Just for the sake of conversation, were there any engines in real life that had truck mounted couplers? Also why did manufacturers for year leave all roof walks and brake wheels black?
http://www.northeast.railfan.net/diesel60.html Alco's double-engine diesel unit for UP (who else would want such a thing?)
I guess it depends upon what you call a "truck" Most of those long diesels mentioned, plus the Baldwin Centipedes, (to add one from my era) and vertually all heavy straight electric motors, had either span bolsters, or modified pedestal subframes connected with articulation joints. I can't think of one of where the couplers were "truck-mounted". I can think of dozens where the couplers were mounted to the end sills of the span bolsters or the pedestal sub-frames, causing the couplers to swing on the curves independently of the superstructure of the locomotive. Technically, the front engine bed of most articulated steam locos have a coupler mounted to the pilot end of a sub-frame that pivots intependently of the boiler when entering a curve. But is that a "truck"? HA! while typing, I thought of one that comes as close as any to being "truck-mounted......." That would be the rear coupler of a 3-truck Shay. The 3rd truck has a rudimentary frame so it can support the rear tank, is drawbar-connected at the cab end, and caries the rear coupler in an abbreviated end sill at the rear. The tank and 3rd truck will stand independently if disconnected, because there is no kingpin. The entire works - truck, tank and sills, are rigidly assembled into a single unit. [ August 15, 2005, 01:22 PM: Message edited by: LongTrain ]
For modellers' purposes, couplers on span bolsters are truck-mounted. That is, manufacturers don't have a choice of where to put them.
