I have, at various times, given my cheap 3D solid modelling program (sounds like Otto Kad) fits trying to develop fairly complex shapes. The same shapes were quite easy to define, draw, and communicate to a machinist using DG and a 2D CAD modeller (or, heck, coulda done it with a napkin and a straight edge too). DG is a useful tool, and not that hard to use once you get the idea. As a sometimes analyst, there is no better way sometimes to figger out the angles than by developing the true view from scratch...