I try to prototype like I vote – early and often. The sooner I can see what the materials/volumes/finishes are going to do, the better design decisions I can make.
The Canyon Table will have a map of the topography formed by the Green and Colorado Rivers. It is a location that is important to me, as well as a metaphor for our journeys through life, their twists, and confluences with others.
3D modeling programs have their place, and as an artist I find them useful for a quick, inexpensive gut check as to sizes and shapes that might work well. Google Sketchup is intuitive and has a ton of on-line support. After that stage, I have yet to find a good replacement for actually trying scraps of the material I will use.