Narrow Gauge Road Engine – 6 axle – part 1
I was talking to my friend Andrew Gillette one day about the possibility of using my Prusa i3 MK3 3D printer to create modern style On30 Road Engines. This isn’t anything new – On30 itself developed from using HO mechanisms with O scale shells to create narrow gauge ‘on the cheap’.
We had found examples of EMD, GE and ALCO built locomotives for the South American narrow gauge market and thought we could come up with something similar. To this end Andrew supplied me with an Athearn (HO) SD40-2.
Narrow Gauge Road Engine – 6 axle – part 2
The first step was to replicate the inside to the SD40-2 shell to create a ‘glove’ that would fit over the mechanism just as the factory shell does. The narrow gauge shell then would be built over this.
Narrow Gauge Road Engine – 6 axle – part 3
I was happily working on the CAD for the shell that would fit over the mechanism – but at some point realized I needed to create the mechanism itself in CAD – to get at least an idea of where to ‘slice and dice’.
I downloaded a SD40-2 model from 3D Warehouse just for the trucks and gas tank. Everything else I created from measurements of the Athearn mechanism. I didn’t try to get the drawing exact .. just wanted the shapes ‘good nuff’.