very flimsy.. http://st2.depositphotos.com/4316461/10549/i/950/depositphotos_105498050-Old-wooden-coach-wheel-near.jpg here's a rough wooden wheel to show you the shape, spoke number, and bulk you should go for, for the front wheels. the back one should be more of a wide drum like on the steam rollers.
http://www.hiveworkshop.com/attachments/tzar-tank-1-png.240989/