Monday, July 4, 2016

Odd Finds in Dusty Drawers

Part of doing research - historical or otherwise - is the luck of the draw. Who knows what got saved, or what you’ll find if you search in that odd dusty box?

Back in January, I was up at the California State Railroad Museum for another day of research before our annual Bay Area Layout Design and Operations meet. (Thanks to the upcoming Super Bowl booking all the hotels, we got the chance to wander a little farther than usual.) I had a rough idea of documents I wanted to see - some car records for the Hart gondolas, blueprints for the CS-35A flat cars in preparation to refine the design, and drawings for track arrangements at various places in San Jose.

The CSRM is a great research library; the staff are helpful, the rules aren't draconian, and the materials are well-organized and unique. I’ve looked at a lot of freight car plans there over the last year, and I’m still amazed what got saved. There were still holes in the historical record; I might find some blueprints for SP’s Battleship gondolas, but might not find details identifying how the cars were assembled. I might find drawings of New Almaden after they tore down the station in the 1930’s, but little on the arrangement of the tracks in the town’s heyday. It all depended on what SP manager decided to save from the files… or what drawings a railfan pulled out of a dumpster.

I’ve been particularly interested in the arrangement of the brake system for those Hart gondolas I’ve been selling. Personally, the exact arrangement of the brake gear is not the biggest concern for me. For my own models, I’m willing to do something that seems reasonable; as long as the cars look plausible and run well, I’m happy. But when I’m selling the cars, I know that many others do want to get the brake gear precise, and expect that I’ve done the research to make the cars accurate.

The initial kit instructions described a plausible arrangement for the brake gear based on photos and some guesses about arrangements - my best information at the time. However, I’ve always been bugged that I didn’t understand the cars better. Without another source for information, I was stuck.

So take in the scene. I’ve driven two and a half hours up to Sacramento on Friday morning, grabbed a sandwich in Old Sacramento, and I’ve been sitting in the library at the museum since it opened at 1:00. It’s a bit after 4:00 on a Friday afternoon.; the library closes in maybe 45 minutes. I’ve found all the material I’ve wanted, and I’m trying to decide whether to head over early to the Old Spaghetti Factory to socialize with a bunch of other model railroaders, or spend a bit more time looking for anything interesting. I stand up, stretch my legs, and go wandering around the reading room to see what else might be there, and find a three ring binder that’s an index to a bunch of Union Pacific drawings. The index is all handwritten, printed with fat letters done apparently written with a Sharpie and photocopied a couple times; I'm guessing it's a genuine handwritten artifact from the U.P. shop foreman.

I’m ready to discount the contents as modern stuff outside my interests, but I ask Kara, the librarian anyway. “These look interesting; is there any chance I can see these drawings?”

“Oh, we got those years ago. The index never got computerized, and I don’t remember the last time anyone looked at those. The microfilm is over in this cabinet here.” She shows about six file drawers, packed tightly with old-fashioned microfilm rolls. We pick one roll that looks promising, Kara shows how the microfilm loads, and I start looking.

The roll turns out to be a random mix of technical drawings for freight cars, mostly not from my era. I dive in like I’m in Minority Report, quickly checking each image to see if it’s interesting, and learning how much to tap the “forward” button to advance to the next image in a single step. Tap, look, tap, look, tap, look, tap, maybe two or three seconds per image. Part of my speed is just disinterest, but I also realize I’m on a deadline to finish before the library closes.

At 4:50 p.m., I hit pay dirt.

It turns out in 1919, the Union Pacific drew four sheets of drawings for an “Air Brake Folio”, describing the mechanics of the air brake system on a bunch of recent freight cars. For each car, the folio gave some details about braking power and force, formulas for calculating hand brake force, and schematic drawings describing exactly what the brake system looked like. Somehow, those sheets got saved by the UP into the 1970’s when they dumped them but not before microfilming them.

And sheet three includes drawings for the brake systems on Union Pacific’s Hart gondolas.

So I pull out my cell phone and quickly take photos of the interesting bits of the drawing. I also manage to find a couple drawings showing how the Union Pacific lettered their gondolas a few images later. I finished at 5:02. With profuse apologies and thank yous to the staff, I rewind the microfilm and head out the door.

I’ve put details of the brake system up on the Dry Creek Models blog. The drawings give more accurate details for the cars - length of the different rods, and how the brake rodding snakes between the truss supports. One surprising fact is that the Union Pacific cars have an obvious difference from the SP cars. On the SP cars, the brake wheel pulled the piston of the brake cylinder directly - a rod and chain go straight from the piston end over to the brake wheel. On the UP cars, the brake wheel was at the opposite end of the car, and a pulley reversed the direction of the brake chain. According to the Air Brake Folio, UP apparently did this on many of its freight cars (including their version of the H-50-5 hopper and B-50-13 boxcar). If anyone knows why the UP did this, I’d be interested in hearing.

Discovering these drawings is all part of the magic of research - whether for model railroads, or for local history, or for academic, formal history, or even for garage sales. I’m really grateful for all the material that has been indexed or listed in finding aids, for it means I can spot interesting things from my desk at home. However, part of the fun of re-discovering the past is searching in the places that haven’t been curated, indexed, or pored-over by others. I’ve heard that same fun of discovery from a friend searching for depression-era glassware at Goodwill, and from historians like Alex Wellerstein searching the National Archives for the history of nuclear weapons.

And no matter how fun the search might be, we’ll also learn exactly which way the brake cylinder should point on our freight cars.

Oh, if you're curious, here is my original guess about the brake gear layout (as found in the kit instructions), and the brake gear as suggested by the UP engineering drawing:

Air brake drawing from Union Pacific Railroad’s s “Air Brake Folio”, dated March 5, 1919, book 430, drawing 5242-30) , from the California State Railroad Museum.


  1. So, now we wonder: How close was your "this looks plausible" initial arrangement to the one on the actual datasheet?

    1. Hi, Brooks,
      My original attempt was pretty far off. The current kit documentation shows my "simplified" brake rigging. The big differences are only one brake lever instead of the correct two, and the missing connecting rod passing through the gussets (or behind the trusses, I'm still not sure which).

      Full kit documentation here:

      The whole question of how accurate to make the brake gear starts hitting the question of why we're building railroad models in the first place. Some folks might say we want to make the models accurate just because our goal is to make accurate models. (That's why we're not building models of P-51s with Russian air force markings.) The crowd that builds models for contests would insist on the accuracy because that's what the contests value. I'm always a bit torn - I'm 3d printing these cars so I can have a bunch on my garage layout, and part of that is figuring out how to make decent models quickly without being too obsessed about details. However, I also realize I'm building (and selling) these cars as a way to share a bit of freight car history, and I'd like to be as accurate as possible as I share the story of these cars.

  2. And thanks for the question. I've updated this post to include the before and after sketches for the brake gear.