View Full Version : Converting SubD to CAD formats?

06-21-2018, 10:24 AM
I was wondering if anyone had a pipeline for converting their models to CAD formats for clients to use as reference layers. I've done it in the past and clients really like it but the process is annoying and expensive.

Current process:
Purchase 1 month of maya.
Export LWO into OBJ
Import OBJ to Maya
In Maya do this: Polygons>SubD>NURBS>export as .iges
Let license of Maya lapse because I do this a few times a year.

I'd love to have a plugin for lightwave to do the SubD>NURBS>IGES process, but I know that's likely not going to happen, so a stand alone program that doesn't cost me $$ every time I want to export. So low yearly fee or one time fee would be great.

Preferred file types:
#1 .iges
#2 .step

Any ideas?


06-21-2018, 11:14 AM
I’ve used Tsplines for Rhino in the past to do this but its not available anymore (thanks Autodesk :( ). You could just hand them the obj file as most CAD software can import that. Next version of Rhino may have the ability to convert polys to nurbs, but it will take some years before its ready. It may be possible that there is a beta version, I don’t know.

06-21-2018, 11:37 AM
Alternatives I am exploring.
SharkCAD Pro 10. It's really expensive, but says it'll convert SubD > NURBS > IGES.
Modo with Power SubD-NURBS plugin. Also expensive but claims to convert SubD > IGES
Blender. https://forum.freecadweb.org/viewtopic.php?t=19252 This is older, so I'm not sure if the process still works. It's free though.

06-21-2018, 03:11 PM
I would start with evaluating the freeship app first. The steps describing Blender you can skip as LW can export obj and also vrml if I remember correct.

06-24-2018, 09:47 PM
Hmm, I know formZ now supports sub-d surfaces and NURBs, and apparently can convert from sub-d to NURBs (http://www.formz.com/manuals/formZ8/formZ_Jr/!SSL!/WebHelp/10860_Subdivision_convert.html). There's a "free" version of formZ as well (not sure if it can do so, though).

If you can post a reasonable sample of the complexity of object you're trying to convert, I can try using formZ to do sub-d -> NURBs -> IGES.

06-25-2018, 05:06 PM
Designsparks mechanical cad, (free if signed up)
Can import obj format, and then right click to convert to solid (not true nurbs)
The problem is however the lack of export options as there are only Amf, dxf, obj, sketchup (skp) Stl
Edited...I can see step export in preference, have to check

Not sure about freecad.