Naperville Door Prize 2: Chicago Burlington & Quincy FM-11/11A Flatcar, 2000 Prototype Modelers Seminar Kit

Time for another Naperville Door Prize Project. In 2000 Sunshine Models surprised attendees not with a conversion kit (like the MoPac box shown here) but with the basic components for an entire CB&Q flat car.
The model is based on the CB&Q's FM-11 flat. The railroad built 850 of these "home-built" cars in its Galesburg (IL) shops between 1928-30 - indications are building flatcars like these were a great way to keep the shop crews employed during the Great Depression. Two virtually identical classes were built - the FM-11s (91000-91249) and the FM-11As - numbered 91250-91849. The one obvious difference was the trucks - the FM-11s had Andrews trucks while the FM-11As were equipped with AAR cast steel sideframe trucks (better known to modelers by the brand-name "Bettendorf"). In 1953, some of the cars were converted for early TOFC service.
A request for prototype photos on the Steam Era Freight Car list led to this one from Rob Adams - the instructions didn't include a prototype picture, so the project was stalled until I could find one: what I can tell the load is a pair of military trailers - I think they are generators but they're hidden beneath the tarp. Don't plan (at this point) to model the load - I'll be happy to get the flat built!
The door prize includes the basic parts needed to build the car - I'll need to supply the various detail parts.
The first step was to clean the resin parts in warm soapy water and then rinse them well. Assembly was extremely straightforward – remove the side stake pockets from the resin sheet, install a few additional resin parts including the coupler boxes, and drill holes and install two grabs on each end and one of each corner on the sides of the car.

I build most of my freight cars to run on the layout, not to enter a contest. This means I leave off the parts and underbody details that (1) interfere with operation or (2) can't be seen profile with the car sitting on the track. I might ignore Rule 2 sometimes, but never break, or bend Rule 1.
Flatcars are tricky since you have to get enough weight to get them to track reliably. You could weight a flat car by adding a heavy load, but it’s nice to have an empty car that tracks reliably.
I used A-Line "BB" style lead weights for this. The photo shows about half the weight in place. - I apply a thick coat of Canopy Glue to the "voids" between the center sill and cross stringers above the trucks. Then I dropped the "BBs" into the glue. I also filled the space between the two centersill halves with Canopy Glue and added more weight.
One assembly trick that you might find useful on a resin kit is this method for removing smaller details from the resin flash "sheet.". Before you spend hours anxiously trimming away the resin “flash” from the smaller detail pieces with a hobby knife try sanding it away.

I remove these pieces (in this case the 26 stake pocket castings on this car) by cutting about 3 or 4 stake pockets out from the main sheet. Then I gently rub the piece of sandpaper (in this case I'm using a sanding stick, since it's what I could find. Move the part in a gentle circular motion until the resin flash gets extremely thin – and you’ll find the pieces will pop right out!