I've been using Blender to design stuff, but while it is good for characters and objects, it's not good for mechanical parts. Does anyone know of a good free (maybe opensource) CAD for designing mechanical parts?
I've looked around, and there is no open-source solution for real mechanical design. There are free CAD programs out there that will work for hobby projects, but nothing too complicated. try e-machine shop to get an idea. If you need real CAD you can get it for about 10% of the cost of a high-end package and still get the exact same functionality, without some specialist features you probably won't need anyway (you probably won't be making molds). I picked up Alibre Design and it works great for most tasks.
I use Blender for mechanical modelling. When I first tried mechanical modelling in Blender I found it very hard. You have to do things slightly differently to how you would in something like Autocad. You often need to make temporary geometry as a construction aid. Learn how to use shift-S for positioning the 3D cursor and moving/scaling relative to the 3D cursor. This tutorial helped me out :- http://www.rab3d.com/rab3d/tutorial/608/tutorial_608-1.html Regards, Ian.
What about the Maya Educational use only demo? If you print something it'll say demo on it, and you may not be able to export to required formats, but might get you something that you can switch to blender or truespace to be able to export into a required format.
I found this qcad. I work at the office on autocad, and qcad look very similiar. Its open source http://www.ribbonsoft.com/qcad.html
It's not open source! You can download a demo or buy it. The demo version terminates after 10 minutes.
just to clarify, the Qcad demo shuts itself down every 10 minutes. Apparantly that's the only difference compared to the full version. It is a 2D CAD program tho. I didn't realise until I tried using the demo.