processing of stl file in pro engineer

[rnithinmanohar]

I have created 3d model in Auto desk 123d Catch, I imported that model in Pro-e which was in Stl format. I am unable to process it i.e I can not perform operations like Merge, Extrude,etc.. I have uploaded the model in Stl formet, please help me

[JonathanHodgson]

STL is a pretty nasty format for transferring CAD models - it approximates the model as surface triangles, much like an FEA mesh. For some reason it's preferred by STL and SLA '3D printers', but it loses a lot of information from the original CAD.

Try STEP (.stp), or if that isn't available, IGES (.igs).

Ah, sorry, I've just seen that it's come from 123D Catch (software which constructs a 3D model of an object from a series of photos from different angles). In that case, I'm not sure there's much you can do - I've found before that imported STL elements are neither surfaces nor solids, so as far as I know there's nothing you can do with them.

Happy to be proved wrong...

[MartinHanak]

Hello,

I found the following topic in Creo 2.0 Help.

About Working with Imported Faceted Geometry

The tessellated files that are imported from STL, VRML, STEP, and MEDUSA contain faceted geometry.
You can use the imported faceted data in Creo Parametric to:
• Calculate mass properties and measurements such as distance, length, angle, and area.
• Create datum features by referencing the faces, edges, and vertices of the faceted data.

This means that STL geometry cannot be used as reference for Merge, Extrude,etc...

Martin Hanak

[neomechanikos]

Restyle module is what you are after. Take a look at this video:

http://communities.ptc.com/videos/3505

[neomechanikos]

If you don't have the restyle module, you could also re-create it from scratch by creating points at each vertex and drawing curves through them to create boundry blends but I hear that there are other forms of torture that are more effective.

[Patriot_1776]

AutoCAD should be able to export a STEP file (or if need be, IGES), use that instead. These export files are all still "dumb" files, but at least they're not faceted.

[dschenken]

It's from 123D Catch. Autodesk product, but not AutoCAD.

[Patriot_1776]

Should still be able to export a STEP or at least IGES file.

Also, from what I seem to remember (though I could be wrong), the STL file is made a little oversize, with the flats of the tesselation being tangent to the true surfaces, with the points of the triangles being oversized. If I remember, that' so when you sanded down the resultant SLA (or FDM etc.) model to remove the high points you got the true size.

[dschenken]

123D Catch processes a series of pictures** and matches the bit maps to back-solve for the surface they most likey were on. The result is a pointcloud file that is wrapped with a texture map that's projected onto the triangles. STL is just the triangles alone. It also puts out OBJ, which is STL with the bitmap wrapping. It has it's own format that you can use to buy things from Autodesk through their fabrication services.

There could be a tool from STL to STEP - A google search turned up FreeCAD as a possible vector. I'd also consider using Meshlab to fix the STL; simplify and smoothing.

**Not entirely true - the Client part of 123D Catch organizes and transmits the photos to Autodesk servers where the processing takes place and then retrieves the computed results. By itself, 123D Catch is useless.