When mine stopped running a couple of years ago, I was able to find a retired clockmaker with a pretty good knowledge of these. He tested the bellows and said there were no problems there. He recommended a manual winding of the mainspring for $75 and said I need to leave it outside occasionally. That will cause the bellows to contract more than it normally would indoors.
This is death to an Atmos. It works best in a drafty old European castle.
gatorcpa
I wonder if anybody following this thread has an Atmos owner's manual? If so, does it actually say that temperature change contributes to the winding of these clocks? Considering the brutally strong steel coil spring that the bellows has to expand against when atmospheric pressure falls, I would be very surprised if one or two degrees variation in temperature would contribute to winding.
Temperature variations are its source of power. Its balance will oscillate as long as the sun shines. Rises in temperature dilate the gaseous mixture trapped in the expansion chamber which then compresses the winding spring. In the event of a fall in temperature, the reverse occurs. The gas contracts and the spring relaxes. This imperceptible back-and-forth motion is sufficient to wind the Atmos clock.
I wonder if anybody following this thread has an Atmos owner's manual? If so, does it actually say that temperature change contributes to the winding of these clocks? Considering the brutally strong steel coil spring that the bellows has to expand against when atmospheric pressure falls, I would be very surprised if one or two degrees variation in temperature would contribute to winding.
Well, this all is news to me. I have long been under the impression that it was change in atmospheric pressure that wound these.
I have long been under the impression that it was change in atmospheric pressure that wound these.
Even then scientists knew how dangerous mercury was in the quantities needed to run an Atmos.
That was true of the original design, which ran off the movements of mercury (like a barometer).
With the discovery of how toxic mercury really was (and they needed a lot of it to run the Atmos), JLC and Reutter designed a different winding system based on boiling of ethyl chloride at roughly room temperature.
gatorcpa
Im not normally into clocks but the JLC Atmos is something rather unique and special being what it is. There are numerous cheap (sub $1000) two hand variants on eBay that all seem serviceable but I'm wondering a few things:
Are these cool enough to be worth owning?
Very cool. Closest you'll get to a perpetual machine, and when you tell people it never needs winding, no battery..that's cool too.
They MUST be placed on a steady solid surface with no movement whatsoever. That's why they even sold a wall shelf years ago. Mount it to a wall to avoid movement. I believe they were designed as a mantle clock, a mantle usually being the most secure placement in the home, as long as you don't use the fireplace underneath. They are incredibly sensitive to their environment. 1W of energy could power 30million Atmos clocks(yes million). The balance twists on a long and very very fine wire (hangs like a pendulum but twists instead of swinging). They are very easy to stop, and I believe that is the most common issue.
A full winding of the mainspring will run the clock for just over two years without rewinding.
The pendulum only consumes 15% of the mainspring energy, with the gear train and escapement consuming the rest.
It only takes 1 degrees of temp variation to run the clock for two days. That's way within normal variation in a house from day to night. I fact it only takes 0.25deg F to advance the mainspring by one click.
Re temp vs pressure on winding, temp variation is 90% of the winding, and pressure changes contribute the remaining 10%. Pressure changes are quite small day to day, and only serve to "shift the curve" on how temp changes contribute. So temp and pressure work together, with Temp being the major factor, and Pressure being the minor factor.
Are they reasonably accurate enough long term?
A well cared for and adjusted Atmos will run seconds/month. Yes, seconds.
Are they a big risk of damage in shipping?
Yes, because you ship with the glass case as well to protect the movement. There is a lever on the bottom of case to lock the balance in place for movement and shipping.They must be double boxed. The JLC box is the best box to use but I don't have one so I used the advice of the watchmaker I'm sending it to. Its bubble wrapped around the sides, then around the top and bottom, then in a sturdy box with peanuts packing to fill in gaps, and that box then goes into a larger box filled with peanut packing on all sides. Its a big box. The greatest risk in its whole life will be in general movement and shipping.
Are they expensive to maintain or difficult to find a clockmaker to work on them?
It's a talent for sure and few have it, plus it CAN be expensive. JLC will only supply certain watchmakers, so there are very few qualified in the first place, and parts are expensive. Generally I have been told its about every ten years for a service, in a clean home. As there is virtually no lubrication and the case is open to atmosphere, mere dust can slow the movement.
There are alot of crap Atmos out there. Like any fine timepiece, history matters. That's why it has taken me almost three years to find a good one. Even if it looks perfect, assume it will need a cleaning just to run. Its not a like a watch where they can be in poor condition but still run. An Atmos has to be in virtually perfect state to run.This is the one I found(below), and actually found it locally at an estate sale for $450. Virtually perfect condition, 1962 model square face with matching gold wall shelf (a $1000 accessory back in the day). The shelf alone is worth ~$250 (and currently for sale as I don't need it)so I basically have $200 in the clock. Well worth the additional cost to clean. When I got it home it took several days to adjust to the new environment and It still only runs a couple hours and stops, classic need for cleaning. The cleaning will probably be $400 plus $100 shipping for both ways, so $500 total. All told I expect the clock to be in for $700 total when I'm done, assuming no parts replacement. For comparison, they are ~$7000 new.
Do they turn off watchmakers as much as normal clocks do?
99% of watchmakers won't touch one because of the talent and knowledge required, and that they can't get parts.
If your interested I'll post some good websites and information on Atmos, or just PM me. I even have a Clemson U research paper on the operation of the Atmos. Fascinating.
Hi all
Take a look a this site.. .they have some really uncommon examples...
http://www.atmosadam.com/atmos.html
its not the easiest site to navigate but some really killer stuff!!
Bill
I have to disagree.
Hey Bill, what are disagreeing to? I reread you text twice and can't figure out what... 😵💫
