Strange triangels / quads appearing - vray rendering

Dear all,
I posted on this forum once before and got a brilliant response, now I’m asking for help once more. It might be a stupid question, therefore I hope someone has a simple answer.

I received an IGES files from the company, I imported it, cleared all the duplicates, joined all the surfaces and when I finished applying materials I found that (please see file attached) where my glass material is in direct contact with any other material, there are some triangles (pic2 -from iges) or quads (pic 1 - rebuilded geometry) rendered.

file_1.3dm (2.4 MB)

I tried rebulding the geometry for test, but got the same results - I think that the problem is not in geometry itself, but rather that I am doing something wrong…

Since I’m really on the tight schedule (well the client is really :slight_smile: ) I kindly ask you for any answers or tips that would solve this, I’m getting pretty desperate.


Try leaving a very small gap between the two materials. I’m assuming the inside of the glass and outer edge of the plastic surfaces are coincident - two materials occupying the exact same space often causes issues in rendering.

Thanks for your reply!
Yes, they are, but when I resize the glass tube, everything behind the glass material gets really blurry - that’s probably a material issue, I tried a whole library of glass material but still no luck …

Just shrink the inner plastic ring slightly, so it isn’t exactly on the glass, and it works.

Also, the tolerances in your file are very loose, although it isn’t seeming to affect Vray. You are using meters and an absolute tolerance of .01, while your wall thickness is less than that. Try changing your tolerance to .00001 or your units to mm and tolerance to .01 or .001.