Imported OBJ From Inventor Loses Smooth Curves

[kschmidtBPQPG]

 When importing .obj from inventor all the curves, radii, and circles completely get destroyed. If I use smoothing or subdivisions, it works. However, I need to retain the sharp edge along the chamfers. All of the smoothing features in 3ds Max end up rounding my chamfers. 

 How it looks in a render.

[Diffus3d]

I think what you are describing are not curves, but normals.  3dsmax uses something called smoothing groups to quickly smooth normals between faces.  When you export/import your model, make sure that normals are checked because that is what is going bad on you.

It's pretty easy to reset smoothing groups if your model imports without them though.  Here is some information about them.

Best Regards,

[kschmidtBPQPG · Accepted solution]

Im sure yours is the proper solution, but I imported through .step files instead and it kept the correct "smoothing". Thanks though!

[Diffus3d]

Good to hear!  Thanks for the update.

Best Regards,