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I love that feeling when a project finally satisfies some itch I’ve had for years.
I’ve talked about 3d printing a lot on this blog over the years. I’d been an early adopter of using 3d printing in model railroading. Around 2009, I bought one of the early FDM (“squirt out strand of plastic”) printers, the “Makerbot Cupcake”, named for the fact that it could print an object the size of a cupcake. I loved the sense of being able to sketch a design, then turn it into a real object, but found the resulting objects were coarse - good enough for say a coat-hook or a pocket for holding a DCC throttle, but less good for scale parts.
In 2014, a company called Form Labs started selling a stereolithography-based printer. Their printer used a laser to harden a layer of photosensitive resin in a glass-bottom tank. The printer would then lift up the partially-completed piece above the tank bottom and repeat by curing another layer of resin, slowly pulling the completed part out of the resin-filled tank. Other companies had been selling printers with a similar mechanism for commercial purposes in the past, but all were much too pricey for the typical hobbyist. Formlabs appeared just as the original patents on stereolithography were expiring, allowing them to make a similar printer at prices a regular person might be able to afford.
The Form One printer was amazing; it could produce models that were close to injection-molded quality. I found it great for making detail parts, and even managed to print some HO railroad cars - flat cars, the Hart gondolas, the Harriman passenger cars, and a bunch of other stuff. The Form One printer was truly magical; I loved being able to think of a project, and suddenly have dozens or hundreds of a part. It wasn’t the fastest; most of the freight cars took several hours to create, and even detail parts could take an hour or two.
The Form One was also really cute. A little bigger than one of the original Macintoshes, it just looked really cool with its retro orange plexiglass box keeping UV out of the resin tank and curved aluminum case looking a bit more like a 1970’s Braun kitchen appliance than a 3d printer. The folks designing it also had done a beautiful job with industrial design - easy to open and pull out the build platform, easy to send the model from the computer to the printer, and a single button for start and pause.
Beyond my personal project, the Form One also seemed like a great way to share the freight cars that otherwise weren’t available commercially. For a while, I was selling the Hart gondolas, and managed to sell a bit less than a hundred of them, with occasional folks still asking about getting a model. Manufacturing my own model railroad items was an eye-opening project; I loved making these real, but I got some hard lessons on fixed costs for a new product (pilot model, boxes) and challenges for quality when I was making one or two freight cars a day. The technology also had its temperamental moments. The Form One could have print problems because of dust in the optics or resin sticking to the tank bottom. Having only a single printer also made it hard to diagnose problems - I couldn’t just test on a different printer to narrow down causes. A couple hiccups hit just as I was trying to sell a second model, resulting in a bunch of freight car bodies that were too rough to sell where I couldn’t diagnose the cause of the problem.
Ever since then in 2017, I’ve occasionally gone back to 3d printing, but various life issues - work pressures, elder care, printer misbehaving - kept me from making much progress with it. I’ve occasionally hauled the printer out and run some test prints on it, but the effort needed to adjust it and getting it working reliably was too much.
Back to 3d Printing
Form One and Anycubic Photon sitting next to each other.
Meanwhile, another set of companies have been making FDM printers in the intervening ten years. Two Chinese companies - Anycubic and Elegoo - have been selling cheaper printers. They’ve been experimenting with different ways to harden the resin (LCD screens rather than lasers), different sizes, different methods for getting the resin to detach from the tank. I’ve heard stories from friends trying these printers, generally with decent results. "When life calms down," I kept telling myself, "I really need to to check these out."
Luckily, life’s calmed down on several fronts in recent months, and I’ve got more free time. With the threat of tariffs raising prices, it seemed like a good time to try one of these printers out. Because the Form One had always been a bit too small to print 40 foot cars in easy ways, I decided to go with one of the larger printers - the Anycubic Photon Mono M7.
Verdict? Wow.
A dozen Battleship gondolas, all printed in a couple days.
Battleship gondolas in detail. These are at least as good as the Form One prints when that printer was at its best.
It's been pretty magical and fun. I started off printing various simple parts I'd designed in the past, but quickly threw something challenging at it: one of the Battleship gondolas. I'd done the model for these early steel freight cars back in 2017, but never could get them to print reliably as the Form One aged - print quality was poor, and at best I could print a single car overnight. (To be precise, the Battleships took 5 hours on the Form One.) With the new Anycubic Photon, I found I could print three cars at a time, and they'd complete an a bit more than an hour. This is what I’d intended 3d printing to be like - being able to print fast enough to build up a stock to sell. Within a couple days, I had a dozen car bodies ready. I found the quality of the cars as good or better than the Form One at its best, and the speed and yield was good enough so that I could do mass production if I really wanted to.
Anycubic vs. Form One
So far I've been really happy with the Anycubic Photon, but it's been hard not to compare it to the Form One. The speed, print quality, and volume printed are all great. One really nice feature of the Anycubic Photon is that I can use the whole print surface. On the Form One, each layer of the part was detached from the tank bottom by hinging the tank and swinging it down and away. This was a decent method, but meant that peeling forces on the part closer to the hinge were lower than the forces of the tank pulling away from the far side of the tank. As a result, particularly big or delicate models really needed to print close to the hinge to avoid portions of the part breaking off and sticking to the tank. I found myself only ever using about half the available print surface to avoid failed prints. On the Anycubic Photon, a springy clear sheet is used for the tank bottom; to detach the part, the build platform raises vertically, causing the sheet to stretch up and peel off. This different peeling process means I'm able to print larger objects and print across the whole tank without problems.
There's also been some drawbacks to the Anycubic Photon. The photosensitive resins used by both printers aren't particularly nice chemicals, but the resin provided by Formlabs had a lot less odor. I'd been able to operate the printer inside the house - particularly handy when the printer needed a clean, warm, dust-free space to avoid messing up the optics for the laser. Anycubic's resins have a much more overpowering odor, probably not helped by the printer heating the resin up to 35'C for better curing. Though the odor isn't a good proxy for safe vs. not safe, the stronger fumes definitely make me cautious about potentially dangerous fumes. It definitely doesn't feel safe to be in the same room as the printer when it's operating. FormLabs argues that some vendors' resins contain more toxic base chemicals which might explain the differences. Ventilation systems are available to route the fumes outside; I'm looking forward to trying one of these. The Anycubic printer's LED screen used for curing also is less affected by dust, so it may be reasonable to just banish the printer to the garage.
I've also found it fun to spot the differences in industrial design. The Form One was much better for retrieving parts. The hinged lid could easily be opened and closed one-handed - helpful when the other hand was trying to pull out a build platform with a just-made print still dripping resin. The Anycubic Photon has an acrylic cover that fits over the tank and build platform, but removing the cover requires two hands and a place to put the shell temporarily. The Photon's build platform also gets fully submurged during operation, causing resin to pool on top of the buld platform. This resin spills or drips whenever the build platform and part are removed from the printer. The Form One's build platform was never fully submurged, so it didn't collect resin in the same way.
For cleanup, my original Form One relied on a manual approach - a clean and dirty tank of isopropyl alcohol, and a little basket to agitate the printed parts in each tank to clean off resin. The Anycubic Photon (like later Form Ones) has a separate cleaning tank device that automates the process: all I need to do is put the printed parts in the tank and press a button for a few minutes of agitation in ispropyl alcohol. It's really nice not to have to spend several minutes manually agitating the part to get the extra resin off.
What about the future?
I'm glad I've bought the Anycubic Photon, and I'm having fun getting back into 3d printing. For now, I'm mostly seeing what I can do with the 3d models I'd previously printed on the Form One, and thinking about what projects I need most urgently for the Vasona Branch layout. My two immediate projects are some simple Ford Model A cars for a cannery parking lot scene, and lots of cannery women figures for some of the nearby streets.
The Anycubic Photon also has me thinking about whether to sell 3d printed models again. I had a lot of fun selling the Hart gondolas - figuring out how to manufacture, box, and sell them. I also like sharing these models: helping to tell the story about how freight cars evolved, helping early 20th century modelers have more realistic freight cars to put on their layout, and encouraging others to try mass-producing their own freight cars. I haven't decided whether I'll go back to manufacturing. For now, I'm enjoying not having the pressure of making and selling the cars. But with the Anycubic Photon, I can see that I could mass-produce freight cars again if I wanted.
