Hello all, This is my first post so go easy on me! I recently graduated from college with a mechanical engineering degree. For my senior design project I was tasked with designing and building an all-mechanical clock capable of displaying the time and date (while accounting for leap year) which would only require a rewinding once a year at most. As I'm sure you can guess, the project was a total failure! I was unable to come up with an appropriate design which accounted for a leap year or find any reference to an existing calendar clock that can run as long as I wanted. I am aware there are existing anniversary (400 day) clocks with run about a year by utilizing a torsional pendulum and Atmos clocks which run "automatically" via a gas bellows design. Is anyone here aware of any calendar clock that can run for this long? Is it even possible? I figured the best place to start would be to buy a Seth Thomas or Ithaca Calendar Company clock and attempt to replicate or re-engineer it. I've done a lot of research over the past year and a half or so but haven't had much luck. Considering that I'm now done with school this project isn't a necessity and I tried to just drop it but my dumb brain won't let me forget about it! Any suggestions you guys have would be much appreciated! Thanks!
Grains - Your brain is not dumb. This clock thing catches hold of us, and often never lets go. Your idea of powering an existing calendar clock isn't that far-fetched. You'd need to make a 52 to one gear-up train, probably with a couple gear-pinion reduction sets (e.g. 96-12, 84-12) and powered with a couple hundred pound weight. This could be with industrial gear sets easily available, to carry the substantially greater load, and then transfered to the existing clock via chain-drive. This probably would take a little more thinking, but this is a start. Keep us in the loop. Johnny
Thanks for the encouragement John. This one's got its grips on me. I know it's possible, it is just a matter of how ridiculous it is to accomplish! I've agonized over this for a while but I'll definitely keep you guys updated on my progress. I'll be around with many more questions I'm sure.
Here is a link to a 1 year running clock. Philippe Wurtz Note what he has done: 1. Tungsten drive weight. About 50% greater SG than lead so for the same fall it delivers more energy. 2. DLC coating on pinions to reduce the friction. 3. Escape wheel has minimal inertia so it is easily accelerated from stationary (& that happens 86 400 times every day). 4. All pivots are ball bearing (see description of Sarlat) & here http://www.philippe-wurtz.com/images/press/hj_nov2004_comment.jpg I know of a German 4-year running clock but I can’t find the link. It is a grandfather clock but the case is a bit longer than normal so it has more drop than usual. But that only contributes slightly to the extended run There is, of course, the 10 000 year clock. It uses a ball screw drive. Introduction - 10,000 Year Clock - The Long Now Here is a link to how to make a calendar. Astr 01-15
Wow, thanks so much tok. I've done some preliminary research on potential low-friction material for clocks such as iridium or various carbon fibers but the Wurtz clock proves it out. I'll definitely have to look more into it. Thanks very much.
There's a detailed description of a relatively simple perpetual calendar mechanism in the last chapter (or very near) of Ward Goodrich "The Modern Clock". Johnny w
I was allowed to make drawings from an existing perpetual calendar. May be of help ? Some "regular" screenshots and a rotatable... 3D-PDF. (Functions only with Adobe PDF-reader and adapting the settings for 3D-PDF's; so first download and thereafter view). Hessel
This is a great help! Do you know what calendar this was based off of? It looks as if this particular mechanism is only the calendar portion of the clock.
Grains, This mechanism was made as an exercise-project for a young clockmaker about 35 years ago. So it never was part of a clock. But …. of course the central axis can adapted to a clock mechanism. If I remember well it was published in an 18 century book..., but I don't know the real origin. Hessel
Hessel, I appreciate you sharing the design with me. I'm currently trying to work out exactly how to design an escapement. There are many variations.
