STP/STEP import now has problems in 2024

[Ross2006]

Our team has just upgraded from 3ds Max 2018 to 3ds Max 2024, and we've noticed some new problems when importing STEP files. The ATF Converter (STEP translator) occasionally had some trouble with certain torus shapes back in 3ds Max 2018, but now it's much worse and has started to affect our productivity since we need to manually fix these glitches with each new import.

I created some torus and partial-torus shapes in my CAD program and exported the file as STP. You can download the file in the attachments and test it yourself.

Here's how the import looks in 2018 - absolutely perfect:

Here's in 2024 - quite broken:

As you can imagine, toruses appear frequently in our CAD models so this is a bit of a dealbreaker.  Hopefully this helps get to the root of the problem and we won't have to stick with 2018

[RobH2]

I was unable to reproduce the issue. I uploaded a video showing opening in  my CAD software to see if it looked normal there first. Then I opened in Max and it looked good as well. STL Check found no errors. 

Have you tried exporting from CAD as  something other than STP and imported that? I mean, if you just need to get it into Max, it doesn't stay a STP once in Max, it's just a mesh and you can export another or the same format once you are done with it. 

Have you tried and ENU reset?

[wernienst]

Unfortunately, you are right - partly.

Left: Convert to Mesh Off, right: Convert to Mesh: On

[wernienst]

The problem is not the STEP importer. It's the mesh creation process inside Max' Body Objects.

Left: Display Options Both, right: Curves