Hi Martin, that STEP file contains triangle mesh data, not CAD surfaces and solids which is what MoI is generally expecting to be in a STEP file.

I'll take a look at why it would load in MoI v3 and not in v4 but I do not generally expect for this type of faceted triangle mesh data to load well into MoI in the first place. I don't recommend trying to work with polygon data in MoI, it's not designed for that.

- Michael

Hi Michael,

Thanks for the advice. I use this workaround in Moi based on such STEP files to transfer polygon/stl mesh to cleaned up solid models for hard surface modeling.
As mentioned, in V3 there are no issues with that.

Good luck with the analysis.
Regards,
Martin

Hi Martin, so yes this has to do with the particular kind of mesh entity in your STEP file, the STEP "FACETED_BREP" entity type. This is a separate issue from what Rico wrote about above.

Moi v3 did load the "FACETED_BREP" entities but that got broken in v4 since the Jun-6-2018 v4 beta release which reworked the STEP importer to use multiple CPU threads.

This is the first time it's been reported in the last 3 years because it's kind of an obscure and rarely used area. I'll see about restoring the v3 behavior for the first v5 beta release.

Thanks for reporting it and sending the file!

- Michael