Is a "cheap" time-only JLC Atmos clock worth owning?

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?

Are they reasonably accurate enough long term?

Are they a big risk of damage in shipping?

Are they expensive to maintain or difficult to find a clockmaker to work on them?

Do they turn off watchmakers as much as normal clicks do (Archer is one among many who avoids them in part due to the hazards involved but I'm wondering if the mainsprings are less meat mulching than normal clocks)?

They do seem like an incredible buy due to being so unique, and a JLC and not taking up wrist space.

Its a more generalised question applying to a category of Atmos clocks, along these lines:

http://www.ebay.com.au/itm/Atmos-Cl...770411?hash=item3d2a111feb:g:oZUAAOSwHMJYEdpQ

Yes they have a lever on the bottom which locks the whole mechanism in place for transporting. They are supposed to be very sensitive to movement so must always be well packed when sending in the post.

The older models provide incredible value for what you get, considering the new ones in the JLC boutiques look practically the same.

If looking at getting one I would definitely go for one which has been recently serviced as I understand that repairs on these cost an arm or maybe leg. There are a few eBay sellers which specialise in Atmos clocks.

I bought one of these for under $500 back in 2005. I've had pretty good luck with it, but still have had some issues (see below).

So here goes:

1. They are extremely accurate when leveled and properly adjusted. I generally adjust mine only on when the time changes. Rarely off more than a couple of minutes in 6 months time. Make sure the clock has the original bubble level installed. Some of the older ones have lost the liquid inside.

2. You want one with the original fitted box. The later ones with the fitted Styrofoam lining are best for shipping. It is not a easy thing to ship without damage, particularly if its going all the way to Australia. Mine came with the Styrofoam, but without the outer box. The seller packed a larger box with packing peanuts. Sent it UPS Ground for safety. No problems.

3. A full cleaning is rather expensive. Most clockmakers can't or won't work on them as parts may be difficult to find. Although lately, I've been seeing a lot of parts for these on eBay. The bellows with the ethyl chloride can develop slow leaks when they get old, which can lead to winding issues. Expect to pay upwards of US$500 for a proper job. Add anywhere from $100 (for a refill) to $500 (for new) if the bellows need refilling.

4. My understanding is that JLC will sell parts to clockmakers whom they've certified. Who they are and where they are located, I really don't know. I think factory service starts at something like $2,000, plus shipping both ways. Ouch! 😲

5. 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. My clock is again starting to slow slightly and the pendulum isn't going around the proper 540 degrees (1.5 turns). Still keeping decent time, so I'm hoping it will last until the winter cold fronts start dropping the temperature around here. Otherwise, I hope the viejo is still around.

Hope this helps,
gatorcpa

Not to get off into the weeds but I've owned 2 of these. Ordered the first as soon as I could. Fell in love with the concept at a new car show in 2005. Production model was very close to the concept which is rare. Ran the first one over 200K miles and gave it to my son. My 2nd is now over 200K miles. Bulletproof. Very reliable. Outward vision is a little quirky. 1 cup holder. 1 power outlet. No carpet. It screamed childhood Tonka Toy so I had to have it. I would buy another but they are no longer in production and the used prices have gone up beyond reason 🙁

Check out this thread on these clocks. Servicing is expensive so get one that has already been serviced. Also, assure that the finish of the metal is in good condition.

Clock has temporarily died. 🙁 Taking it back to clockmaker next week. He said I should be leaving it outside more often than I have been.

Manual winding is easy if you have proper tools (he does).
gatorcpa

It is the variations of temperature that causes the bellows to expand/contract, not pressure. Wikipedia.

The original Atmos clocks were made with mercury. Those ran on changes in pressure. Even then scientists knew how dangerous mercury was in the quantities needed to run an Atmos.

Beginning in the late 1930's this was changed to ethyl chloride, which boils at room temperature. The focus changed to temperature at that point.
gatorcpa

In fact atmospheric pressure variation is minor contributor to winding the clock. I pasted a graph of variations of vapor pressure versus temperature of the gas in the Atmos bellows (ethyl chloride). We see that the slope of that curve is 0.0524, meaning the pressure exerted inside the bellows varies by 5% for each degree of change of temperature. Assuming that a typical household has variation of 3 degrees Celsius within a day then pressure varies by 15%. Atmospheric pressure rarely varies more than 1% within a day, so we see that it has little influence on winding the clock. Here are other links here and here on the workings of the clock.