A few weeks ago, I finally decided what I wanted to do with this shabby Lionel handcar that I picked up at my last York trip. I have designed and built another unusual rail vehicle seldom seen in O Scale-- the Pennsylvania Railroad's custom made Street Tractor! The PRR built several of these vehicles in their Juniata shops back in the 1910s. They were in service in Baltimore through the 1940s, being gradually replaced with more modern vehicles in the 1950s and 1960s. Here is a link to an article where you can read more about these interesting early road-rail vehicles.
The project began with dismantling the handcar so I could take measurements off the frame. There were two screws and one rivet that had to come off. Here's what the motor frame looks like once you pull off the top section and pop off the little gear for the gandy-dancer movement. I kept the two body screws so I could reuse them to attach the new body.
Using a photograph of an original tractor and the dimensions taken from the handcar motor frame, I created a new virtual model in Fusion 360. I had to deviate from the prototype in a few areas to make it fit, but it came together after a couple of test prints.
My biggest concern was the pulling power of the handcar motor. Modern Lionel handcars are powered by a little bitty 0.5A can motor and a very simple worm drive powering only one axle. The motor isn't even screwed into the frame, it's roughly held in place by a shelf on the body. I made sure to clean and lubricate the motor drive before I started.
By carefully adjusting the body screws to put just the right amount of pressure on the motor, I was able to comfortably pull 1 boxcar at about 13V on my small O54 conventional loop.
After one final design revision to adjust the screw hole placement, I finally had the body fit to my liking. The conversion kit consists of 2 resin pieces (the body and the muffer on the roof) and 2 filament pieces (the couplers). The couplers are held onto the buffers by screws threaded in from underneath.
With the CAD design out of the way, it was time to build the whole thing. I started by painting the model with some nice Rustoleum 2x Forest Green.
After this came decals and handrails. I used my usual 0.050" wire for handrails and rummaged up some scrap PRR decals that I had lying around in the shop.
After taping in some clear plastic window glass, the first Street Tractor was fully assembled and ready to roll.
Here is the finished Street Tractor running on my layout.
A future project will be to add some form of a motor control board (the model is awfully small for full command control!) and LED lighting for the headlights. Until then, happy holidays!