Gentlemen, you have converted me! I am now gathering the bits and pieces to make a CNC pick-and-place machine for populating PCBs. I couldn't even estimate the number of PCBs I have built by hand over the years, but now I'm looking forward to leaning back in my chair and watching a robot do all the work.

After that will come the various robotics for machining die-cast cases, fitting the PCBs in them, and testing the end product. Time scale to be in production is six months, but for the first time in my life there are no commercial pressures on me so if it takes longer, who cares?

By the way, surveying the CAD scene there seems to be plenty of 2D and 2.5D software around at sensible prices, but there doesn't seem to be so much 3D. How important / useful is 3D? Do people here use it? If you do, could you live without it?

My grateful thanks to all who have responded so magnificently to a stupid newbie's questions! I now understand your enthusiasm for the subject. :)