I've actually considered doing them on shapeways, but I can't figure out a simple and reliable way to get power off of them. I have a set from Miniatures by Eric, they are nice but FYI the hole for the bolster is offset - not centered. I had not thought of replacing the center piece with styrene, this solves a lot of problems!
Yep. You really might consider using a strip of PC board instead. The tricky part is getting it all to stay
together. You could solder it all, but then if you ever want to get the wheelsets out, you have to flex things
and pray You can greatly alleviate this by filing the inside bottom of the where the axle point goes in,
so it doesn't take much of a bend of the sideframe to let the wheelset drop right out. You have to be careful not
to overdo it, so the wheelsets aren't annoyingly just falling out by themselves all the time!
Anyway, if you do this, you can solder the sideframes to the PC board strip. It's stiffer.
Then you file a slit through
the copper PC board to get rid of the short, solder two phosphor bronze wires about 1/2" long to each side of the PC board, and those protrude up into the tender through some slots. Now,, you can solder fine flexible wire to them,
or go whole way to have them wipe on the underside of flexible posphor bronze strips that you mount
in the tender floor.
I did this trick with brass import freight car trucks and it works quite well.
You
could use styrene and just solder wires right to the insides of the truck frames too.
