Hi Capt Chrysler, I hope you don't mind my jumping in here too to get some advice. I've always just sketched drawings of projects out and I've photographed those and posted that here to convey an idea (often get some laughs too). I'm thinking I should learn basic cad. Would I be wise to learn on 2D and move to 3D once I've gotten my feet wet or should I just jump in with 3D from the get go?
I have experience with video editing and compositing SW and photoshop and the like so not a total newbie with SW. I'm on a mac.
While they are both computer aided drafting, technically, they are two different beasts. IMO, if you are going to be in the CAD world to any extent, it is valuable to know at least the fundamentals of both types. However, there really isn't much benefit to learning 2D before 3D, as the process is very different.
The difference is how you develop and create finished drawings. Most 3D software is parametric, and uses models defined by parameters attached after sketching to generate the drawings used for manufacturing. Plain 2D CAD, however, requires accurate input as the drawing is created, much like regular pencil and paper. Then the drawing is simply put in a title block and sent out.
Parametric modeling software is superior for developing a design, as it allows changes to be made that cascade through a feature tree, and is very quick and efficient at tweaking dimensions and shapes. 2D cad would require a sometimes time consuming re-draw to get the same result. 3D also has useful time saving tools, like sheet metal or weldment design. All of which are possible with 2D, just not as quickly.
However, 2D cad still rules the roost for quick shape generation for sheet cutting. You can bang out all kinds of simple brackets, covers, caps and things like that for a CNC plasma or laser. It also is very useful for making simple sketches that can be used for scale comparison, or cleaning up overly complex drawings that will eventually be imported into Solidworks.
A student license is a great way to get your feet wet in a more expensive CAD.
Draftsight is my favorite free 2D, because it is basically a free version of AutoCAD, and is very powerful for being free. Made by Dassault Systems, publisher of Solidworks, it is like a big middle finger to AutoDesk, saying "we're going to take your flagship program and give it away for free" . Which given what negative things Autodesk is doing to the CAD world right now makes me giggle.