Free 3D Design Program for Mechanical Engineers

[TS656577]

I'm currently a mechanical engineer and in the required courses is a 3D design program class where we design things such as 3d engines and other things. I know they probably use expensive programs, but is there a free, fairly easy to use program out there that I can download and use on my home pc?

 

[Timbuqtu]

Try http://www.blender.org"

 

[mgb_phys]

Blender is an excellent animation tool but doesn't work in the same way as parametric CAD systems like Autocad Inventor or ProE.
There used to be a free version of ProE called pro-desktop, it's discontinued but might be out there somewhere. Can you get access to a student copy of Autocad ?

 

[fargoth]

how about BRL-CAD?

have a look http://my.brlcad.org/d/about"

 

[mgb_phys]

The trouble is that there are two main approaches
Blender and most rendering/animation tools build up models from simpler shapes or curves. It looks at quick glance that BRL-cad does this, it was popular in the early 3d packages like autocad3d

Autocad Inventor/ProE/Cadestra etc 3D mechanical cad packages use constraints. You sketch an outline of a part, then add constraints such as these two sides are parallel, this hole is in the middle etc. When there exactly enough constraints the part becomes a model. This ensures that the finished 3D model is buildable - animation tools will let you create Escher style models that cannot exist.

Learning this constraint sketching technique is important if you are doing mechanical cad. Although the shape based system is quicker to produce simple models.
The animation tools also generaly lack the ability to do dimensioning, parts lists, obstruction/fit checks etc.

 

[sam207]

What about maya? Is it free or what?

 

[fargoth]

well, you're right.
I use SolidWorks to make the models i need built (with constraints), but it's not a cheap program (although not so expansive either compared to other programs in its field).
and if i need some very specific tool I program it using Open Cascade - a free CAD library for c++ (which has been ported to tcl, python and c# too) - but for a non-programmer, and for general use, I can't recommend it.

 

[mgb_phys]

Open Cascade

Nice - I hadn't seen that before.
There is also VTK a free 3d vis library - it's aimed more at 3d voxel type data like cat scans or fluid models but is very nice and free.

 

[fargoth]

Nice - I hadn't seen that before.
There is also VTK a free 3d vis library - it's aimed more at 3d voxel type data like cat scans or fluid models but is very nice and free.

yes, I've programmed with VTK a little, but it's not a tool for model design - as you've said, its a visualization tool kit to view data in 3d, it lacks CAD capabilities.
it has good documentation though, if you buy the two books about it.

 

[las3rjock]

Visit the Autodesk Student Community ( http://students.autodesk.com ). A school-issued email address is the only requirement to register for the site, and once you're registered, you can download a free and full-featured version of Autodesk Inventor, which works just like SolidWorks, ProEngineer, Unigraphics NX, etc.

 

[binzing]

Sketchup is ok for toodling around, I have it and blender. I'd like a good cad as well, where I can like make actual scale drawings by lke punching in numbers if that's possible.