Flat Cat!
A #2DAutomata Project
Check out the Flat Cat two‑dimensional automaton!
Slide the tab from side to side and the integrated rack‑and‑pinion mechanism brings this happy little fellow to life.
I’ve been toying with the idea of creating simple slot‑together automata for a while. I wanted to design fun, moving models that could be popped out of sheets of 1400‑micron card and quickly assembled into a lively little character.
There were a couple of details that put the idea on hold. The first was the cutting of the parts. As you’ll know, I like to share my projects online so other people can make them too. For example, if you’re a premium subscriber to this newsletter, you can scroll to the end of the page to download the Flat Cat parts and instructions as a PDF.
I was worried that cutting gear teeth from thick card would be too fiddly. A laser cutter would certainly do the job, but not everyone has access to one. Eventually, during one of the many times I found myself thinking about these models, I decided that instead of wondering whether corrugated card could handle gear teeth, I should simply give it a go. Turns out, no problem at all!
My second challenge was figuring out how to join the parts together. Everything lives in this sort of “two‑and‑a‑half‑dimensional” space, but I still needed a reliable way to attach a front and back cover or align gear pieces. My original plan was to create little dowel pins from the card itself. They worked, but they were fiddly to make accurately and not especially strong.
Then, while I was working on some linkage models, like the seagull from the previous project, it suddenly occurred to me that I could use split pins (or brads, as they’re called in the US). It should have been obvious, but in that way ideas sometimes get boxed into separate compartments, I’d completely overlooked it. When it finally clicked, it felt like one of those delightfully simple revelations.
After a quick visit to eBay, I picked up a selection of split pins in different sizes and colours. I was particularly taken with the bronze ones, so that’s what I’ve used for the Flat Cat project.
I spent a relaxed evening with my sketchbook and pens, roughing out the initial idea for the cat project, along with a possible future design featuring a very contented crab. Both concepts used split pins to hold everything together. With the sketches in place, it was time to try the real thing.
I used Matthias Wandel’s Wood Gears program to create a 22‑tooth gear with 12 mm teeth, exported it as a PDF, then dropped it into Affinity where I added the arms and hands. I did the same for the rack gear, which was also designed in Wood Gears.
I printed the various pieces onto ordinary printer paper, glued them onto card, and then very carefully cut them out.
Final stage of the proof of concept: pin everything together with the gears meshed and the split pin opened out. I gave the rack a gentle pull and the happy little chap sprang to life.
You can see the original version, sans colour, over on my Instagram. You are following me… right?!
I’ve now created a full‑colour version of the Flat Cat project for you to download and make. It comes as a PDF: simply print the parts sheets, stick them onto thin corrugated card, then cut them out and assemble them following the included instructions. It’s a satisfyingly hands‑on process, scissors, a sharp knife, and a small sense of adventure recommended.
You can find it on my website, or, if you’re a premium subscriber to this newsletter, you’ll find the download waiting for you at the foot of the page.
If you sign up for an annual premium membership do let me know and I will be happy to give you full access to all the hundreds of projects at www.robives.com
Thanks so much for following along with this little cardboard adventure. I’ve had a huge amount of fun developing the Flat Cat, and I hope you enjoy making your own just as much. There’s something wonderfully satisfying about turning a few sheets of card, a handful of split pins, and a bit of careful cutting into a character with real personality.
If you do make one, I’d absolutely love to see it, feel free to tag me on Instagram or send a picture my way. Seeing your creations genuinely makes my day.
And as always, thank you for being here, whether you’re a long‑time premium subscriber or just dipping a toe into the world of automata. More projects (including a certain contented crab) are already scribbled in the sketchbook, so stay tuned.
Until next time, happy making!