It was an unseasonably warm Saturday afternoon in Brooklyn, and I was walking my dog when my phone buzzed with a text message from a friend at Rolex, containing only a link to something on Thingiverse (a 3D printing file-sharing site). I opened the link and my jaw dropped; I was looking at a 3D printed tourbillon watch running by itself, built by Christoph Laimer, a Swiss engineer.
This is an actual watch, with a tourbillon, that is almost entirely 3D printed. Think about it: the tourbillon – a 200+ year old invention designed by one of the greatest watchmakers to ever live, which for most of its history has been practically synonymous with hand-craftsmanship and high end watchmaking, has been produced in a working watch with a 3D printer.
You can wind it, set the time, and carry it with you. Sure, it's a bit large (a pocket watch, not a wristwatch, and they'd need to be good sized pockets to boot) not very accurate, and only runs for about 30 minutes – but none of that is what really matters. What matters is that this watch was manufactured using an affordable consumer level 3D printer (an Ultimaker 2). To top it off, Laimer made all of the source files available for free! Sure there have been watch components made in the past, but this is the first (as far as we have been able to determine) entire, working watch that is 3D printed: every gear, escapement component, the case, even the balance spring and mainspring – and we have to emphasize that it's not just a collection of files, it's actually running.
The only non-printed parts are the metal pins used as the axes for the gears, and some screws and washers (aka "vitamins" as non-printed components are called in the 3D printing community).
This is huge news for watchmaking, of course, but was also very big news for me personally. To see why, let's take a step back to the summer of 2014. I had just completed my own attempt at a 3D printed horological project: the Tourbillon 1000%, which is a 3D printed tourbillon with a co-axial escapement. Tourbillon 1000% isn't a complete watch though; it's just the tourbillon mechanism and fourth wheel, and doesn't include any gear train or barrel. It doesn't run by itself; instead it requires a human to provide power to the tourbillon carriage while holding the fourth wheel.
I had big plans to continue work on Tourbillon 1000% and build an entire movement that would run by itself, and I worked on this project like crazy, but ultimately stopped after hitting many apparently unsolvable roadblocks. The last prototype of the not-really-working complete movement for the Tourbillon 1000% now lives on a shelf at HODINKEE.
How did Christoph Laimer overcome the issues that I faced before stopping work? He built his watch by arranging his gears in a vertical stack rather than the usual horizontal arrangement, and also he used a different type of bearing than I did.
A major consideration in any 3D printing project is the relation between the nozzle diameter (X/Y resolution) and bed size (how big a printed part can be, in X/Y/Z). These two variables determine the overall scale at which the project can be printed – for practical purposes in a watchmaking project, they determine how small you can make your watch. Usually, traditional watch movement architecture isn't compatible with ratio between nozzle diameter and bed size found in most 3D printers. (One part in particular causes the most problems - the mainplate). So, instead of using traditional horizontal movement architecture, Laimer instead built upwards, layering parts vertically. Notice that his tourbillon is directly on top of his mainspring barrel. Historically, this makes a lot of sense. If you take a look at early portable timepieces – the first watches – you'll see that they're often nearly as tall as they are wide. There are a lot of reasons for this (including the height of early fusée cones, and the fact that the earliest known escapement – the verge – is inherently thick) but one relevant issue is that machining techniques for those first watches didn't allow for the high precision needed for a flat (Lépine style) movement. In my case, my mistake in designing the Tourbillon 1000% was sticking with conventional, modern movement layout.
In a mechanical watch, we are familiar with seeing pierced jewels being used as bearings. The hard bearing surface allows for a pivot to rotate with a low amount of friction. Laimer used gears with steel pins running all the way through them, on which the gear rotates, rather than the usual arrangement of pivots in jewel bearings. This allows for higher strength and low weight in the movement construction, and for the ability to mount gears co-axially. (Notice the escape wheel and balance share the same axis). My approach was more traditional, using skateboard ball bearings and traditional pivots for the gears. This caused my tourbillon to be much heavier than Laimer's, meaning that more power was needed to keep it moving. That extra power, combined with the inherent weakness of 3D printed parts when compared to traditional brass and steel, was a recipe for disaster. Teeth were literally snapping off wheels!
The 3D Printed Tourbillon Watch is Laimer's second horological 3D printing project. His first was a wall clock, driven by a weight of 1.2kg. I spoke with Laimer to find out more about his development process and plans for the future:
Where did the idea to stack your movement vertically come from?
The design is driven by symmetry - I love the mental link of the sun-gear with the escapement-wheel, and the anchor floating like a planet around the sun. With the co-axial escapement-gear, the tourbillon has a much lower inertia, and the counter-weight needs only to balance the lever and the planet gear. Last but not least it's important for the 3D printing community to keep the non-printable parts as simple as possible.
Are you a watchmaker, or in the watchmaking industry?
I'm not a watchmaker. I studied electrical engineering, with 18 years professional experience in computer science, managing a small team, and developing software for the lifescience industry. At the moment I'm taking a time-out in order to explore interesting things, for which I never had time before.
Is the material all PLA (polylactic acid, a plastic commonly used in 3D printing) except for the case (PETG)?
Yes. Except for the main spring: there I tried 2 versions (in both) PETG and PLA. Both not ideal, but I was still surprised that I could get it running for more than 5 minutes. Maybe the community will continue experimenting with other materials.
What was your inspiration for focusing on horological 3D printing?
When I bought my first 3D printer, I realized, that many people were designing "stupid" decoration pieces. I wanted something useful, and so I started experimenting with custom LEGO-gears for my children. Some iterations later I had designed and printed the gear-train with hollow shafts for the 3 clock-hands, "only" the escapement was missing. That was the moment when I realized, that a clock is THE living creature, which finally made (it make) sense to own a 3D printer.
What are your next steps?
My family explained, that my time-out is over now. Since I very much like designing complex mechanics in 3D, I'm keen to find a new profession. Maybe the published watch can help?! I certainly won't stop constructing things with my 3D printer. I'm wondering, if I would buy a 0.25mm nozzle, if gears with module 0.3 are printable (that is, it might be possible to print smaller gear teeth and thus make a smaller watch -Ed.) . If I'd also replace the plastic main-spring by a real steel spring, it might be possible to print a wearable thing that runs for 12-24 hours. These are only fuzzy thoughts about my next project - certainly, it will be something else (as long as it is challenging and inspiring).
3D printing is often touted as the next frontier for manufacturing, and work like this goes a long way in making that more real. It's interesting to see how very old-fashioned movement architecture is reflected in this work. Sometimes a step forward requires looking through the rear view mirror!
Laimer mentioned that he is working on a small series of his 3D Printed Tourbillon Watch that he will offer for sale, for those that don't own their own 3D printer. Interested? Contact Laimer on Thingiverse (account required).
All photographs and renderings courtesy of Christoph Laimer.
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