surface normal

Hi,

I have an STL model (or a VRML model) that its surface normals are not
consistent. That is, some of the normals point out and some of them
point in.

Is there a way in SolidWorks (or elsewhere) to resolve this problem and
make all the normals point out?

When I load the STL file into SolidWorks, it gives me a warning that
says: "A facet normal problem was found with one of the facets in the
file. Please check the STL file." (it's a large model and it has
several facets, so I can't possibly go through it and manually fix the
normal direction.)

When I load the VRML file (of the same model) into SolidWorks, I select
'Import as a solid body' from the load options. But the result is the
same.

Any idea?

Thanks,
Babak ( babak_taati at yahoo dot com )

 

STL and VRML are the worst formats you can try to import to SW. Can you
get a Parasolid, Step or IGES? Was the model ok before it was exported
from wherever it came from?

Does the model actually come in? If it does you can run an Import
Diagnosis on it or delete the bad faces and manually rebuild them, then
restitch the model to a solid.

 

You can use *almost any* poly mesh editor to fix these "flipped"
poly's. It's not un-common for this to happen. I think Rhino still has
a trial (time limited) version available. Most of the higher end poly
editors will fix these kinds of problems automatically. There's also a
download trial of "Modo" (www.luxology.com) that you can use to fix
this.

Mike Tripoli