A Creo part often uses the .prt extension, and a Creo assembly often uses .asm. Those names are not enough to choose a reader. Siemens NX also uses .prt. CADProps recognizes Creo / Pro/ENGINEER PRT and ASM separately from NX and can show their supported saved thumbnail. This is a file check and thumbnail preview, not Creo 3D viewing. No native Creo measurement or STEP export is available.
Use the Creo file check on the original .prt, .asm, .prt.N or .asm.N file. Keep numbered save suffixes. For 3D geometry, ask the Creo owner for a STEP export.
Identify the source before you pick a tool
| Evidence | Reasonable conclusion |
|---|---|
| The sender says Creo or Pro/ENGINEER | Do not use the NX PRT viewer as if it were Creo |
| The sender says NX or UG and the release | The NX PRT path may apply |
Only the .prt extension is known |
The source is still unidentified. See NX or Creo PRT |
| A STEP file was exported from Creo | Open that STEP. The extension of the native master no longer matters |
Changing .prt to .step, .stp or a version suffix does not translate Creo data. A file icon does not identify the kernel.
What to request from the Creo user
Ask for a STEP export of the released configuration, in the units the drawing uses, with the bodies or assembly components you need to see. If the model is a family table or a simplified representation, name that state. A default export can omit the instance you were quoting.
Creo assemblies depend on part files. A single top-level file is not a complete product. The STEP should be self-contained, or the sender should package the references in the way their export actually embeds them. CADProps can show a saved ASM thumbnail, but does not decode its assembly structure or verify component placements. A ZIP can select the highest numeric save for an unversioned model path, but still cannot reconstruct Creo geometry.
STEP from Creo is still an exchange derivative. It does not recreate Creo features, relations or the model tree as an editable Creo file. Keep the native files when someone must change the design later.
Check the STEP you receive
Open it in the STEP viewer.
- Confirm the part or assembly name against the revision you expected.
- Read missing-component warnings before measuring an assembly.
- Compare one known dimension with the drawing. Fit-to-view is not a unit check.
- Use volume only when the geometry is a valid closed solid. An open quilt can look solid and still have no volume.
- Treat mass as volume times a density you choose. A Creo material parameter does not automatically travel as a certified mass.
A scale that is off by 25.4 usually means an inch/millimetre interpretation problem. Resolve that before converting again or quoting weight.
If you only have the Creo file
Check the saved thumbnail if it is available, then ask for STEP when you need geometry. A missing thumbnail does not make a recognized Creo file corrupt; the image may be absent or unsupported. Do not present that image as a decoded model. STL has no reliable unit declaration, and a mesh does not restore the precise surfaces.
The saved thumbnail has no measurable model scale, area, volume or calculated mass. It does not establish the current revision or complete assembly scope. Export STEP from Creo for those geometry tasks.
Request the correct family-table instance and assembly state
Ask the Creo owner to name the instance or simplified representation represented by the export. A generic family-table part and the released instance can share an overall resemblance while having different holes, lengths or included features. The STEP should correspond to the state named in the purchase or review record.
For an assembly, request the intended component scope and placements, not merely an export that opens without errors. If several purchased components are intentionally excluded, keep that exclusion list with the derivative. An omitted component and a failed component must not receive the same “complete” label.
After import, compare one overall dimension and one feature that distinguishes the intended instance. If both match, continue with the task-specific checks; they do not prove every engineering requirement transferred. Tolerances, threads and material still need the controlling specification.
If the sender cannot export, use a compatible Creo authoring or qualified native-reader workflow outside CADProps. The NX path is not a fallback decoder for an unidentified Creo file, and a renamed extension cannot make it one.
Original article: CADProps · https://www.cadprops.com/guides/open-creo-without-creo/