Classic watches, watchmaking, antique tools, history, vintage ephemera and more!
Learn about mechanical timepieces and how they work, the history of the American watch industry and especially all about the Elgin National Watch Company! Check back for new content daily.
Although this is technically a blog, the content is not generally in a time-based sequence. You can find interesting items throughout. Down the page some is an alphabetical word cloud of keywords used here. A great way to dig in is to look through those topics and click anything you find interesting. You'll see all the relevant content.
Here are a few of my favorites!
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The secondary serial number stamps have an inverted V like symbol.
The two types of movements exist so that 12:00 will face up when placed in the corresponding case. A hunter movement in an open-face case is usually called a side-winder because the stem will fall at 3:00. See some examples here.
This watch has an open-face movement in a hunter case. Or is it? Careful observers will notice that this is a key-wind, key-set Elgin. The crown does not even turn. This movement has no place for a stem from the case to go in. The orientation of the movement does not matter at all.
It's not the movement that is open-face style. It's just the dial that is.
The orientation of the movement in the case is dictated by a pin in the edge of the movement that goes into a hole in the inside edge of the case rim. The location of that hole orients the movement. And some cases of this type indeed have a hole in two locations, 90 degrees apart, for just this situation.
See the whole album for this watch here.
Find more content about vintage watches here.
See the whole album for this watch here.
Find more content about vintage watches here.
HandsThe hands on a mechanical watch are geared together. They can not, if everything is functioning correctly, move independently. Their movement relative to each other is mechanically dictated by gear ratios. For example, the minute hand must advance one minute each time the seconds hand completes one trip around. Likewise the hour hand must advance one minute each time then minute hand completes one trip around the dial. It can not be otherwise as the hands are mechanically joined by gears.
One can see these jumps in the movement of the seconds hand on a mechanical watch. The other hands are also jumping, all at the same instant.
EscapementMechanical timekeeping is possible because of an escapement. The escapement "escapes" power into the gear train many times a second. At each beat of the escapement, the gears turn. Then they go still again in between. The escapement controls the frequency of the hands advancing, and thus the accuracy of the watch over time.
What is time keeping?
Mainsprings impart more power when first wound than when almost run down. So the rate of a watch wound in the morning varies as the day passes. Watches may have some means of compensating for this. Most older ones do not.
Gravity effects the hairspring. The hairspring and the balance wheel dictate the frequency of the escapement, and so alter the reading of time on the hands. A wristwatch is in many different orientations as it is worn, so the rate varies over the day, moment to moment. Again, some watches have the means to reduce this variation.
These are just two examples. There are more many factors that also alter the watch escapement from moment to moment under normal operating conditions, on a watch that is functioning correctly. Because these issues exist, watchmakers of old did not even bother to measure a watches rate moment to moment. They were only interested in a watch that read good time after running for some period without being reset (a day, or several days). Sometimes during the run interval the rate may gain, and sometimes lose. Watch "adjustment" is setting up everything so that plus and minus errors (the ones we can do nothing about) cancel each other out over time.
In these cases, there are several adjustments that can be made. One can adjust the mass of the balance wheel. The balance screws provide this mass. They can be replaced, in opposite pairs, with lighter or heavier screws.
This is time consuming work. Once the screws are disturbed, the rate will usually be way off, out of the ballpark. Pulling it back in takes a lot of basically trial and error.
The RegulatorAll of the above applies to watches that have been correctly serviced and repaired and are functioning correctly. Watch designers selected mainspring strength, gears, hairspring strength and balance mass to result in a watch that would be in the ballpark of the correct time after the passage of an interval (say 24 hours). Was a watch, assembled at the factory, ready to go and accurate? No. Manufacturing was not that good. It was close though. So what did they consider "in the ballpark"?
We actually have a pretty good idea. Mechanical watches feature a regulator that can be adjusted by a watchmaker, or the end-user if they like, to effectively lengthen or shorten the installed hairspring, and thus alter the frequency of the beat, and thus the rate of the watch. On vintage pocketwatches, the range of the regulator is about +/- 5 minutes per 24 hours (this does vary from design to design, it can be as much as 10 minutes) over the end to end sweep of its setting.
So, we know that watch designers knew that between variation in manufacturing precision, and variation in real world conditions, an error of +/- 5 minutes was to be expected.
A Proposition...Within the range of error provided for by the regulator, a fully serviced watch is functioning correctly.
The people that designed the watch did their job as well as they could, with the tools and technologies of their time, and within their business requirements. If they could be assured that each watch would leave the factory more accurate than they did, they would have reduced the range available on the regulator. Or perhaps left the regulator off altogether. In short, the range of the regulator represents the expected range of error in a perfectly working watch.
Whether a watch was an economy 7 jewel model, or a high end 23 jewel watch that originally cost 15 times as much, after 100 years they are all individuals. It doesn't matter what sort of watch it is if it's been through two loads of laundry, a fire, and stored in a damp and dirty junk drawer in the garage with the oily rags for 30 years. Watches are not magical. They are constructed (mostly) of machined pieces of relatively soft metal. Countless damages can happen to these parts over the decades that can not be undone.
What's more, a 100 year old watch has likely been serviced and repaired dozens of times, with varying levels of appropriateness. It is extremely common to see parts in a watch that have been replaced with the best thing available at the time - an incorrect or handmade part, and the rest of the watch permanently altered to make an incorrect part work.
In short, it doesn't matter what the watch once was. It matters what has happened to it since it left the factory.
AdjustmentNow we come to the heart of the matter. Just how accurate should we make an antique watch? I'll make several points about this.
1) It doesn't matter.
What's important is that an antique is in good condition, functioning correctly, rust-free, correctly lubricated, stored in a clean, dry manner, and preserved for future generations. Even setting aside family heirlooms, how well a watch keeps time (once it is functioning correctly), among serious collectors, is not even a secondary concern. A watch that keeps time to +/- 30 seconds a day is not automatically "better" that a different instance of the same watch that runs +/- 1 minute a day, In fact, the opposite may well be true as so many other factors are more important.
If someone wants to pay me for the 40 hours (or more) that it might take to bring a hypothetical watch from +/- 10 seconds a day to +/- 6 seconds a day, in multiple positions, reliably, let me know. They did that sort of thing at the factory, but on dozens of brand new, mint watches, all at the same time.
Why worry about time keeping at all? With basic effort, and service by appropriate procedures, many (no, not all) watches fall with a minute or two of error fresh off the bench before I even touch the regulator. How much time and effort should be devoted to fine tuning?
Well, before answering, keep in mind that the watch doesn't "care", at all. Once it it operating correctly, there is no difference at all, for the watch, if the error is two minutes or 10 seconds a day. So the only reasons to do adjustment, are for time keeping, or for fun. As for the former, if you want to know what time it is accurately, and that is important, get a cheap quartz watch or use your mobile phone. These are a 1000 times more accurate than any mechanical watch will ever be, new or old.
So how much effort? I try to strike a reasonable balance. Almost all get to less than 10 seconds a day of error in at least dial up position, and many less than +/- 5 seconds. I consider that excellent. These watches come from a time when it was not unusual for people to be walking around with watches that read +/- 10 minutes a day.
I spend more effort reducing the beat error than the rate though, since beat error is actually a fault causing inefficiency, regardless of the rate. But it does take quite a bit of time to work on the rate, especially if the balance has to be adjusted in anyway. I think perhaps time might be better spent getting more watches to run well, rather than seeing how good each one can possibly keep time.
What do you think?
More about watch accuracy here...
See the whole album for this project here.
Hampden has an interesting keyless works, for winding/setting. It works well, and is also pretty closely related to a lever-setting relative.
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