The last completed project of 2011 was this pair of Alco S-2 switchers. These both started life as Model Power HO models, which were based on an older AHM model (the “Alco 1000”). This conversion could be done with the original AHM drive with the vertical motor, it is an easy OO conversion but not a great drive. It is geared too high and only has four wheel electrical pickup.

Another key thing to note again is that that this model was marketed as HO but have overscale bodies and trucks that from the side especially scale out very well for 1/76. It is underscale for OO but visually works pretty well, and is a conversion that can be done without a lot of heroic effort.

I wanted to do a pair of these and I am very happy with the end result. The conversion is pretty straightforward. It took two different train shows to locate the models but I found two good examples with the horizontal motor setup. Step one was completely tearing down the models to repaint the frame and body. I used the original motor and the front truck of the Model Power models and modified the drive truck area to accept an Athearn drive truck, selected as it not only is simple to convert to OO but also because it has better gears and picks up power. Using the drive involved opening up the frame area to accept the larger drive truck mechanism (there is plenty of room in the cab to do this easily), making a new mounting bolster out of rectangular plastic tube (glued in the pocket where the original truck mounting was), fitting the drive, and modifying the cab weight to clear the back of the new drive. I also added more weight above the drive truck as there is extra room, leaving the model weighted just a bit heavier than it was from the factory.

The second photo shows the underside of one of the models, giving a clear view of the drive modifications. These I have described in previous articles as well. I used the original front truck but modified it so the sideframes would clear the wheelsets (widened out on the original axle) and modified the other sideframes to mount on a ground down remnant of the original Athearn sideframe. Power is picked up from all eight wheels, and the driveline itself uses mostly Athearn parts (a couple shortened) but with the original AHM part that was on the gear tower shifted over to the original motor to make it all work.

The main compromises are the model is a bit narrow over the walkways and the wheelsets are too small in diameter. These defects are not particularly visible and are totally acceptable to me in the context of now I have a pair of models that are closely matched, that run very smoothly at prototypical speeds, and have enough power together to pull a good string of cars. Right now to begin the year I have them running with “modern” cars from the 1980s but they look great with equipment from the 1940s era on up. Plus, if anything goes wrong with the drives I can easily fix them and I only spent something like $60 total on both models! Retro-modeling is easy on the budget.

I would certainly do this conversion again and very likely will at some point, perhaps next time keeping the factory paint job. In particular, the first HO locomotive I ever purchased was the AHM ATSF version of this model; at some point I would like to get one of those set up for OO. But a more likely project will be to create an OO scale Alco RSD-1 (or MRS-1) from these body parts and the drive of an Athearn FM Trainmaster. It is great to get projects done but also great to be thinking ahead to the next one.

Finally, looking ahead for this site, I will have to slow down on posting for probably the next several months. Professionally I hit one of the busiest times of my year. I will try to have something new up every week or two, and trust that regular readers can find much of interest in the site with a bit of digging around.

UPDATE: To make the conversion a bit clearer, this final photo is of the drive with the body removed. Focusing in on the drive specifically, the first plastic part off the motor was originally on the gear tower side of the Model Power drive. The rest of the drive line is Athearn but with parts shortened to make it all fit. Wires are soldered on to the Athearn drive as well to facilitate 8 wheel pick up. Also visible in the photo are the modified weights. The bottom line being this model now runs quite smoothly, the conversion is well worth the effort.