This blog will be slower than my previous two construction blogs, that of the Tyco/Mantua Pacific conversion to a Southern Railway Ps-4, and the conversion of an MDC/Roundhouse 2-8-0 Consolidation into Tallullah Falls Railroad #78. This is because I am very busy with work, and have a lot less time available. Also because this will be my first DCC locomotive: in fact, #78 will also be converted to DCC operation.
TFRR #74 was Southern Railways' #202 Mogul 2-6-0, built by Rogers in 1889. It was acquired by the TFRR to replace a previous #74 scrapped in the mid 1940's. Once more, the MDC model is very close to the prototype. In fact, the sand dome will not have to be relocated in this case, as it was for #78. #74 had its original wood cab throughout its entire service life. This cab is identical to the MDC/Roundhouse Old-Timer cab, so this will be retained, resulting in a very different appearance from the #78 project.
The principal changes in the conversion of the model to #74 appearance will be reducing the size of the drivers from the kit-supplied 60"+ "high-stepping" drivers to a size closer to the prototype 54" drivers. I was able to find a used set of Tyco/Mantua 51" drivers with their hex-headed screws for around $5.00. I believe they are from the 4-6-0 kit. In preliminary fitting, the pinion gear of the flangeless center driver needed to be slid a bit to locomotive right (starboard). After doing that and mounting the drivers, the mesh with the model's reduction gear appears to be perfect. I have not tested under power yet, only by turning the open frame motor's armature. There is no binding or slop in the movement. The trailing pair needs to be moved up to the same spacing as the front to center pair. This will mean that at least one pair or rods will have to be re-made, using the shorter pair as a pattern.
I replaced the pony truck wheelset with the remaining pair of 30" 9-spoked wheels left over from the #78 build. This is from a NWSL set, # 47226-4 . It is to be tested if the stock rods can be used for the front driver set. The driver centerline is the same even though wheel diameter is greatly different, but is the eccentricity is the same (I have not measured yet) the length should be identical. A test by placing the rods over the wheels seems to confirm that the length is the same, and so the front rods will be useable. As mentioned before, they will be the pattern for the new pair of back rods. There needs to be some light reaming of the pin holes to accommodate the brass screws' blind shaft, which is a larger diameter than the model's stock plastic pressure-fit pins. The pilot will have to be cut off and replaced, as the lower height causes it to be at track level. This is fine, as #74 has a more projected cow catcher. I have to study the valve gear hanger, as it also comes pretty low to the track.
I am awaiting the DCC decoder to arrive before beginning the conversion in earnest. I have looked into my brass parts bin and selected most of what I will need. Missing are the headlight and tender light, but the kit's original "modern version" plastic ones are good enough and a LOT easier to drill than the brass ones!
So here goes again...! Please be patient with the slower speed of the conversion. I promise it will result in a unique piece of motive power, and I hope some of what you see might cause you to chime in with better ways to accomplish the same task. This will be a learning experience for me, with your help.
