[Tristan Lall]

Originally Posted by rmmlg

We just got AutoCAD from FIRST (as I'm sure all the rest of you have too) and I became rather proficient with Inventor last year. I have used AutoCAD 2002 in Mechanical Drawing class in order to model a house.

Fine, but AutoCAD and Inventor are intended for different things. There is no Inventor Architectural; once you realize that they serve different purposes, the reason for this becomes obvious.

Originally Posted by rmmlg

I like many things about AutoCAD better than Inventor (namely the command line) so I would like to switch over. I noticed that AutoCAD doesn't appear to have parts and assemblies like Inventor does, but instead has layers (I'm assuming that layers are analagous to ipt files in some way).

Layers can be analogous to parts, if you happen to design things that way, but certainly that's not valid in general. Inventor is based upon assemblies of 3D solid models; AutoCAD is typically used for orthographic projections and planar layouts--nobody in their right mind uses AutoCAD's 3D mode for actual design work (it exists to simplify export of AutoCAD data into other, 3D-based programs). AutoCAD simply isn't designed to accomodate engineering data for parts themselves (mass, volume, material, etc.) [Edit: There are ways, but they are very rudimentary...try setting regions, and getting the enclosed area, then multiplying by the thickness and density--clearly this won't work most of the time], nor is it particularly well-suited to parametric modelling (AutoCAD's associative dimensions are a pale shadow--and even Inventor isn't great for this).

Originally Posted by rmmlg

Does anyone have suggestions for switching from Inventor to AutoCAD?

Don't?

If you really want to use AutoCAD's 3D mode, but still retain some sort of Inventor capability (and I assume you do, otherwise, why would you ask how to make the switch, instead of just doing it, and donating your 25+ licences to another worthy FIRST team), you can export to some convienient format, and import it into the other program. I've never tried this, but I should hope that both support 3D .dxf files. Inventor may not be able to read and assemble these, though.

Actually, if you're looking to make engineering drawings, AutoCAD has a better interface for complex tasks, but at the cost of all of the parametric information. (I like drawings that try to update themselves when the model changes, and you should too!*) If it's just a quick drawing, do it in Inventor by choosing your sketch dimensions carefully, then creating an .idw file with the required views and dimensions. It can be much, much faster than going through AutoCAD.

*Except when their geometry fails to resolve. Then it's a pain.