I am working on making an N-scale Model Power USRA 2-8-2 more mid 1950s NKP-like, and one thing that stands out on most of these engines is that the smokebox front has flying number boards, a headlight and a Mars light. The model has a one-piece smokebox front casting with the headlight cast into it. It occurs to me that the easiest way to modify the front would be to replace it entirely with one that has the desired details, and Shapeways looks like a way to make one.
I've no experience as a CAD designer, and don't want to buy design design software at this point. I know that Shapeways lists some free software as useful for designing and submitting models, but also know that not all free software packages have similar capabilities.
Any recommendations for a project like this?
George