Hi Anis,

I had a look at this model and unfortunately it's a mess, it seems that the person who modeled this part has had the modeling tolerance set very loose in their cad program.
Ralf was correct, it was exported from NX, I've highlighted it in the picture attached.

I did run some analysis in NX, also NX has a feature called heal geometry, what that does is it tries to fix geometry by tightening tolerances, removing tiny objects and various other surface repairs, it works quite well when there a few geometry abnormalities, I've also attached the output result of that operation and you can see how many things are wrong with this model, but there were still a lot of naked edges after this operation, the best you could get was to sew(join) the surfaces in NX using a tolerance of 0.1mm(0.004") which in my opinion is way too loose, I wouldn't trust the quality of any of the surfaces and it still resulted in a lot of naked edges that would take some hours to fix.

Anyhow there is no quick fix for this file, I suggest if your client is using NX 5.0 I can't see why they can't output it as a STEP to see if that is any better.






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