Alibre Design – A Great Cad Program
It has a very good sketch mode with parametric dimensioning that stays intimately connected to each object, and you can re-dimension at will. It was a bit of a learning curve, but there are a lot of vids that help a lot, and its well worth the time.
In Alibre you make each individual part, precisely extrude to 3d and then assemble all the parts in the assembly mode. It is very precise, and individual parts stay distinct (unlike Google Sketchup). Later you can generate a STL file to machine or extrude the part – this capability comes with the basic program.
A very cool feature is the ability to choose constraints so parts mate or align in precise ways, and can be moved (gantries sliding etc), its very powerful.
You can export the individual parts to dimensioned drawings with multiple views. I just wish it would have the option to print oversize drawings tiled (on multiple pages), and import/export other CAD file formats in the Personal edition.
Alibre has over 90 training videos available that seem to cover about every possible operation, and that’s important to me. I got a 3-D mouse: 3Dconnexion, that makes it much easier to navigate.