An old favourite is obeche wood - which is harder than balsa, but still easy to carve. Some folks make blocks of Milliput and carve them, or make plastic profiles filled with Milliput in between. Laminated plastic, or pespex are fine - the list goes on! It really is just finding the best material for the item you're building.
A "professional" material is a solid resin which you can buy in architects model suppliers - the stuff I've used is beige colour and has no grain. It's beautiful to work with, but quite expensive and the big downer is - the dust causes cancer!! Wear a serious mask for this stuff - not the little "tissue-paper" decorators' jobs.
Hope this helps
All the best
Rowan| |)
