Baldwin DR-series prime movers had a bad reputation for performance on many railroads, and cash-conscious carriers like the Chicago North Western and Pittsburgh's Union Railroad came up with innovative solutions to rebuild their aging Baldwins with more reliable EMD powerplants. The Chicago North Western Railroad performed EMD rebuilds on two of their locomotives, the #1506 and the #1504. Lionel, MTH, Atlas and all the rest have never bothered to make these unique locomotives in O Scale, and few save a handful of master kitbashers have even attempted a MTH AS616 conversion project.... until now!
I was commissioned by a longtime C&NW railfan to design a resin rebody kit for a MTH Baldwin AS616. I started by dismantling the donor locomotive and making a CAD mockup of the frame, motors and board stacks.
The body took shape as 3 sections: cab and short hood, center long hood, and nose long hood. There are two body seams which are supported by overlapping tabs.
One slight deviation from the prototype on the C&NW rebuild was the need to add the "toolboxes" on the short hood side of the cab. Many photos seem to suggest these were removed during the rebuilds (although #1504 seems to have had them at one point). The Baldwin donor frame has the smoke and reverse unit switches in these locations, and moving them would add unnecessary complexity to the kit.
It took three revisions of models to dial in all the dimensions, which included making the short hood a little taller to clear the top of the motor flywheel. I added mounting holes to reuse the handrails from the MTH Baldwin's body, which thanks to the toolboxes fit without any modifications. The end platform railings are held in place between the new body and the locomotive frame.
The GP handrails are a little trickier to attach. They would have to be snipped just short of the cab and then rebent to fit into the new locations. I didn't want to permanently alter the railings I was borrowing from a GP shell so I stopped at a feasibility check.
Here's what the finished body shell looks like bolted to the frame. It's held together with 4 machine screws (#4-40 in the cab and #6-32 in the center of the long hood) plus a couple of alignment tabs. This is unpainted UV-cured resin that you are looking at.
Here's a view from the front. There's a bit of play in the sections so you can get a suitable fit on the frame.
Here's a video of the C&NW Baldwin rebuild running on the conventional loop on my layout.
Now the Chicago North Western wasn't the only railroad that had their old Baldwins rebuilt with EMD prime movers. The Union Railroad in Pittsburgh built their own version which they nicknamed "Buffaloes" after the step-up in the long hood.
I had to make a significant compromise in the Buffalo's design since the scale short hood wouldn't fit over the front can motor's flywheel. The cab is now about 3/8" longer than it should be. I have the capability to make the scale cab.
Here's the Buffalo shell with the pieces slid together. I was able to reuse a lot of the interior fitments from the C&NW rebuilds to save significant design time.
Here are the three pieces set side by side of the Buffalo.
Finally, here's the URR Buffalo on the track!
Here's a view from the long hood side.
And of course it runs too!
I wish to thank all of my commissioners, customers, well-wishers and fellow Forumites for your support of my sole proprietorship adventure. I always wanted to make my own trains and toys and I can now say that I have achieved that lifetime goal. Keep them on the rails, fellow Forumites!
* edit for corrected typos
