in a weekend.... if you don't take your eyes off of the screen, maybe. it takes a good few weeks to get adjusted to a 2d cad system (with all the different lines, splines, and adjustments you can do, then learning the keyboard commands for them all). then addind an extra dimension to that.... all i can say is have fun.

tho, some systems out there, like QuickCad, are designed for people who don't have a lot of cad experience, and can usually be picked up pretty quickly (hence the name). but they usually take longer to do the same kinds of things, and don't have all the cool shortcuts.

Best of luck.