It is a strange fact that I have never scratchbuilt a flat car before. I clearly remember the Kalmbach book, Easy to Build Model Railroad Freight Cars, recommending that you should start out with a flat and work your way up to house cars; of course, I also clearly remember ignoring that advice and leaping in on a dustbin-fated hopper. However, what makes it stranger is that I’ve had the project rolling around in my head for years.
Over the course of many bike rides, and much laying awake at night, I had come up with a plan for making flat cars so that a load built for one car could slip into the stake pockets of another of the same class. The theory revolves around setting the stake pockets precisely using an alignment jig.
To avoid gluing pockets to jig, I made the jig from brass. It turns out that 3/64″ square brass almost fits into the Grandt Line single-bolt pockets that are a match for my cars. A little filing on the pegs’ faces makes them slip into the pockets nicely.
I only need a jig long enough for half the car as I can flip it to do the other half. The spacing between the middle two pockets is different on the 333-series cars anyway.