Actually, not all translators are created equal. Since each translator
is written independently by each CAD company, to the STL file format
specification developed by 3D, they can vary greatly in how they choose
to output it. These differences can range from too many triangles to
mismatched or missing triangles. How the accuracy of the file is
controlled can vary greatly also. One translator may use a chordal
tolerance value and an angle control value (Pro E), another may use a
non descript accuracy value that doesn't really relate to any real
feature on the part, while another may not give you any control at all.
For example, a good translator would define a cube with 12 triangles.
Another may completely cover the part with tiny triangles and create a
large file. Hope this helps, Todd Stahlhut
----------
From: adatt@iitk.ernet.in
To: corcor@ibm.net
Cc: rp-ml@bart.lpt.fi
Subject: Re: CATIA-to-STL (was: IGES to STL)
Date: Wednesday, March 18, 1998 4:40AM
I am unable to understand the line: "file was always small". As per my
understanding, the file size depends on the triangulation parameters, so
it is independent of the translator used. Pl. correct me if I am wrong.
Regards.
A. D. Bhatt
>
> This is a multi-part message in MIME format.
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>
> Hello people,
>
> I have extensive experience with STL generation from CATIA. When ever I
> received an STL file from CATIA the file was always small and easy to
> process. Most of the files we generate from CATIA can be emailed. I think
> you will find that the resolution chosen for your parts is way to high to be
> producing such large files. Try a SAG value of 0.03 and "MAX size of
> Triangles" of 200 (this will depend on the part). Solids and volumes
convert
> extremely well. To convert a surface model it would be better to join
all the
> faces together into a skin first. This eliminates the problems of reversed
> normals and gaps.
>
> I hope this can help?
>
> Daniel Corcoran
>
> DAN DAVIS, RAPID PROTOTYPE wrote:
>
> > Brandon, Victor and all:
> >
> > I do have the v4.1.7 CATIA translator, but find that it creates really,
> > really large STL files (i.e., a quarter scale, 10-spoke cast aluminum
> > car wheel was over 7Mb). Do you find this also?
> >
> > I've heard that this was a problem at Chrysler in the past and they
> > switched to the Brockware translator. I was wondering if this is still
> > the case or is it that my engineers do not know what settings to use for
> > the translation?
> >
> > Please keep in mind that I am not really a CAD expert -- I know just
> > enough to get into trouble.......
> >
> > Regards,
> > > Dan Davis
> > > Division Head, RP&M
> > > Perusahaan Otomobil Nasional Berhad (PROTON)
> > Hicom Industrial Estate
> > Batu 3 PO Box 7100
> > Shah Alam, Selangor D. E.
> > 40918 MALAYSIA
> > > +60 3 515-3906 direct line
> > > +60 3 515-2380 direct fax
> > > +60 12 277-5770 hand phone
> > >
> > >
> > >
> > >
> > > ----------
> > > From: Brandon Jacobsen[SMTP:brandonj@eagledesign.com]
> > > Sent: Monday, 16 March, 1998 19:32
> > > To: DAN DAVIS, RAPID PROTOTYPE
> > > Subject: Re: IGES to STL
> > >
> > > Dan,
> > >
> > > I am not familiar with brockware's CATIA to STL translator, but we
> > > have done extensive work with the CATIA STL package
> > > available in v4r1.7 and up. It is a little costly but it is an
> > > excellent stl translator. The major advantage of the CATIA
> > > translator is that you are 99.99% guaranteed a good STL file if you
> > > have a Volume or solid. And an offset function that takes
> > > a single stl of a skin and gives it thickness, which is great for
> > > rapid tooling. If you have any questions please feel free
> > > to call.
> > >
> > > Brandon R. Jacobsen
> > > Eagle Design & Technology, Inc.
> > > phone: (616) 748-1022
> > > fax: (616) 748-1032
> > >
> > > "If one synchronized swimmer drowns, do the rest have to drown too?"
> > >
> > >
> >
> > ------------------------------------------------------------------------
> >
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> > Encoding: base64
>
>
>
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> fn: Daniel Corcoran
> n: Corcoran;Daniel
> org: Concentric Asia Pacific
> email;internet: corcor@ibm.net
> title: Industry Specialist
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>
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