An Astronomical Mechanical Clock, In More Ways Than One

Astronomical clock

If the workings of a mechanical timepiece give you a thrill, prepare to be blown away by this over-the-top astronomical clock.

The horological masterpiece, which was designed by [Mark Frank] as his “dream clock”, is a riot of brass, bronze, and steel — 1,200 pounds (544 kg) of it, in fact, at least in the raw materials pile. Work on the timepiece began in 2006, with a full-scale mockup executed in wood by Buchannan of Chelmsford, the Australian fabricator that [Mark] commissioned to make his design a reality. We have a hard time explaining the design, which has just about every horological trick incorporated into it.

[Mark] describes the clock as “a four train, quarter striking movement with the fourth train driving the astronomical systems,” which sounds far simpler than the finished product is. It includes 52 “complications,” including a 400-year perpetual calendar, tide clock, solar and lunar eclipse prediction, a planisphere to show the constellations, and even a thermometer. And, as if those weren’t enough, the clock sports both a tellurion to keep track of the Sun-Earth-Moon system and a full orrery out to the orbit of Saturn, including all the major moons. The video below shows the only recently finished masterpiece in operation.

[Mark]’s dream clock has been under construction for the better part of two decades, and we applaud not just his design but his patience. The skeletonized construction reminds us of the Clickspring clock from a few years back; now seems like a great time to go back and binge-watch that whole series again.

Thanks to [J. Peterson] for the tip.

29 thoughts on “An Astronomical Mechanical Clock, In More Ways Than One

      1. I have read some of the build log linked to below, it is based on a Harrison H1, the standard of this work makes everything I have ever made look absolute rubbish, although I see brass sheet being cut with a wire eroder, the brass wire feeds extremely fast compared to the one I worked on many years ago, maybe so that it can be reused, whereas single use for high precision.

    1. Nice to see someone else definitely saw the similarities to Harrison’s marine clocks.

      I have heard of Buchannan’s work from a professional friend who’s a full time clockmaker that actually makes clocks from scratch himself. He taught me traditional gear cutting, and this guy’s work was something he was in awe of- when he himself is very skilled.

      I trained in school for watchmaking, and have made parts for clocks and watches, but I work as a prototype machinist now. This impresses the heck out of me. It will take some time to look over and see everything it has going on.

  1. Astonishing! A true horological masterpiece – Bravo!
    Also see timekeepers like this built in the mid to late 1700’s using hand tools by candlelight; i.e. John Harrison’s Timekeepers H1, H2, H3 and H4

  2. Wonderful!
    And I only thought of building an Orrey sometimes.

    I was always fascinated by the planetarium clock in the “Bayerisches Nationalmuseum” in Munich. Sadly the clock is not working there – and no good picture of it in the net.

    1. Are there any on instagram?

      There is at least one orrery maker on instagram with an excellent account.

      If there arent pictures of this, upload some if you have them, there are definitely other people out there that would like to see what you find cool and I am one of them

  3. Spring powered?
    How many jewels?
    A real pain if it ever needs to be reset? (Synchronizing the various movements!)

    And importantly,
    Don’t let a 3 year old near it!
    B^)

    1. Ha ha! When my dad was a kid his big brother returned from the service with a beautiful German mechanical clock. One day when he was alone he took it apart, then panicked when he couldn’t put it back together, so he buried it in the back yard. Everyone in the family knew that he was behind the great disappearing clock caper, but no-one said a word — I guess he must have looked really mortified.

    1. Yes! Jens Olson’s astronomical clock is a masterpiece. Otto Mortensen did a book on it called Jens Olson’s Clock- it’s kind of rare but I have a copy. If you’re really interested in it I’d highly recommend you see if you can find a copy for loan from your library system it’s a really amazing book, covers all the functions of the clock and it is extremely complex.

      For others who like astronomical clocks- my favorite book on them is definitely Geared To The Stars by Henry C. King. It’s a rare book as well but I think there is a copy of it available online to read for free. Better library systems usually have a copy of it for loan. If you really want to see how these things progressed and how the gearing was done there is no better book to look for.

      It’s unfortunate but because it’s such a niche subject a lot of the information on these things is found in rare books. If you really like this stuff- consider joining the AWCI (American Watchmakers Clockmakers Institute). They have an enormous library and loan system for members for a lot of these rare books that are almost impossible to find. They even teach classes on gear cutting and other such topics. I’ve been a member for over a decade, it’s a great organization

  4. The results are lovely and the craftsmanship and artistry amazing. But there are some aspects of this device that trigger my suspicion sensors, at least slightly.

    What is the function of the two oscillating arms? Their period is about 1 second, but they certainly cannot be pendulums, and they’re too slow to store a useful quantity of kinetic energy.

    And that planetary-geared fan (aka ‘fly’) can’t be serving any speed-regulation function that would be useful in an orrery or anywhere else save the chime/strike trains.

    The “antennae” that wave behind the escape wheel are similarly mysterious.

    The machine may well be a cleverly designed astronomical clock, and please accept my apologies if it is. But the imposing brass device shown in the video looks very much like an art project instead of a horological device.

    1. I am the person who commissioned this clock. If you went through the the website that describes the build of this machine your questions would be answered. But to be brief, the two oscillating arms are compound pendulums. Just as John Harrison used in his H1 marine chronometer in 1735. His was a one second and mine is a two second, I think the longer period is more hypnotic. But it is a real pendulum controlling the time nonetheless.

      The two fly governors on the towers are used to mediate the recoil of the two remontoire that power the twin Harrison escapement wheels. They are not for decoration and have nothing to do with the orrery. You can go to my website here to read up on remontoire: https://www.my-time-machines.net/remontoire.htm.

      I am not sure what you are referring to as ‘antennae’ these may be the escapement pallets that are whimsically made to resemble pecking birds on the escape wheels. but again, as with everything on this machine they serve an actual purpose. While we went to great lengths to add complication and visual treats – an overload to the gear head’s addiction – nothing is superfluous.

      You are right that it is a work of art, but it is absolutely a serious horological device – everything is real and works and has a purpose. Please do contact me on the website and I will be happy to have you come by for a visit! Or in a few years after donation, it will be at the Adler Planetarium.

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