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Top-down design


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Hello friends

I request some info on

1.Top-down design approach

2.Bottom-up design approach

3.Reverse Engineering

4.Concurrent Engineering me understand the concepts of the above w.r.t Pro/Engineer

we can use Pro/SCANTOOLS

1. repairing bad IGES geometry (big dihedral instead of tangency, gaps between surfaces that can not be zipped) by creating pattern of datum curves and exporting these curves to IGES. After that we use scantools for best fitting of new style surfaces to imported IGES (low density in scantools) curves. What you get there is smaller number of surfaces, better manufacturability. What you loose is that you get an approximation of original surfaces. Results are very good.

2. When making dieface tool one wants to have as small number of surfaces as possible an more important extends (usually greater than 5 mm) on the edge of the sheetmetal part. If the geometry is imported, then it is almost impossible to quickly extend the surfaces. Clasical methods (extending existing boundary curves and creating surfaces by boundaries) results in poor geometry which isusually nontangent. What we do is create quite dense grid of datum curves on the part and not so dense grid of curves which are extended from part out for let us say 30-40 mm and are tangent to original part. Both grids are used in scantools for building a good approximation (less than 0.05 mm) to original part.

3. Reverse engineering.

If you have organic shapes then use a software that makes untrimmer surfaces out of point cloud (Geomagic, Paraform,...).

If you want to make shapes like ball, cone, extrude,... out of point cloud with best fitting of basic shapes on it, you should wait for Pro/E Wildfire restyling. It is nice.
Hi all,

My Email account is flooded with emails asking for emails. It is tough for me to send to everyone. i have given it to lot of people. So ask all the people on this group and they will send u one.

Bye and have a nice day u all

Pawan Arora
If you received Pawan's tutorial, would you mind emailing me?

joemoak+mcadcentral (at) gmail (dot) com

Is there any reason someone does not host it and post a link to
it? If someone sends it to me, I will post it on our
website with a link to it for the rest of the people who are asking.

erich (at)
Hi all,

I hav been busy lately but i expect to reply you guys with the tutorial shortly and i will try to put it somewhere that it is accessible to you. Thanks Erich for the advice or i will ask you for that.


Pawan Arora


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