I'm using SolidWorks. It is two pieces. I wanted to make it in one piece, but that would be well over a day of printing and a boat load of support material. I'm not quite ready to go there yet. I started with a revolved section in the middle, then added an arm with an airfoil like cross section. I placed the wing where I wanted it and then lofted between the arm profile and the wing profile. Then I did a circular array to make it into three wings. I should have turned the edge visibility off.
The solidity is quite high at 0.8, but I figured the airfoils needed some chord to act like wings and the higher solidity might be better for a smaller turbine. My thought was to make a kit, or have some downloadable files. Then make a booklet talking about how VAWTs work etc. Maybe the VAWT could charge a supercapacitor and light an LED or something like that. The base would have slots for the coil, a small box for electronics, and an adapter so it could be mounted on some electrical conduit.