Dear Prototypers and Toolers,
Thanks for all the reactions I recieved on the subject below. It has been
very useful, here a summary of the reactions we recieved:
The following question was posted on the RPML two weeks ago:
Dear toolers and mailers,
We've discussed this topic many times, but the process is still not at its
best so I would like some further feedback on this:
I know about most IGES to STL converters and IGES-fixers, stand alone as
well as modules of big CAD-packages. And they all promise wonders of course!
That's why I would very much like to know the experience of other users:
What package do you use to generate STL files from a surface or solid model
and are you satisfied? If you have a little more time: What is the quality
of the generated stl-files (overlapping, thin, reversed triangles etc?)
Same question for IGES fixers?
Best regards and have a nice weekend,
Bart Kooijmans
The next page is a summary of the reactions we received, followed by the
complete mails.
* 3D modelserver
Internetsite which claims to repair CAD-files for a certain amount of money
per X MB. Also for sale for internal use. No further information on which
formats it can handle, no information / experience of users known. Website
runs a demo: www.3dmodelserver.com <http://www.3dmodelserver.com>
* Deskartes
Used to satisfaction of several users, demo downloadable through
www.deskartes.com <http://www.deskartes.com> We received no specified data
on the quality of the generated files. I downloaded a demo with 30 days
license but I haven't had the time to run it yet.
* Compunix
Specialised in file converters, used with much success for several years
according to a reaction from the RP-ML. Website: www.compunix-usa.com
<http://www.compunix-usa.com> No further information received.
* Materialise software
Translator and communicator, see original mail from materialise. Other users
use terms as easy to use, good coherent STL file, including STL fixer,
frequent updates. IGES covers all dialects and entities and can handle
multiple layers. See further information in the mail from materialise. And
www.materialise.be/soft <http://www.materialise.be/soft>
* Brockware
Fast and reliable conversion from IGES to STL, mesh of STL is correct but
less suitable for editing due to thin and small triangles.
* Varimetrix Vision
General purpose CAD program, recommended by a user for fixing and working
with IGES
* POWER SHAPE by Delcam
General purpose CAD program, recommended by a user for fixing and working
with IGES
* CADfix by FEGS Ltd
Promising promo material, no feedback from users yet. www.cadfix.com
<http://www.cadfix.com>
* RP Workbench
Complete engineering workbench for data RP processing, under development at
the university of Bremen, inherent no users info. See text from developer.
www.biba.uni-bremen.de/users/jop/jop.html
<http://www.biba.uni-bremen.de/users/jop/jop.html>
* Trifix / copycad
Lots of options to edit and fix, thin triangles cause stitching garbage.
* Rhino
Can process IGES and STL, generates a very good mesh on STL. No further user
information.
www.rhino3D.com <http://www.rhino3D.com>
* Nendo
* Is a modeller available for $100. It saves obj files which can
easily successfully be converted to STL. at www.nichimen.com
<http://www.nichimen.com> . No further information known.
So far the gathered reactions, any additions are most welcome of course at:
b.kooijmans@ind.tno.nl <mailto:b.kooijmans@ind.tno.nl>
Further pages display the original mails, names have been left out to retain
discretion.
Dear Mr. Kooijmans,
Thank you for your interest in our software for viewing, measuring,
communication and manipulation of 3D CAD data.
View Expert accepts both STL & IGES files, and once the files are saved in
the native DA format, anybody with our FREE viewer can read in these files
in order to continue the communication process.
3Data Expert is an extensive tool for manipulation and conversion of IGES
and STL models. The following are some of the features of View Expert and
3Data Expert:
* viewing STL, IGES & VDA files
* verification of STL, IGES & VDA files
* repair and editing of STL & IGES files
* conversion of IGES & VDA file to STL format
* Boolean operations, adding pins, holes, splitting parts
* positioning and scaling
* reduction of triangle count in STL files
* shelling of STL files
* offsetting of STL files
Please install the software and send us the id in the About Box if you would
like to receive a FREE 30-day license to evaluate any or all of the features
listed above.
Thank you again for your interest in our products. Please do not hesitate to
contact us with any questions or additional requirements. We are looking
forward to hearing from you soon.
Best regards,
Johanna Manai
Sales Assistant, DeskArtes
Hey, you guys,
I'm out here screaming about useable cad. Have you checked out "nendo" at
www.nichimen.com <http://www.nichimen.com> . Its a modeler available for
$100. It saves obj files which can easily succesfully be converted to STL.
With a little prodding this company, I'm sure would drop in an stl file.
$100. Not full fledged CAD but a great great toy. Very fun to play with!!
Bart:
Have you tried any of the file converters offered by www.compunix-usa.com
<http://www.compunix-usa.com> ?
They specialize in file converters and my company has used their prodcuts
with much success for several years.
Good Luck!
Regards,
Hello Bart,
thanks for the fast reply. I will wait for the summary on the rp-ml.
My own experiences belongs to my research work at BIBA. I'm developing a
software system called RP-Workbench, which will be a complete engineering
workbench for RP data preparation. One major feature is the handling of
surface data and their conversion to RP data sets (either facets or direct
slices). Up to now, the systems only works with VDA-FS files, but one of our
project partners is currently working on an IGES interface. As the internal
data structure of our software is similar to the VDA-FS syntax (parametric
polynomal surfaces) the IGES interface will translate the IGES information
to VDA-FS and the system will then read the VDA-FS file. Therefore, our
experience concentrates on the handling of VDA-FS data, but I think most
problems could be compared to IGES.
Our translator first reads the surface description, generates approximated
surface boundaries controlled by user definable tolerances, automatically
and/or interactively merge the unmatched surface boundaries controlled by
user definable tolerances (body healing) and adjusts the surface normals.
The finally generated B-rep solid could then either be triangulated (and
saved as STL, DXF, VRML or OBJ file) or it could be sliced directly without
any former triangulation (and saved as CLI, SLC, SSL, F&S or STD file). The
accuracy of the triangulation as well as the direct slicing could be
controlled by user definable tolerances. Depending on the quality of the
original surface model the quality of the generated models is very good. We
have translated and build hundreds of parts with the software so far and it
works very well. But this procedure does not work automatically in every
case. Especially parts from CATIA (or other older surface modelers) often
show a lot of defects like untrimmed, missing and double surfaces. Our
system could detect untrimmed and double surfaces and the user then have to
decide how to handle this surfaces, which is not always as clear as it seems
to be. In case of missing surfaces it is necessary and even better to go
back to the CAD system and regenerate the affected surface. On the other
hand we had very good experiences with models coming from STRIM and Pro/E.
However, to our experience it is mostly not possible to generate a 100%
closed b-rep solid automatically from the surface model (works only for
simpler parts). In practice we obtain approx. 95%-98% closed models. The
remaining portions could either be handled by interaction (selection of
matching candidates, reduction of edge resolution, elimination or
insertation of boundary vertices etc.) or the defects could be fixed after
triangulation in the facet part of the software (it is not necessary to
match the whole surface model before triangulation). Since the facet
geometry is much simpler than surfaces many problems could be handled
easier. We first use a similar matching routine like in the surface part to
merge unmatched triangle edges. The routine is able to match nearly every
gap or hole (depending on the selected tolerance), but since it is focused
on matching two individual triangle edges (instead of matching boundaries of
a complete surface) the continuity and curvature of the original surfaces
could not be quaranteed along the matching boundary.
Furthermore, you have the possibility to fix bigger defects (holes in the
triangular surface) with a filling algorithm, which triangulates the hole (
instead of merging triangles edges). This procedure is recommended for gaps
with could not be merged up to a tolerance of 0.15 mm. Beside easy to handle
planar holes, sometimes a model could contain complex non-planar holes. It
is not very easy to reconstruct such a missing surface. We use an algorithm
which tills the non-planar hole into several planar regions, which could
then be processed separately. Since their could be hundreds of different
ways how a complex hole could be tilled, the user have to play with some
parameters (planarity tolerance, minimum surface area etc.) to get the
result which would fit best. However, complex holes could be fixed with
this method, but the original intention of the designer could not be
quaranteed. In some cases it is still better to regenerate the missing
surface in the CAD system, but this decision belongs to the user.
For STL fixing we also have used the Magics Software. Both systems (RP
Workbench and Magics) were able to fix almost all STL errors. Problems could
only occure for very complex holes or complex triangle intersections.
However, to our experience matching on the surface level produces better and
smoother continuity along the surface boundaries.
Hope this information will be useful for you.
-- Best regards ...Dear Bart,
Materialise NV has 2 converters for IGES to STL conversion. The first converter is implemented in Magics RP and it allows you to select IGES files and convert them to an STL file according to the applied triangle tolerance parameter. This converter is extremely easy to use in a Windows environment and it offers different extra advantages: 1. The result, an STL file, is directly available for inspection and what is more, if there are defects, you can easily fix them with the Magics STL fixer so that the correct result of the conversion is guaranteed. 2. The converter gets frequently updated which means that all current IGES entities and dialects are covered. 3. Where a lot of converters only display the entities which are stored in layer 1, the Magics IGES module can handle multiple layers at the same time. This means that on some IGES converters an IGES file appears to be empty, however the information is there but it is just stored in different layers.
The second converter can be found in the MAGICS COMMUNICATOR. Communicator is a web based 3D CAD communication tool which also allows import of IGES files. It offers the same ease of use, but in this case the result of the conversion can not be changed anymore. This converter is intended for that reason for visualization of IGES files, although it also allows true IGES to STL conversions. For more information: http://www.materialise.be/soft <http://www.materialise.be/soft> <http://www.materialise.be/soft <http://www.materialise.be/soft> > Kindly,
> What package do you use to generate STL files from a surface or solid model > and are you satisfied?
Our CAD package of choice is CATIA. For STL-Output we use a self-programmed Utility. > If you have a little more time: What is the > quality > of the generated stl-files (overlapping, thin, reversed triangles etc?) > Same question for IGES fixers?
It is as good as the Geomtry being exported. Usually the STL's are error-free, but even a Solid's surface in CATIA is sometimes not 100%. Until now it was never a problem to fix the errors automatic (3D or Magics software) within a minute.
Bart,
We use three programs:
1) Brockware - This product is great for convering IGES to STL if you already know what's contained in the IGES fle and you don't need to make changes before the conversion. It's very fast and very reliable. 2) Deskartes Rapid Tools - In addition to IGES to STL conversion, this product has many tools for modifying the geometry. You can do Booleans, shelling, separating, refining, etc. 3) Varimetrix Vision - This is our general purpose CAD program. In addition ot being a superb Surface and Solid hybrid modeler, it is unsurpassed at reading-in IGES files and working with them. It can perform solid operations, including booleans, filleting, draft, etc., on open surface sets, so there's no need to create a closed volume.
We have doing iges to stl for the last 4 years. We used several high end CAD packages like Pro/E, Strim {Matra}, Surfcam, etc. and STL converters as SolidView and Magic. The easiest way so far has been using a STL converter like SolidView or Magic RP. Comparing the last releases of this to soft we prefer Magic RP since it output a more coherent .stl file. We solid design or closed surface of high end CAD we had no problems. With bad trimmed, overlapping surfaces etc. We had a lot of troubles {garbage in garbage out} with surface CAD design that do not are water tight. The worst nightmare for us are the iges CV files. If you know how to export a clean CV iges, please let us know it.
We have POWER-SHAPE from delcam, but the STL it exports is the same as they generate for the shading and is a very poor algorithm which produces lots of very thin triangles etc. IGES in-and export is oke. Rhino generates nice trianles too but couldn't read Powershape's IGES-es well. Solid works makes excellent STL-files but has a problem stitching the imported IGES to a solid. We use TRIFIX from delcam to fix and stitch STL-s which is satisfactory but we would like the STLs to be generated good right-the-way.
So far the relevant parts of the messages. Thanks to all the persons who took the time to react
Ing. N.M.J.P. Kooijmans. Prototyping / Tooling Engineer Production Development Division Oostsingle 209, P.O. Box 5073 2600 GB Delft, the Netherlands
Phone: +31 15 2608 729 E-mail: B.Kooijmans@ind.tno.nl Fax: +31 15 2608 725
Visit TNO at: http://www.tno.nl/instit/indus/prototyping/ <http://www.tno.nl/instit/indus/prototyping/>
-------Netherlands Organisation for Applied Scientific Research-------
For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
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