David…After learning the AutoDesk Inventor 7 Software…I would have to disagree with you to a point…there is no way a two dimensional pencil sketch is going to communicated a complex three dimensional object as effectively as a 3 dimensional parametric modeling program. To be able to rotate an object and look at it from any angle, to be able to display it as a opaque surface, or translucent surface, the possibilities are endless…And you end up with a fully functional scaled drawing that can be easily modified (as you pointed out) not a freehand sketch that will have to be redrawn to scale. Much, if not all the tooling trial and error is eliminated. Individual objects can be created, fitted together, and animated to check for correct interaction and fit before it ever comes off the computer screen. If the program is used correctly it will flag, and block you from continuing an error. You will have to correct the entry error before continuing, or defeat this feature, in order to move forward.

For someone who has drawn with conventional drawing instruments all my life, I can say without a doubt that “exploring the possibilities” with CAD makes things so much faster and precise, that one can hardly equate the two. The resistance seems to come from the fact that in every college level CAD class I have ever taken, there is always two or three high school kids that smoke every one in there ability to grasp the concept of CAD and execute the drawings. I had one 50-year-old guy kiddingly say he would like to break the fingers of the little 17-year-old girl at the station next to him, her hands were a blur and she had the complex 3D assignment done before he had 5% of his finished.

Well...Back to the custom house plan I am drawing for a client…with a pencil…ahhh…if I could afford a copy of Auto Cad I would have been done days ago…it was either the Cat or the software…LOL...what can I say?

Bob