[eloff]

But that's just the thing, you aren't limited so much by time and cost. The time is proportional to the size of what you're printing, and the cost to the amount of materials and time involved. None of which says much about what the design must look like. You design it on the computer, look at in 3D on the screen as much as you like, and print a scaled model, if you must.

You don't need to print up a full-scale prototype anymore than you would do that with a traditional design and construction technique.