For some reason, I’ve always been interested in this kit and always wanted to improve on the basic kit. After deciding on a diorama scene to show it doing its role rather than just displayed with some figures, I thought I would go all the way and do a full interior as best as I can with the info available, ie, this book…
My first step was to separate out the two sides and add the running gear. I then cut out the area for the internal engine exhaust to sit, which is covered externally. The alignment between the rear door and hull floor is incorrect in the model so the floor needed to be removed and adding internal equipment will be easier this way. Plenty of pin marks to fill…
My first focus will be the front transmission inside the front hull section which connects the front of the engine…
… to the two front track sprockets with the steering done by two levers which I assume operate brake mechanisms. There are no pictures of this transmission, just the external housing and a small area under the steering lever…
I’d really like to hear all ideas about the possible nature of the transmission for this vehicle. Obviously, I can only approximate this and other parts of the build based on the info available, but hearing ideas and opinions will be of great help.
The German halftracks, Sd.Kfz. 250 and 251, were produced in far greater numbers which makes me believe that they were “better” (operating, maintaining, repairing, fuel consumption, production cost, whatever).
If the 254 had been an efficient scout, command, troop transport, artillery traktor or some other usage then it would have been produced in large series instead of the Sd.Kfz. 250.
The conditions on the eastern front led to the design of the RSO which can be compared to the tracked mode of the 254.
My conclusion: The wheeled mode was performed better by other vehicles,
the tracked mode was performed better by other vehicles, the mixed mode (switching from wheels to tracks and vice versa) usage was performed better by the various halftracks.
It’s a very interesting vehicle. I remember reading a story about a young mechanic who had one after the war and used it as a tow truck . He used it to escape East Germany. Story went that he never deployed the wheels ever so the guards thought it was just slow etc. well one night he deployed those wheels and sped through the roadblocks with his whole family…
So this basic diagram is how it appears the vehicle operates for track or wheel motion. To the left of the driver is a small drive selector lever which enables the selection of either drive via a transfer case (same principle as a 4WD vehicle) - front drive for track operation via front sprockets and rear drive for rear-wheel drive - plus neutral.
When the driver selects wheels up or down using the drive selector lever, this also operates the mechanism to move the wheels up or down via a different shaft (red) and this functions to operate two shafts (green) which turn a torsion bar running on the outside of each side to both wheel suspension units.
So this is a bit of progress so far. It takes a long time to study the various images in the Nuts and Bolts book, many hours already.
In a nutshell, you can see I lined the inside for a better fit with top part of hull and cover all the holes and pin marks, and filled the front left area where a drive shaft from the front differential will go. Just general tidying really. Also, the front hull structure in the kit extends too far at the top and the bottom so I cut it accordingly. The radiator sits on three supports on top of the front hull area and the diff is directly beneath it protruding from the front hull area so the hull needs to be modified.
I will unify the white plasticard and putty with Tamiya putty and glue mix, as well as a texture to the inside of the front hull piece.
Other things were drilling out the small holes for the suspension attachment points and crank start hole which is more realistic. BTW, I’m starting at the front as the positioning of the radiator will help with better gauging where the engine sits.
The radiator has a twin fan set up like the one shown next to it below, so I have to recreate that first and then make a water cooler on top which attaches to the engine and can be seen through the top engine hatch. It will be old school as I don’t have a 3D printer. After that, I’ll think about how to do the front diff, engine and gear box as nothing similar exists.
Despite the Nuts and Bolts book being excellent and I wouldn’t get very far without it, it has a few small errors which I’ll flag just in case anyone else wants to build a more complete model.
The front hull does not extend this far back into the body. The three small brackets on it are roughly where the radiator sits and pictures in the reference book show the hull ending just back from there.
This support frame does not exist as the lower half of the engine sits in the left side of this point.
The shaft to the return rollers goes across here as can be seen in the engine image above.
This shaft is not possible as it would run across above the floor level, which it does not. The only one seen above floor level is the front return roller, which is great as it gives a height level indication for building in the engine and gearbox.