A total of 21 hours of work and but well worth it: this is my favorite now, and the #1 locomotive on my layout, taking pride of place as the "owner" of my biggest mainline loop: a Legacy ATSF 2900 class Northern.
2921 was a scale, early PS1 MTH Northern that had sound noticeably poorer than anything else I typically have on the layout, and that ran only so-so (I run only in conventional and it was okay but not great, particularly not liking to go really slow, really smoothly). The MTH body is grafted onto a Legacy 3759 chassis and all electronics from the Legacy 3759 tender has been moved to the 2921 tender (had to make a new chassis): that is Lionel running gear in the loco, Lionel electronics in the tender, and the Lionel wireless connection between them (on a custom-made drawbar, but everything you see on the outside is either MTH or scratch). In the real world, both locos had the same size drivers (80") and wheelbase (21' 3"), so this conversion made sense from a physical standpoint.
All ATSF Northerns were handsome but I think the 2900 class was just a tad better looking than any other Northern - or than any other steam locomotive ever made, for that matter.
Size matters in Northerns (and tenders). In the picture above 3751 was slightly behind 2921 and camera perspective made it appear smaller than it is relative to 2921. Here I've adjusted the 3751 image from so you can see their relative size. In the real world the 2900 class was not quite two feet longer than the 3751, but MTH used the casting from their 5012 class for their 2900, so this puppy is about a scale four feet longer: all the better to make for a big, brawny look! And the big tender doesn't hurt the "awesomeness factor" either.
Converting the MTH body and the Lionel Chassis to fit together required lots of cutting and grinding, including repeated use of a sabre saw to hack away metal, but took only five hours. The tender required three times that long to complete. It did not have center pickups, so I moved those from 3759's tender to 2921's trucks. I ended up making a completely new chassis with a two-speaker grill in the center (the MTH chassis had the single speaker over one truck - then re-positioning all electronics). Biggest problem, though, was that plastic enclosure over the speakers that Lionel provided did not want to fit in the MTH tender (interference from two mounted screw towers) and I spent four hours just modifying it to fit. this was necessary because without that enclosure the sound is terrible! I custom - made a new drawbar to give the same 11/16 inch clearance between loco and tender I measured on 3751.
You can see a bit of the motor where I had to cut out body interference in the MT chassis.
The rear truck from the MTH loco would not co-exist with the Lionel chassis not matter how hard I tried, and the Lionel 3759 rear truck looked far too scrawny for the 2900 - particularly too short of wheelbase and just not substantial enough. This is a truck from the unpowered end of an MPC-era diesel that I found in my parts pin. It is just the right size and shape and it looks good in place (and fits and runs well, too). Yeah, not the right type of truck, but the sides (everything you see) are just cast facades that screw right off - eventually I will make custom side facades patterned after the real thing.
I know it will pull hard because it the loco itself weights about 9 ounces more than 3759 did and it would pull 30+ cars with no problem. I have not asked 2921 to pull anything beyond these 13 slogan cars and a scale caboose - yet. Oh what a fantastic locomotive!
Definitely not PS1 sound even if the microphone on my cheap little Nikon butchers its richness. This puppy is running in conventional smoothly at speeds far below what any PS1 loco ever would do smoothly for me.
) your not afraid to do it. I would say more often than not your insanity pays off. Good job.
