The best way to paint models, rail road or other, is with an air brush. Second best is to “rattle can” it with cans of spray paint. Neither of these are recommended indoor activities without some method of venting the fumes.
So I built a small spray booth.
I already had a ventilation fan that I was using to assist the venting on my Glowforge laser cutter, so I figured that it could pull double duty and vent the spray booth also. So all I had to do was make a booth.
I had some large sheets of double thick cardboard that I had saved from some boxes, and I had a sanding dust collector hood that I was not using so all I needed was a furnace filter and a sketch.
The dust collector hood was 16″ x 13″, but they don’t make a filter that size. So I bought one that was 14″ x 20″ and made do.
A quick sketch, a bunch of cutting and taping and viola! A spray booth.
Here are some build photos.