G scale / 1/32 scale wheels and tool

This is a wheel design and alignment tool for wheels for G scale garden railways.
I set this up to help design the 20mm wheels for my tram http://www.thingiverse.com/thing:1379253,
and for the 30mm wheels for the 12 ton coal wagon http://www.thingiverse.com/thing:1572391

There are some instructions in text form in sketches in the 23D file, but essentially this is a G1MRA standard wheel profile with an axle centreline clearly defined. You then select and "revolve" the profile around the