Three rail GMC / All Nation switcher questions

Not sure, I've seen many with a front to back mounted motor powering all four axles each with a worm drive and also seen some with a vertical motor on one truck.  Not sure I've seen one with chain drive although maybe on the single truck it would be used?  I've got two I am piecing together from parts, but not a complete on just yet.

PS, The two rail scale guys will probably have some better insight on this since that was it's original market in the '40's and 50's.

CharlieS posted:

Recently I picked up a three rail switcher on EBay. The seller did not identify a brand, it looks like it is either a GMC switcher or All Nation.
I don't know how to tell the difference. Can somebody tell me?

The GMC switcher became the All Nation product; they all have GMC on the casting inside since the molds got transferred when the line was bought by A-N

I think I read somewhere that GMC used a worm drive, while All Nation used a chain drive. Not sure.

At least 4 different drives were available dating from the early 50's.  Vertical drive single truck drive; horizontal drive that that was single or dual truck drives that were available with straight cut gears, beveled/angle gears, and then a chain drive in a tower transfer over each truck similar to the original Weaver drive.

Also, the bell is bent, Is the casting still available?

Probably could be found on secondary market or eBay of by posting on O Scale Yard Sale.

Probably more direct would be to just buy a nicer brass casting from Precision Scale.

Dennis and MWB: Thank you for the information.

I have a second Switcher that came in a GMC box that looks to be almost identical, with the exception of the collector assembly. The one I just purchased has a Lionel pickup mounted to the dummy truck. Otherwise it looks the same.

I also have a GMC two rail kit, which was never assembled. Unfortunately it is missing the whole motor truck.

Attached are some photos of my recent acquisition.