Comparing 3d Printed Models Against Kits of the Past

When I talk about those Hart gondolas I made a while back, I like to highlight how the models represent freight cars that haven’t been done accurately in the past. There’s no resin kits or brass kits for Hart gondolas, let alone for SP's own version. However, combing through old Walthers catalogs will show two Hart gondola kits: the craftsman kits from Silver Streak in the 1960’s, and Train Miniature’s plastic shake-the-box kit from the 1970’s. Both are good for their time, but we can do a lot better in the 2010’s. How much better? I picked up examples of both the Silver Streak and Train Miniature cars at a train show a couple weeks back. Let's compare them against the 3d printed model and see how forty years of technology has helped model building. (Click on any of the photos for a higher resolution version.)

Let’s first look at the Silver Streak kit. For the time, this is a neat kit. It has the underframe trusses from the real car, brake cylinder mounted on the side of the car, and matches the SP cars with 8 spaces between posts on either side. Just like the modernized SP cars, the Silver Streak Car has grab irons on each end supported by a short vertical piece of wood.

However, the kit lacks the car sill and floor you'd see on the real cars. Instead, it has the car side boards going all the way down to the bottom edge of the car. It’s also missing all the door hardware; the real cars had castings at the bottom of each post, but that’s a pretty tiny detail to include. The modeler who built this kit didn’t quite get the bulkheads at the correct location - they should line up with the outer post.

The model’s a little coarse with 6x6 strip wood serving for the top rail and for the posts, but it’s a fair tradeoff for intermediate modelers building their first car. It’s nice to see the board detail on the inside faces of each side. Overall, the car is a bit oversize, with the sides measuring almost five feet high compared to three on the real car.

Here’s the Train Miniature car. Again, it looks like it got inspired by the Southern Pacific cars that would have been seen in the 1930’s and 1940’s… or they just copied the Silver Streak car. The car has the correct eight spaces between posts. The grab irons arrangement doesn't match any of the real cars, though. More importantly, the trusses are pushed out to be even with the sides - definitely not how the real car was built, and a detail that hides one of the neat details of the Hart design. Like the Silver Streak car, Train-Miniature left out the car floor visible on the sides. Again, the car sides are taller than they should be - partially out of scale, and partially fallout from removing the side sill.

And finally, here’s one of my models. I pulled out one of my “original” cars just to highlight the detail. 3d printing gives us a lot of advantages, including the ability to throw in all that detail for the door hinges , the door latch mechanisms on the posts, and the various bolts all over the model. The truss is lighter than the Silver Streak car, we can see the car side frame and floor sticking out beyond the car sides.

Here’s all three from the top: Silver Streak on the left, the Train Miniature, then the 3d printed model. The Silver Streak car did correctly model the sloping hopper. It’s not perfect; this kit shows the hopper as incorrectly extending up along the bulkheads on each end. But I’m pleased to see they included the supports that ran through the hopper, even if they’re not quite at the right location. There’s no detail on the hopper doors, but then that’s a pretty tiny detail.

The Train Miniature kit’s hopper is hidden by the load, but that brake cylinder and brake gear in each end is completely wrong for the car, and misses the fact that those partitions were meant to be removable so the car could be used as a typical gondola.

And finally, for the 3d printed version. We see the braces running through the hopper (with the notch to hold the 4x10 that supports the doors when closed. We see the end bulkheads definitely look removable. On the far end of the car, you also might see the hinged apron that allowed running a plow through all the cars - a detail that wouldn’t be needed on either of the other modernized cars, but does highlight how 3d printing lets us throw all that sort of detail on the car.

Finally, here’s the underside of each car - Silver Streak on the left, mine in the middle, Train-Miniature on the right. This photo highlights how the other two cars are a bit oversized compared with the actual cars. Both Silver Streak and Train Miniature made some parts oversized (like the trusses) and also placed the trusses differently to make the car easier to manufacture. Both also had to lose some of the interesting detail: braces for the trusses, side sills, etc. in order to make an economical and easy to build kit.

All in all, the Silver Streak and Train Miniature kits are fine for both their time and for what they’re intended for. They had to design parts to be manufacturable. Train-Miniature moved the trusses out to the car edges so they could be injection molded in one piece. Silver Streak made the trusses thicker to survive manufacturing and clumsy fingers, and left off detail on the hopper so the fiddly shape could be made in cardstock. Both kits needed oversized parts for easier assembly, dropped details to keep part counts low or permit injection molding, and did the best they could from the photos and plans they could find.

The 3d printed model gets to benefit from being 30 years in the future. I had access to the SP blueprints which the earlier manufacturers may not have had. 3d printing meant I could make parts closer to scale, and could easily add details and embossing that would have fouled up molds and part ejection. 3d printing also allowed me to refine the models, and quickly make variants: doors up vs. doors down, or the modernized cars without the side dump doors. If I found some railroad back east had a similar car but with a minor tweak, I could make that too. That's a luxury that anyone doing injection molding doesn't have. Cutting a new mold is an expensive, start-from-square-one sort of action. Anyone trying to run a business would want to cut those molds once, and getting a detail wrong isn't enough of a reason. Doing a different model requires a different set of molds; again it isn't worth doing unless you're going to sell a ton of the new design.

All three models also show how model building's changed. Silver Streak's kit dates from the craftsman kit era, and a time when you could run a reasonable model railroad manufacturer out of your garage. As long as you could cast white metal and cut strip wood, you could sell a model railroad kit. Because of the lack of good models, if you had an even partially realistic model, you'd have a hit. Train Miniature dates from the heyday of small-scale plastic kit manufacturers. You need a lot more skill and equipment to make injection molded parts, and even more to print the car sides. Worse, the effort needed to cut those molds meant you had to sell thousands of cars - great for a forty foot boxcar, but not so good for an odd misfit maintenance-of-way car.

3d printing gets us back to those garage days. My Hart gondolas were, after all, made in a garage. (Or at least I wash the extra resin off the printed models in the garage; the printer stays inside to stay away from dust and cold.) And yet the models still have some pretty impressive detail - approaching resin kits, but certainly better than the kits we saw in the 60's and 70's. We'll see more 3d printed models like these in the coming years, and it'll be great to see the prototypes that folks find interesting enough to manufacture in their garages.

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In case you'd like a Hart gondola for your Southern Pacific, Union Pacific, or Pacific Electric layout, I've still got 3d printed kits available. Check out photos, prices, and ordering details over at Dry Creek Models site.

Mystery Project

Hmmmm, I wonder what I'm working on next?

Movie Night XXVIII: Things You Ought to Know About San Jose

History San Jose has apparently been busy. Their History San Jose channel on YouTube has a bunch of new videos and interviews. They also have a pair of promotional videos from the 'teens and twenties, one focused on San Jose and the other on Santa Clara County, both in the same YouTube movie. The first half - the Santa Clara County half - is the more interesting one, showing both the operations at the George Hyde packing house and cannery in Campbell, and an apricot plant pit which I suspect is >Sewall Brown's plant at Vasona. The George Hyde videos start around 11:50, there's a scene showing loading a sulfur house around 17:00. Processing apricot pits starts at 18:00. There's two men shoveling pits from a huge pile, which might explain why the Sewall Brown fire in 1958

At some point, I'm going to have to build that office at the Hyde Cannery; having the video, with the horse-drawn wagons crossing in front of, should be a great starting point.

Movie Night XXVII: The Track-Pull Tractor Survived

Earlier this year when I reported on the Bean Spray Track-Pull Tractors, I'll admit I didn't think the tractors had changed the world. Even if one of the tractor startup guys had spoken at a Bean Spray employee all-hands about how "Our Tractor" would change the market, there wasn't much evidence that the tractor had much of an impact. Sure, Jim McCollough did another startup with a similar tractor in the 1930's. Sure, Alf Johnson was still testing tractor designs into the 1950's. But it's not like Bean Spray, and later Food Machinery Corporation ever built more tricycle tractors... right?

YouTube proved me wrong. It appears the Track-Pull design influenced Bean Spray products for years afterwards. Food Machinery Corporation, the name for the company after multipler mergers, was selling a similar three wheel design as late as 1945. This 1945 tractor isn't the same design: it uses rubber tires rather than a Caterpillar track, the engine is front and center instead of on one side, and the tractor is surprisingly tiny compared to the tractors that rolled down Julian Street in 1918. But it's still the same, with a similar fork supporting the two wheels, and similar huge wheels to control steering. I suspect it was a great tractor for a small orchard, or for cleaning up a large yard.

1945 Food Machinery Corporation tractor for sale. $6K OBO.

1945 Food Machinery Corporation tractor for sale. Part 2

For a crazy Sunnyvale tractor startup, it's pretty neat to hear their design was still in production 30 years later. A bunch of us out here in Silicon Valley can't claim such a victory.

Market Street: The Train Departure Board

Short shameful confession time: I built the Market Street layout because it was easier to build than a video game.

A non-trivial bit of my inspiration for the Market Street layout came from the railway switching games made by SIAM Railway Simulations. These mostly-British prototype games provide accurate simulations either of a station or for dispatching a long set of track. The station simulations put you in the role of the tower man and switcher at anything from the end of a country branch to the busy through station at Crewe. The dispatch sections include British settings (Scottish Highland line) as well as realistic versions of Tehachapi Pass, either in the 1920’s or the 1960’s. I’ve played some samples and bought other games.

SIAM's samples page lets you get a taste of the games by downloading demonstration, reduced versions of their simulations. The samples include dispatching the Highland line and Tehachapi Pass, and handling switching in the stations at Crewe and Penzance. The Tehachapi dispatching game gave me a great appreciation for getting trains over Tehachapi Pass in the steam era.

Penzance, 1987 game from SIAM Railway Simulations

Of course, I wanted to try some more American prototypes - handling the traffic coming and going from the Oakland Pier, perhaps. Or why not the San Jose Market Street station? I got a fair way through making an iPad game so I could switch those places, but I found it difficult to control all the switch engines and car movements I wanted to include. After enough tries, I found myself asking "so what would a layout set up like one of these games look like?

So, I’ve built the layout, and I've got an answer to that question.

However, to make the layout operate like the game, I need to know what trains need to come and go. More importantly, if the layout is being exhibited, I want folks to see the names of the trains coming and going so they can understand the sheer number of trains that could be handled in the 1920’s, even if the station was a creaky old Victorian barn.

Suddenly, that way-too-large display on the Raspberry Pi has a use.

Snippet of departure board. Click here to try it out for real.

My inspiration was a European-style flip-card station sign; it’s not quite prototypical for the era, but anyone who’s been in a large train station has seen one of these, so showing a listing of trains should both inform and hint at the sheer number of trains they’re seeing.

And luckily, making such a sign is easy. One of the neat habits of programmers these days is to share programs they’ve written so others can use those programs. A friendly guy named Paul Cuthbertson liked the idea of drawing flip-style departure boards, and based on an inspiring article, went off and wrote a web page to draw one.

Now, I need more than just the departure board graphics for the Market Street layout. I need a sped-up fast clock to show the current simulated time on the railroad, for the compressed track plan means trains won’t take as long to move around as on the real thing. I’ll need a way to control the board when trains arrive and leave. I’ll need a way to manage problems - backing off accidental train departures, or stopping the clock in terms of problems.

I took Paul’s code and created this departure board for San Jose Market Street. (See this Github project for the source code itself.) Pressing a number key (1-9) causes the nth train to move to its next state; a train that’s on its way will go to “arriving” on the first press, then “arrived” on the second, then will be removed from the board on the third.

Paul’s card-flipping web page turns out to require a lot of computing horsepower to flip through all 26 characters for each change. The poor little Raspberry Pi, being the size of a credit card, couldn't keep up. Instead, I changed the program so that the board only performs 6 flips per letter, instead of flipping though the whole alphabet like the real flip board.

So now, when I set up the layout, I just need to set the box containing the DCC electronics somewhere both the audience and operator can see. The stationmaster can use a keyboard to advance the departure board as trains arrive and leave. The operators know what trains they're building; the audience gets an understanding of how easily they could commute from San Jose to San Francisco (or Salinas) in 1928.

And I get a modular layout that's inspired by a video game.

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The modern practice of sharing sample code and reusable libraries is a great part of modern programming culture. Great thanks to Paul Cuthbertson for the core of the departure board code!

If the departure board idea might work for your layout, download the sources from GitHub and customize it for your own use. Drop me a note if you find it useful!

Market Street: Electronics and DCC

From the start, I knew I wanted the Market Street layout to have multiple operators working in parallel: switch crews making up and breaking up trains at the station, road engineers coming from the roundhouse, and taking a train out, and freight crews switching the cannery and packing house on the layout. That meant I needed to choose a DCC system for controlling the trains, and I needed to decide what kinds of throttles to use. There were two obvious choices: I could go with Digitrax, the standard for Free-Mo modules, or I could use the same system I had at home - EasyDCC. Neither was attractive. I’m not fond of the Digitrax system; I’ve always had trouble understanding how to use their controls, and have seen too many cases where an errant button press disabled a throttle. EasyDCC would allow me to reuse my existing throttles, but I’d still need to buy a new command station and booster, find an enclosure for both, and then wire all the modules with coax to allow wired throttles to be plugged in around the layout.

Another engineer running a train on the Silicon Valley Freemo-N layout with a phone

Luckily, I was reminded of the local Silicon Valley Freemo-N group. They’d set up their dozen modules (most based on Bay Area scenes) at the 2011 NMRA convention up in Sacramento. When I stopped by to check out the layout, Dave asked if I wanted to run a train. “Sure, but I don’t have a throttle.” “Doesn’t matter,” he replied. “You’ve got a phone - just install WiThrottle.” They were using the iPhone-based WiThrottle, all talking to some random command station connected to a computer. I downloaded the app, and within a few minutes was running a streamliner across their layout.

Fast forward to last year. At the Bakersfield NMRA convention, one of the vendors had the SPROG 3 - a tiny DCC booster and command station that can power smaller layouts. It could be driven by the dirt cheap Raspberry Pi computers and the JMRI software, making for a full DCC system in less space than a cigar box. This seemed like the perfect choice - wireless throttles for the layout meant no wires for a throttle bus. Operators came with their own throttles, so I didn’t need to shell out hundreds for throttles. It could all fit in some tiny box.

Back: Electronics

Front: Monitor

The Sprog / Raspberry Pi plan won. The Raspberry Pi is a full Linux computer; with a keyboard, mouse, and monitor, it could do anything a big computer could (though a bit slower). I wandered over to Fry’s to pick up the Pi ($50). At the same time, I picked up a cheap flat panel monitor with an HDMI plug; the cheapest, at $99, was a 22 inch display - bigger than I expected. It turns out smaller monitors are speciality items now. That monitor set a minimum size for the electronics box.

With the monitor and electronics, I made a plywood box to hold them all in - the monitor set just inside, facing one way, and electronics the other. The box also contains the power strip, extension cables to reach the modules, and power for switch machines - all nice and compact, and easy to transport. Once it’s plugged in, I can use the monitor to start up JMRI and the command station; with some quick clicks on my phone, I’m running a train. All I need to do now is get some additional plywood to make lids for both halves of the box, and I’ll be all set.

Interesting aside: my nephew came over a couple weeks back and wanted to see my trains. The big layout was a mess, so I laid the Market Street modules on the floor, plugged things in, and we ran trains. When we went back inside, he beamed. "Mommy, we ran trains with a phone!"

Now, that 22 inch monitor is too large to use just for starting up JMRI; check out our next episode to hear what else I can do on that screen.

My Yardmaster Has a +4 Rulebook of Smiting

When I was a kid, I played a fair amount of Dungeons and Dragons.  At its core, D&D is interactive, co-operative storytelling.  You get a bunch of folks together around a table; one person (the “game master”) describes a situation (usually something dramatic from a fantasy novel involving saving the village from a dragon, or breaking into the Thieves’ Guild, or exploring an underground labyrinth full of monsters and treasure). You each describe what your character does, and the gamemaster describes what happens. At its best, it's like writing an adventure novel on the fly.

Dungeons and Dragons - the initial version - was originally created by war gamers. That lineage shows up as lots of statistics and lots of dice. How much damage can my fighter take before he’s disabled? How much extra damage does my extra-good sword give? What saving throw must I roll to avoid being turned to stone by a medusa? The randomness adds to the fun of role-playing, but it's easy for the dice-rolling to take over.  Worse, some folks start thinking the points are what matters rather than the story.  Min-max'ers start making decisions on the game based on the probabilities, acting out of character in order to get the best results.  “Why rescue the princess? It won't give me enough experience to reach level 7.” Munchkins - the stereotypical kid playing only to score more than their buddies - ignore the puzzles and atmosphere in order to kick in the door, kill the monsters, and collect a +16 vorpal sword.

Dungeons and Dragons is a good forty years old now.  (Note to self: keep an eye out for retirement communities with active gaming groups).  Those forty years of game play also means that role playing games have evolved. The latest versions of Dungeons and Dragons still have voluminous rule books, odd dice, and lots of mathematical tables to decide whether your thief can climb to the top of the castle wall. Other games go much more towards the story telling. One of the more extreme examples, The Extraordinary Adventures of Baron von Munchausen, has the players pretend to be the famous Baron von Munchausen of tall-tales fame; each tries to tell a story to outdo the others in the 17th century German tavern…. er, sitting around the table.

And some games stress the interactive storytelling but still have some of those random mechanics. One example is Fate Core. In Fate Core, you still create an alter-ego, and catalog down some of that character’s attributes on a “character sheet”. However, unlike Dungeons and Dragons, you generally use words instead of numbers. You choose a subset of skills that your character is good at (“Very good at athletics and investigation, poor at deceiving.”) You name aspects of your character - one liners - naming both how you generally respond, and an obvious weakness. (“Thief with a heart of gold”, “always jumps in to help the underdog”, “afraid of zombies”). Fate Core uses a simpler mechanic for deciding if you succeed, with simple dice with pluses and minuses for the random angle, and a range of success where you get to narrate the result.  Most importantly, the Fate Core rules includes the simple statement:

“Both players and gamemasters have a secondary job: make everyone around you look awesome. Fate is best as a collaborative endeavor, with everyone sharing ideas and looking for opportunities to make the events as entertaining as possible… Fate works best when you use it to tell stories about people who are proactive, competent, and pragmatic. A game about librarians spending all their time among dusty tomes and learning things isn’t Fate. A game about librarians using forgotten knowledge to save the world is... Characters in a game of Fate always lead dramatic lives. The stakes are always high for them, both in terms of what they have to deal with in their world, and what they're dealing with in the six inches of space between their ears.”

After all, isn't that what we want in fantasy stories? Conan the Barbarian fighting off the invading hordes? Fafhrd and the Grey Mouser thwarting the evil Overlord? A conflicted Batman deciding whether to go after the Joker? Academic psychologists defeating the Blatant Beast in the world of Spencer’s Faerie Queene?

Wil Wheaton’s Tabletop show on YouTube shows what an actual game is like; if I’ve made you curious, go check it out.

But this blog is about model railroading.

I’ve said before that model railroad operation is pretty close to roleplaying - a bunch of us come together in a scenario planned by someone else, and try to tell a story about a day on the railroad.  Switchlists and train sheets give some of the war-gaming randomness.  But we also have a much different mission than Fate Core.  We don't want drama and excitement - we want to be recreating the action of the model railroad in a day-to-day, get-it-done model. We’re coming together to get the jobs done and keep the trains moving.

I think of it as more than a game; I’d like folks to get an appreciation of working on the railroad in the 1930s - what the jobs were like, how busy the railroad was, and where the other San Jose residents was working. The role playing is also a reminder of the difficult parts of railroading - the times you're stuck at the top of Tehachapi Pass at the San Diego Model Railroad Museum,  and can't get permission from the dispatcher to leave the siding, or wondering what a switch job would have been like in the rain or snow. It also determines whether we just re-rail those cars that fell in the canyon, or if the dispatcher immediately shuts down the railroad and sends the Big Hook to fix the derailment.

A war-gaming style doesn’t work for us; Joe can’t be a level 5 hostler; if you run over your switchman, that doesn't mean you have a half-effective switchman. But we can try to name ourselves by adjectives, just like in Fate Core. A particular tower man might be “crotchety” and "slow". A yardmaster might be “helpful”. An engineer may be “selfish” and try to tie up his train ahead of others; another engineer may be “know-it-all” and may push the schedule and safety to get to the next siding. A brakeman might be “sleepless” after ten days working without a break. The jobs might have Fate-style aspects, too. A switch job on the edge of the layout might be slow-speed: “don’t sweat it too much”, while a switchman working in the yard might want to feel as if he’s “micromanaged”. Chuck Hitchcock’s Argentine Industrial District Railway sets adjectives like this for certain jobs, with the AT&SF tower man encouraged to favor his own trains and ruin the plans for the crossing railroaders.

But just like the real railroad jobs, some of the role-playing on the layout comes from our own experience. If I operate on Rick Fortin's layout, I know there's experienced crews who know what they're doing, and newbies who make lots of mistakes, and I’m likely to plan for that behavior when I switch the yard. Some of that role-playing falls back on indivdual personality; there's going to be crochety members of the operating session, and mellow coworkers.  If Sam’s the yard master at Keyser on David Parks’ layout, then the yard’s going to be run strictly by the book. If Falkenburg is an engineer, he'll be no-nonsense. If Seth's running the yard, we'll be working double-speed, but he’ll be teaching the newbies out the whole time.

So we're kinda not role-playing - we're just running trains and letting some of our own personality bleed out. That’s not surprising; I suspect the folks who tend to play thieves in D&D probably tend towards the clever and sneaky personality, and the folks playing a paladin probably have a strong sense (or secret inclination) to make sure Things Are Done Correctly And Properly.  We'll role-play a bit outside our normal roles, but most of us probably tend towards acting in a way that has some parallel with our real self.

But model railroading is still role-playing; we need to describe a setting and provide some hints. Our operators need to know whether the rulebook is “more like guidelines” on this layout, or if breaking a rule gets you banished. Our operators need hints about the job and the role, both so they know if it’s a character they want to play, and so they know how to behave towards the others in the session. We can have a bit of randomness to make the system heroic. Perhaps some maintenance work shuts down an important stretch of track, and we all need to pull together to make it through the day. Maybe we should imagine that it’s a winter day, and getting the trains over the hill is a bit of heroism.

Sometimes we just play up the drama. I often describe my own Vasona Branch model railroad as a "high speed, thrill ride switching layout", for I personally like challenging switching puzzles, and I want to invite operators who are interested both in the prototype and in the switching challenges. Like Fate, most of my operators are "proactive, competent, and pragmatic", and if they're not saving the world with their switching, at least they're removing a bit of chaos from the tracks next to the cannery. The real crews, with thirty years of experience switching these same tracks, were probably just as adept at dispelling the chaos.

If I want to inspire my operators with a bit of drama, I can be blunt in my introduction to the layout:

"It's June 15, 1932; apricots are ripe, and everyone's running full-out to can the crop. The canneries have been running double shifts since April on different crops, and you all have been working with hardly a break since then. You've got all the shifts you would want; you don't dare try to take time off, and you've had enough practice so you're confident and working together as a team.

It's six in the morning; the canneries start up in two hours. You need to get the boxcars in position so all those guys on the dock can load the cars up. Go show those guys on the loading docks how railroaders get things done.

But not all my operators are like that; some of my visiting operators, either by choice or by a random roll of the invite list, can be sedate, challenged by puzzles, or are new model railroaders getting thrown into the deep end of the San Jose extra board switching pool. Sometimes, those folks play the role of the new hire on the railroad, destined in his or her first shift to decide whether railroading is the right profession, or if he's going back to the farm where they won't need to distinguish between thirty boxcars in various shades of brown. Some folks might play the character of the old hand who needs some help in the role, which might frustrate the other folks on his train, or might remind folks of how the railroaders protected their own. Hopefully, no one's playing the rest of Ed Gibson's crew on that infamous trip on the Hayward Turn. Sometimes the operator having a hard time on the layout reminds us of crews the real railroad. Sometimes, we hope they'll fall asleep under the layout. Sometimes we'll just want to scream - just like on the real railroad.

To help our operators play the correct role on the railroad, we need to give them hints. We can suggest the tone of the operating session in our introduction and in how we explain our layout, the way the game master does. Just like Fate Core, we can use adjectives to give our operators hints about their roles or their characters. We can also let each operator's personality reflect into the game, either by letting the operators be themselves, or carefully inviting the folks who match the tone for our layout. No matter which way we provide those role-playing hints, our operators will end up making the operating session awesome, and as entertaining as possible... even if they're not a level 5 hostler.

Interested in other story-style role playing games? Check out Tabletop's video of Dread, where characters need to pull a block from an unstable Jinga block stack to avoid bad things happening, or Fiasco's story-telling based on 1970's dance clubs. And if you'd prefer that +16 vorpal sword, check out the card game Munchkin.