. Converting a CATPart supplies a vendor-neutral geometry file for exchange without distributing CATIA’s editable feature history.

What the CATPART format is

.CATPart is CATIA V5’s native part-document format, used in Dassault Systèmes CATIA-based engineering workflows. It can contain parametric features, sketches, constraints, bodies, hybrid shapes, design parameters, and links to referenced data.

CATPart files are used by mechanical designers, suppliers, manufacturers, and engineering archives. A CATPart normally describes one part; .CATProduct is CATIA V5’s assembly-document format. A CATPart is not a generic mesh or interchange file, so applications without a CATIA translator usually cannot open it directly.

What the IGS format is

.igs and .iges are filename extensions for IGES, the Initial Graphics Exchange Specification. IGES stores CAD entities such as lines, arcs, curves, trimmed surfaces, and, when supported by the exporter and importer, solid boundary-representation entities.

IGES is accepted by many older CAD, CAM, CNC, inspection, and surface-modeling systems. It is a vendor-neutral, text-based exchange format, but it normally carries geometry rather than CATIA’s feature tree, sketches, constraints, design intent, or complete model metadata.

How to convert CATPART to IGS

Using CATIA V5

1. Open the CATPart in CATIA V5 and update it. Resolve missing links and confirm that the displayed shape is the intended revision.
2. Set or verify the document’s units. Hide sketches, construction geometry, datum elements, reference bodies, and other objects that must not be exported.
3. Open Tools → Options → General → Compatibility → IGES and select settings required by the receiving system. The available options depend on the CATIA configuration and installed licenses.
4. Use File → Save As, choose an IGES output type such as .igs, .iges, or CATIA’s available IGES type, and save the file with a new name such as part.igs. If no IGES type is available, the CATIA installation may lack the required interoperability capability; renaming a CATPart does not convert it.
5. Open the exported file in the recipient’s CAD system or a separate CAD viewer. Check units, bounding dimensions, holes, trimmed faces, surface gaps, and whether the model imports as a closed solid.

CATIA V5 is usually the safest option because it reads the native document and exposes CATIA’s own IGES export controls. The exported file does not retain a normally editable CATIA feature history.

Using a desktop translator

CAD Exchanger Desktop and CrossManager are commercial alternatives when CATIA is unavailable. Before purchasing or processing a batch, verify that the current product version explicitly supports CATPart input and IGES output. Import the part, choose IGES as the output format, set units, enable healing or sewing where available, and export a new .igs file.

A translator may require referenced CATIA files to be supplied with the main part, and it may not reproduce CATIA-specific features or external links. Test one representative part before converting an entire project.

Using an online service

CAD Exchanger Cloud can be considered when its current conversion interface lists both CATPart input and IGES output. Upload the file, select IGES, configure units or geometry-healing options if offered, download the result, and validate it in the target application. Online format availability can change, and a cloud service may not resolve external CATIA references.

Upload only non-confidential data to a service approved by the data owner. CATParts can contain supplier intellectual property, proprietary geometry, and linked design information; use CATIA V5 or an installed translator for restricted, regulated, or export-controlled files.

Quality and compatibility limitations

• Parametric data is lost: the recipient generally receives independent curves and surfaces, or a translated solid that cannot be edited through CATIA’s original feature tree.
• Surface healing may be required: complex parts can arrive as separate trimmed surfaces or with small gaps. Use stitch, sew, or heal tools and confirm that the result is watertight before machining or downstream analysis.
• Units can cause scale errors: IGES can store unit information, but older importers may ignore it. Compare known dimensions after import instead of relying only on the file extension.
• References and appearance may change: external links, hidden or inactive bodies, colors, layers, annotations, publications, and other metadata may be omitted or interpreted differently.
• Assemblies need separate handling: converting a single CATPart does not preserve CATProduct assembly structure or positioning. Export the required parts and assembly information using a translator that explicitly supports assemblies.
• If the receiving system supports STEP, ask whether .stp or .step is acceptable. STEP is generally a better modern exchange choice for solid and assembly data, while IGES remains common in legacy surface, CAM, and inspection workflows.