So just a brief word about vintage watches, specifically as daily wearers. 
There are some that function quite happily in this category, and some that really.... don't.
Essentially this all comes down to how fragile the watch is, and the best examples of this are pocket watches. These watches are generally heavier than wristwatches, and when they get dropped, serious damage often occurs. F=ma. This is exacerbated by the fact that in many case, there is no shock system for these old balances.
Old wristwatches without shock protection are similarly at risk. We've all seen the old square, tank or tonneau watches from the 20s and 30s, basically most of these are sheet metal folded into a case. Despite any claims to the contrary, these watches are certainly NOT water resistant in any way shape or form, they are barely dustproof. Wearing one of these every day, depending on the environment, can be risky. Under the cuff of a dress shirt or taken out for special occasions, these watches can perform as expected, and that might be the best advice as to how to care for and respect these old-timers. 
Old-Timers. HA! I think that might be a watchmaker's joke...
There are always exceptions to this, some 30s watch cases are very robust, but they will lack shock protection. 
The Golden Era of watches is generally accepted to be the 50s and 60s, and most of these are good candidates for daily wear. 
HOWEVER! Keep in mind what your watch IS, that is, is it a rare and expensive thing for which parts are generally unavailable? Some watches are literally Museum pieces. 
When I first opened the shop away from the big city, we were still restoring 18 century Fusee and Verge Pocket watches. These are in general, extremely fragile, and I would always advise against any sort of daily wear, or any wear at all. They are generally much heavier than later watches, and parts for these are all hand made. I'm not saying they are not repairable, but I no longer undertake these repairs. Watchmakers who still do this type of work are few and far between, especially here in North America. 
Also keep in mind, any water depth rated watches, even dive watches, may not actually conform to the original standard, and if they are valuable, I do not recommend diving with them. The official line from Breitling is that a depth rated watch must come in every two years for water resistance service, to maintain the water warranty. That also means no hot tubs or showers, which void these warranties. 
The best analogy I can give is these old marvels of micro mechanical engineering are like old cars, treat them with care and respect. 
I mean, you wouldn't daily drive your model A, now would you? Or go off-roading with your Willys Overland? 
Ok, some of you would... but you get the gist.

Ok, just another word here about the ubiquitous quartz watch....

We do a lot of battery changes, and there are some things to keep in mind about quartz watches and batteries in general.
If you change the battery yourself, do NOT touch the battery with your fingers, use finger cots. Likewise, do not touch the watch movement itself or use a vise (or a hammer) to shut the snap back case. That last one is common sense, right?
RIGHT?
Anyway, we do see fairly regularly a lot of fresh batteries in watches that do not run, or fail soon after battery change, now why would this be, you ask?
Quartz watches are fragile, in some ways more so than mechanical watches. They are very susceptible to magnetic fields and radiation, and a strong magnet will kill a quartz dead. So you want to keep your quartz watch, or ANY watch, for that matter, away from cell radiation or other types of electromagnetic radiation and magnetic fields, ESPECIALLY cell phones. 
Quartz watches have a relatively short life, a cheap one maybe a year or two, the more expensive ones may last decades, but that's about it. Mechanical watches will last much longer. The average age of the ones in our showcase is 60-70 years old. The oldest one we ever repaired was well over 200 years old, and is still running today. 
Quartz watches, if left to die and thrown in a drawer, will tend to get sticky. The gear train may become stuck as the microscopic amounts of lube dry out and the plastic components degrade. The battery might also leak and make a real mess.
Putting a new battery in a watch that hasn't run in many years may result in a detectable pulse, but the hands don't move. It looks like the watch isn't running, but it is.
The quartz movement generates a weak impulse, and any friction or stickiness at all will mean that the circuit registers an impulse, but the rotor won't move, or the second hand won't move, maybe the entire motion works is too sticky to move. We have a machine that 'pushes' the gear train and makes the watch pulse rapidly, spinning the hands at a high rate. This sometimes unsticks the watch, and it will work normally.
Sometimes the watch is too gummed up. You can clean it out, but it is cheaper to replace the quartz movement, and a better idea too, because the new movement is fresh and has a warranty. Circuits fail, parts wear out, coils get touched.. There is a switch in the stem, so that when you pull it out, it stops the watch. It doesn't actually stop all electrical activity, but diminishes the draw so the battery isn't being subject to a full load. The switch eventually wears out, and the watch will stop and start intermittently.
This is actually quite common. Even a brand new Quartz watch, if left in a drawer for a couple years, will degrade markedly. Off-gassing of the plastic components will fog the inside of the crystal and degrade the parts and electronic contacts and wires. Swiss quartzes generally are better built, (They often have jewels) and will last longer, but they still fail much sooner than their mechanical counterparts. 
The footprint of Quartz watches is much larger than mechanical ones, and the recycling that must accompany them also contributes to environmental impact. At the end of a typical year, we have 5-10 pounds of button cells to recycle, and many more pounds of discarded cheap watches that cannot be recycled. 
I'm all about history and micro-mechanical engineering, so I love mechanical watches, which are still manufactured in large numbers and have a much smaller footprint to boot.
​Keeping your quartz watch running with fresh batteries and warm on your wrist will make it last longer than if it is neglected, kind of like if you parked your car for a couple years and didn't run it.

Just a quick word here about watch repairs and restoration, and when and why to do them.
For those that have extensive experience with this, you may want to skip this, but for anyone who is new to watch collecting or has only recently wondered IF they should restore Grand Dad's pocket watch, read on....

First, Grand Dad's or GrandMa's old pocket watch.
If it is not being wound and used on a regular basis, you need do nothing, it is only if you intend to run it regularly that you might want to think about a service or restoration. Sometimes just a wee display dome is all that is necessary for the family to see and appreciate the old workhorse that served for so many years.
A lot of old pocket watches may have less than 15 jewels, 7 being the most common low jewel count. In this case, extensive wear is usually found in the pivot holes of the plates, owing to the metal-on-metal wear associated with having no jewels as bearing surfaces. These types are the 'Model T' of watches, and originally cost less than their full jewelled counterparts. Wear at the pivot holes may require bushing of the plates, which leads to extra expense, and usually it is not worth it, but it depends on the maker, of course. 
Which brings me to the main point.
If you are thinking of trawling eBay for vintage watches with the intention of having them repaired or restored, keep in mind it is a lot like vintage automobiles. The better the starting example the better the result will be. If you start off with something in reasonably good condition, chances are the end result will be that much better. Start with something very worn and damaged, and not only will there be much higher costs to repair it, but the end result may be cosmetically poor, regardless of any refinishing.
So that cheaper version of the watch you're after may be cheaper for a good reason- it may be badly worn or worse- something someone has given up on, for very good reason. 
That said, you don't want the most expensive example either, the top prices on eBay are ridiculous, as anyone will tell you. 
Examine any and all pictures associated with the watch, they will tell you how it was treated. Dings, scuffs and scratches on the case are one thing, but if you see a lot of tool marks and damage on the movement, it might be wise to move on. We see a lot of butchered up movements, and sometimes the damage is beyond economical repair. 
It is also worth noting that the more expensive brands tend to get treated better, with good service records in keeping with the appreciation of their initial cost and preserving their value. 
Finally, it is usually better to buy old watches hands-on, at a NAWCC mart, for example. That way you can see clearly what you are buying, and ask questions about the piece with the seller right in front of you. Members of the NAWCC are usually very knowledgeable, and I can recommend becoming a member for anyone interested in collecting clocks or watches.
Happy Hols, everybody, and see you in the New Year!

​R

Ok, so I haven't increased my price on battery replacement in over ten years, but lately I have been considering pricing certain jobs higher than that because of PITA factor.
People often ask me 'How hard is it to change a battery?' and the answer is sometimes it isn't hard at all, other times it is a nightmare.
Curved cases require special dies and presses to close the case backs and some watches, like Bering and Skagen, are difficult to work with because the whole front of the watch is glass or sapphire. 
Really cheap watches, you can close the case with your fingers, but anything decent quality requires a press, or the screw down case backs require a proper case wrench or bench mounted closer, and then there are the gaskets to condition or replace.
Touching the battery with your bare fingers can and and will shorten the battery life and depending on the person's bio magnetic field, can cause leaks. 
You know who you are, magnetic persons !
I know this sounds a bit nuts, but some people have a lot of inductance or whatever it is, as well as acidic sweat, or they smoke, or various other issues.
Anyway, the proper way to handle a cell is with finger cots, which is what we do. 
Also keep in mind, that if your watch has a realistic and serious depth rating, with a screw down crown, it is advisable to replace ALL the gaskets every two years to maintain the rating and any warranties associated therewith, IF you care about such things, OR your watch comes into contact with water on any kind of regular basis, keeping in mind also that hot water voids warranties and no one should be showering with their watch on, as I've written about elsewhere. (This advice courtesy Breitling service centre)
Certain watches also require special procedures, like Seiko Perpetual Calendars, which may need to be programmed at every battery change. A warning here:
It is EXTREMELY EASY to destroy a Seiko Perpetual Calendar while changing the battery, because the cell sits on top of a VERY thin circuit board. Even programming it with a heavy hand can puncture the circuit points. 
We also use Swiss cells, which are a lot better than your average bulk purchase no name Chinese ones, just sayin'. 
I actively discourage anyone from buying really cheap quartz watches, because more often than not, they get thrown away rather than replace their cells, and at the end of the year we see garbage bags full of non-recyclable watches going into the landfill. Sometimes these watch cases are made from highly questionable metal and are toxic.
So how hard is it to change a battery?
Depends. When in doubt, see your friendly neighbourhood watchmaker.

Peace. Out.

​R

Ok, lately there has been a considerable uptick in the number of fakes crossing my bench, maybe there are seasons for this type of thing, I dunno. Some of the following is a re-iteration of parts of posts I have made in the past, so if it sounds familiar, that's why.....
A lot of fakes are blatantly obvious, like a watch that is supposed to be a mechanical and the second hand ticks in one-second increments because it is a quartz. I see a lot of fake Rolexes like this, and they are extremely cheap and awful. (Rolex did make an OysterQuartz that is now discontinued, but it it is very distinctive looking and says Quartz on the dial)
When someone deliberately misrepresents a watch as genuine, knowing it to be a fake, well, that is obviously FRAUD, and this has happened to friends of mine and customers recently. Money lost has been in the tens of thousands.
Without calling them out by name, there is a popular auction site that advises against doing side deals, that is, transactions outside the site because the site warranty and protections do not apply. This is good advice.
Nuff said?
As I have mentioned elsewhere, there are certain brands of watches that are harder to detect as fakes. Cartier, Breitling, and others use ETA and Sellita movements, (as well as their in-house ones) with Cartier or Breitling branding on them. If you take an ETA movement and put a Cartier engraved rotor on it, it will look a LOT like the genuine article. Fortunately, a good watchmaker can spot these, as the fit and finish (among other things) will give it away.
These are usually COSC certified chronometers, and that means they are the Chronometer grade ETA movements, which few fakers will go to the trouble of using. That said, I have seen ones that did go to that trouble, and the fake was virtually indistinguishable from the genuine article. What finally gave it away was the thread pitch on a certain part of the case was incorrect.
Thread pitch, that was it.
This lead to checking the serial number, and although it was a valid number, it did not jive with the watch's purchase date nor country of purchase, SO>
Another big giveaway is the serial or model number. Most fakers will not bother to use a genuine serial number and that is the giveaway, but beware that there are some who DO.
Metallurgical composition is another tell. However, stainless steel would rarely be tested for its composition, but gold often is. Something that is gold plated, obviously will wear and look bad, and is suspect especially where it is supposed to be solid gold. 
There are also watches that rarely use COSC chronometer movements, and these are the easiest to fake. An ETA movement in the lower grades is easy to engrave with the proper markings, but there are giveaways here as well.
Engravings and laser etched markings can be faked, even on sapphire crystals, so do beware.
I don't want to get into too much detail here, it would be too useful to someone looking to make a fake. 
The short version is, buy your seller, but sometimes even that fails. When it does, there are sometimes site warranties that protect the buyer, like you-know-who.
The Authorized service centres will of course tell you if your watch is a fake, but sometimes this only comes up when the watch is getting serviced, and some years may have passed since the purchase date. A certified watchmaker can identify a fake, but recently where this broke down was, a fake was sold as a new watch, and to open the case would void the warranty, so we did not do it. Turns out that the watch was indeed a very good fake, and the movement was a dead giveaway. 
There was a solid 18K gold ladies Rolex I saw in Calgary that had avoided detection as a fake for over 40 years. Because the case was solid and tested so, and the diamonds were good quality, no one questioned the authenticity of the entire piece. This one I still wonder about, obviously it was not serviced by a qualified watchmaker, as that would have revealed its bogus-ness. Or MAYBE the guy/store that sold it managed to be the one who serviced it faithfully, knowing full well it was a fake. 
I have heard sellers try and dismiss discrepancies by claiming 'Grey market' status of their wares, and be aware that a lot of these have no warranty whatsoever, even if they are authentic. 
Generally, Authorized Dealers are the safest bet, but certainly not the cheapest. Nothing is 100%, as I have seen even dealers and other high end jewellers get caught with counterfeit watches. I saw one recently with a very well known jeweller's name on the warranty card, but even the box and papers and card were all fake, fake, fake.
If it looks like a too-good-t0-be-true deal, it probably is, as the saying goes.
Let's be careful out there.

​R

I've been getting more inquiries about this, and were seems to be some confusion as to what happens during clock service.
First of all, in the case of all mechanical clocks, they require service every 8 to 12 years. Since this NEVER happens, the clock will run for decades until metal-on-metal wear causes it to fail, sometimes spectacularly. If the power of a wound mainspring is unleashed suddenly, as is the case with a broken wheel tooth or pinion tooth/stave, the backlash can destroy the clock movement.
Basically, for a mass produced clock this is game over, unless you want to spend an absurd amount of money rebuilding a wrecked movt.
For mantel clocks, because they are mostly portable, they are dropped off and serviced at your friendly neighbourhood clockmaker.
An Overhaul entails complete disassembly and cleaning in Industry Standard solutions, as well as hand cleaning of certain components. Mainsprings are assessed for wear and loss of modulus of elasticity, and replaced when necessary. The pivots on all wheels are polished and work hardened, and the plates are bushed to restore the precise geometry needed for optimum power transfer. The clock is now re-assembled and lubricated, and test run for regulation and timing. This includes not only rate adjustments, but also beat error correction and oftentimes in weight driven clocks, we find that the weights have been modified, so they need to be restored or repaired as well.
In the case of Floor clocks or Grandfather clocks, the mechanism is picked up and taken to the machine shop for overhaul. There is no way to perform the work in situ.
This brings me to the next point, if your long case or GrandFather clock is being serviced in the home, it is NOT being overhauled, usually this falls into the 'Quick Fix' category.
So what are examples of 'Quick Fixes?'
Lubrication, which should be done every 4-6 years, can be done in situ, but the dial and hands MUST be removed, and often the mechanism must be removed from the case. If the dial and hands did NOT come off, your clock was NOT lubricated correctly.
A complete lubrication requires the removal of the dial and hands, but a partial lubrication might only entail the escapement being done. 
If the clock does not perform properly after a lubrication, it is usually the sign that severe wear and tear have made an overhaul necessary. 
Other 'Quick Fixes' include regulation, Beat Error correction, Chime adjustment, and timing and regulation. Sometimes the chains get pulled right off the sprockets or they get jammed. Humidity changes can warp clock cases and sometimes you can correct for this by re-positioning the movement in the case wherever possible. 
I've come across quite a few recently that have been absolutely butchered in situ, and I do spend a lot of time correcting previous 'repairs' by 'Unskilled Hands,' shall we say. 
Anyway, we are the custodians of these often antique time machines, and they are one of the few actual antiques that can be still used on a daily basis in this increasingly tech oriented world. 

​R

Just a quick word here about the meaning and usage of the word 'Rare' as it pertains to watches and clocks.
Everybody's favourite auction site does tend to over-use the word 'rare', if you were to go by what you read there, 99% of all mechanical watches are 'Rare', or 'Unique.'
Unique means one of a kind, and obviously, should only be used when describing exactly that. 
So what about 'Rare?'
Most companies that produced mechanical watches in the last 150 years made a LOT of them, sometimes millions per year. Depending on what country you are reading this in, what we see everyday may differ from what is common where you are. Here in North America, we didn't see a lot of Cortebert or West End, but those companies made a lot of watches. In Britain you saw a lot of Smiths watches, and I see that the prices for these are rising steadily, eclipsing many Omega vintage watches. 
Which brings me to another point.
Don't accept as gospel the inflated prices you might see online. There is a slump in antique clocks right now*, and we stay in touch with many US dealers as well, who report the same thing. Pocket watches have taken a real nose dive as well, and in general the Industry is experiencing a lull. I don't know about the brands themselves and their new product, although certain well established makers seem to have no issues.
There is a lot of competition out there, and small companies pop up all the time, kickstarting their way into the market. If you look at the specs of most of these new mechanical offerings, you will see the same old ETA movts or their Sellita equivalents, followed by Citizen driven watches, usually the 9015.
(There has been a marked drop in the quality of some ETA movts, and in the case of the Sellita SW300, which is a version of the 2892 ETA, improvements have been made.)
Until other manufactures up their production to compete with ETA, unfortunately we will continue to see a lot of this.
There are still many gems to be had, watches that are under the radar, and when these start to get their just vintage due, the prices will rise. Watch manufacturing history is pretty convoluted, but it is well worth the time to find out about makers that either didn't advertise all that well or who are now largely forgotten. The Grand Daddy of them all is Eterna, watch that one. 
So definitely read the specs, (I'm talking new watches mostly here) and don't believe everything you hear or see, especially on Auction sites. That word 'Rare' is pretty common, and that mass-produced brand name watch might not be all it's cracked up to be. 

​R

*There is a slump in retail in general, and trackers of this sort of thing I have spoken to say we have been in a recession since 2018. I would agree with this, the past two years have been abysmal. 14Sep2019

Regular readers of this sporadic writing have heard me warn of the Achilles heel of Quartz watches- Magnetic fields, along with heat and leaky batteries, but the Mechanical watch has one also.
The staff of the balance in your mechanical watch has pivots that are very small, and they are hardened. They sit in a shock-absorbing assembly designed to protect them, but a good whack can and does shear them right off. 
The most common cause of this type of damage is dropping the watch, but it can also be from striking the watch inadvertently against a door frame, for example.
Now the above describes modern watches, but the older ones were even more fragile. Lacking any type of shock system, they are very likely to be damaged by any kind of shock, and that is why you see so many pocket watches with broken staffs. The shock systems were many and varied, but the one known as Incabloc, invented in 1934 by Georges Braunschweig and Fritz Marti of Universal Escapements Ltd., is nowadays the most common. There were many types of shock systems but they didn't show up right away in watches due to the extra cost. In a lot of brands, you don't see shock systems until the late 40's, and lower end watches still didn't have it in the 50's. 
Shock protection isn't infallible- it is still possible to damage the staff's pivots, but it gives a bit of extra leeway, as the balance can actually be displaced sideways without harm to a certain degree. 
Now many of you may remember the highly entertaining 'Timex Torture Tests' of the 60's, and may be wondering why they were so tough, being strapped onto water skis and thrown off bridges and other stunts.
The answer is that the design of the staff doesn't have finely turned pivots, but is a chunky rod with conical ends, that don't really break. This means that shocks will likely destroy the gears before it has any effect on the balance. It also means an increase in friction by a huge magnitude.
This was all ok, because Timexes were designed to be throwaway items, as most were riveted together and not made to be repaired. We've all seen the horrifyingly cheap watches at the checkouts or in the airport junk stores, and these take the throwaway aspect to insane lows- unknown base metals, in some cases Cadmium, and the lowest end components possible. We accumulate hundreds of pounds of these types of watches every year, and they are not recyclable. In some instances, we have detected watches that have mildly radioactive metal used in making the cases. This points to an insane lack of quality or safety control in certain countries of origin.
But I digress.
Don't drop your watch or smack it about if you can possibly help it, especially those ultra cool vintage pieces.

​R

Ok, this is going to sound a little odd, but hear me out.
Have you ever heard the expression 'The dirt was holding it together'?
Well, turns out that is almost true in some cases, particularly with clocks.
I run into this quite a lot, a clock hasn't been serviced in many years (99.99% of the time) and sometimes it runs ok, sometimes not. Sometimes it runs quite well, and here I encounter the 'Don't fix it if it ain't broke' kind of thinking. I assure you, this does not apply to a lot of mechanical things, it is better to be proactive and do preventative maintenance.
Clocks are a collection of geared wheels that are basically transmissions. The power from the weight or mainspring is transmitted to the regulating organ, the escapement. In clocks, this can be ancre type escapements like recoil or Graham dead-beat; (There is a dizzying array of clock escapements, some are outright bizarre) but also platform escapements that can be like what you find in watches- a balance wheel with a lever or cylindre escapement (on older clocks). 
The former utilize a pendulum that swings in an arc and is mathematically matched to the gear train to give the correct frequency. If you've ever watched a long case clock pendulum of a meter or so, you might have noticed how slow it is, compared to a small table clock, with a much shorter pendulum, say less than 13 cm.
The gears have pivots on each end of the arbors which pass through the usually brass plates. When no service is done, the oil dries out and dirt accumulates on the movt. Clocks are notoriously non dustproof, and this dust will collect right were you don't want it. ESPECIALLY where  there is oil or dried oil residue. If the movt has been soaked down with oil, the dirt collects everywhere and acts as an abrasive, destroying teeth, pinion leaves, levers, plates, anything that touches or slips during the running of the clock. 
This is why you cannot oil a dirty clock. It mixes with the dirt that is already there and this sludge pools in the oil sinks of the pivots. Additional dust then adds to this. In order to clean this out, you have to fully disassemble the movt, and by doing this, you are well into overhaul territory. This is where the clockmaker encounters wear and tear, and while the clock is apart is the best time to address this, obviously.
After many years (some clocks will run for 50 years unchecked) the residue of dried up grease and oil and dirt can harden into something that looks and acts almost like stone. I kid you not. I have chipped this away from plates many times. 
Corrosion also occurs, depending on the atmosphere around the clock, smoke being the number one destroyer of mechanisms. (Clocks from places where smoking was excessive are almost always wrecked) Excessive humidity is also bad, and there was an old myth about putting a jar of kerosene or something in the bottom of a long clock case to supposedly mitigate this.
Do not do this.
The vapour does indeed get around, and it sticks to the mechanism, and will form a sticky film. 
Oil or sticky films with dirt on the teeth of brass wheels will destroy them quickly, so you do not want this. Oil belongs in oil sinks, period. And sparingly at that. (the little dish shaped indentations around the pivot holes in the plate)
When a clock gets dirty and is run for many years, say decades, the dirt and corrosion and oxidization and dried up oil residue will begin to limit what is called the endshake of the wheels. Normally the wheels are free to move slightly laterally as well as turn on their axes. Endshake is absolutely critical, but you don't want too much or too little. Too little and the train is really tight and friction will overcome the force trying to run the clock. Too much and the movement is sloppy, and in wristwatches and pocket watches, endshake is finely adjusted in chronometers to make for a really good delta in positions, which is to say, the watch will run within a very tight tolerance, no matter what its orientation in space. Up, down, sideways, you get the idea.
Generally, clocks don't move, (Carriage clocks were designed to be carried) but if dirt starts to limit the endshake, and the clock is dirty, the engagement of the wheel teeth with their adjoining pinions is kept to a narrow space, and deep ruts will be carved into the steel of the pinions. The teeth may also suffer significant wear.
When the clock is all cleaned up and endshake is restored, the wheels are freer, but will encounter the ridges of the ruts and this will interfere with the running of the clock. This is why a dirty clock will sometimes be seen to run fairly well, and if the clock is overhauled it may suddenly seem to run less well. Usually the pinions are so worn that they now cause trouble.
So what does the clockmaker do about this?
Basically, the leaves of the pinions must now be careful stoned or ground to eliminate the ridges of the ruts chewed into them over many years. This involves removing a small amount of metal, and the pinion leaf must then be polished. Preservation of the shape of the leaves is also important. 
Each pinion will have 7 or more leaves, and there will be 4-6 wheels in each train, each with its own pinion. A Chiming clock has three trains, a Striking clock has two. A single train will be found in a Time-only clock like a regulator. Each leaf will be carefully repaired and then polished. Hopefully at the end of this procedure, the pinion is still within tolerance. If not, it must be replaced, and that can be.......expensive. This means that individual pinions must be cut, and this is a specialized service that is very hard to come by. On cheaper clocks with lantern pinions, (instead of leaves, the pinion has hardened wires like staves) the wires can be replaced. One by one, and this is quite tedious as we are working with blue rod and cutting and stoning the ends.....*
Lots of work, and takes lots of time to do it. 
So what do we want to do?
Why, 'Prevent the clock from getting so messed up!' I hear you say.
Why yes, that is what we want.
There will be a quiz next week.........

*If a lantern pinion fails, that means one of the staves has worn completely through and the clock will suddenly release all its energy, shearing off teeth, bending very thick steel arbors, and basically tearing itself apart. In cases like this, the clockmaker may recommend defenestration or dropping the clock into the canal. 

I've had some questions recently regarding the operation of an automatic watch. This technology goes back to the 20's, but a self winding pocket watch was made by Breguet in 1777, the same year a similar watch was claimed by Perrelet. Further claims were made by other watchmakers of the time, not the least Le Roy, but I'm not going to delve into that here, it is a hotly contested thing, being able to say you were first. Breguet still exists as a company, as does Perrelet.
An automatic watch utilizes a weight which moves with the motion of the wearer, and was at first a pendule type, followed by various designs that included 'wig-wag' wristwatches as well as 'Bumper' type weight systems.
The most common today is the rotor, or oscillating weight type. Not all automatics are created equal, I could fill pages with the history of the variations, but for the purpose of the blog, I'm just going to describe what happens inside your modern automatic watch, especially when you bring it in for service.
Generally, during a full service or CTR, the mainspring is one of those parts that gets replaced as a rule, regardless of its appearance. (For the purposes of this blog, I am talking about modern automatic watches here, which means mid 20c to present)
As I have pointed out elsewhere, overwinding is a myth, you wind your watch until it stops, if it is a manual wind. For an automatic, the motion of the wearer and subsequently the rotor inside, is what winds the mainspring. At some point, the watch is fully wound, so now what?
Adrien Philippe (of Patek Philippe) developed a mainspring with a slipping bridle. This end is not attached to the wall of the barrel as it is with manual wind watches, it slips on the wall of the barrel against a film of braking grease.
If the wearer is so active as to make the watch wind itself completely, the spring will slip, so that no damage is done to the mechanism. These springs are usually described in watch literature as 'unbreakable', but they do break occasionally. Usually the bridle end breaks off, but sometimes the spring will break right near the centre, at the winding arbor. 
So you wear your watch, the rotor spins around, and the watch winds itself. Green technology at its finest, no batteries or capacitors to worry about. 
The automatic mainspring looks like an 'S' shape when it is uncoiled, and is a very specially engineered spring. The outer coils are curved the opposite way of the centre, placing extra friction agains the barrel wall via the bridle. 
There are no fewer than 3 different types of lubrication in the barrel of a watch, and each does its job to mitigate friction. The barrel itself is smaller than a dime in most men's watches, even smaller in ladies watches. 
So that's it- your watch gets the full treatment and the spring is now brand new, ready to keep on powering the movement. A well cared for watch can last hundreds of years. Here is the spring uncoiled, next to the arbor around which it is wound:

​