Dumb question from Noob about automatics and winding

Wryfox · Mar 18, 2017

I figure since I'm new here I'd get the dumb questions out of the way now so I can seem smarter later on....

I've owned automatics forever (if your read my intro post...40+ years now) but never really understood something about them.

What happens after the watch is fully wound? Isn't the slipper mechanism a wear component of the watch, and if so I would think its quite a sensitive aspect of an automatic. But it can't be because I never seem to see any issues with this. Things such as shock, excess lube (or lack thereof..actually, is this lubed or not?...hmmm). If it wears, you lose the ability to wind, or at least lose reserve time as it can't fully wind. If it binds(excessive friction), bad things I'm sure can happen, right?

Automatics are so reliable when it seems this aspect would be so sensitive to many tolerances, including environmental.

Don't get me wrong, I get HOW an automatic works, just not WHY it works so well.

Foo2rama · Mar 18, 2017

It would be safe to say most if not all automatic watches have a slipping clutch of some type or other mechanism to prevent overwinding. Otherwise the weight of the rotar might be enough to damage the mechanism.

j.allen · Mar 18, 2017

Yes the braking grease on the barrel wall keeps the clutch from slipping until a certain amount of tension has accumulated. I have a Seamaster that I can actually feel the mainspring violently slipping periodically. It's seems something is up with the barrel lubrication as it's not slipping soon enough. I have yet to investigate it and haven't worn it in many months.

Archer · Mar 19, 2017

Wryfox
I figure since I'm new here I'd get the dumb questions out of the way now so I can seem smarter later on....

I've owned automatics forever (if your read my intro post...40+ years now) but never really understood something about them.

What happens after the watch is fully wound? Isn't the slipper mechanism a wear component of the watch, and if so I would think its quite a sensitive aspect of an automatic. But it can't be because I never seem to see any issues with this. Things such as shock, excess lube (or lack thereof..actually, is this lubed or not?...hmmm). If it wears, you lose the ability to wind, or at least lose reserve time as it can't fully wind. If it binds(excessive friction), bad things I'm sure can happen, right?

Automatics are so reliable when it seems this aspect would be so sensitive to many tolerances, including environmental.

Don't get me wrong, I get HOW an automatic works, just not WHY it works so well.

Not a dumb question at all - many people on forums refer to some vaguely described clutch that they don't understand well, so this is a topic that I cover every so often so people understand what that really is a bit better.

The "slipping clutch" that people on forums refer to makes it sound very complicated, but it's not. In a typical manual winding watch, both ends of the mainspring are connected to something. The inner part wraps around and hooks to the barrel arbor, and the outer end of the spring hooks into the wall or floor of the barrel depending on the type of end on the spring. Historically there have been a large number of designs for hooking the outer end of the spring in place, so here is a chart showing a few:

In an automatic watch, the mainspring is only hooked on the inner coil to the barrel arbor - the outer end slips freely in the barrel. If you look at the mainspring from this automatic watch on my bench in front of the parts tray (Omega Cal. 1020), you will see the outer coil on the left end has another piece attached to it that forms a "Y" at the end of the spring - this is the bridle:

The spring must generate tension to provide torque, so a freely slipping mainspring inside the barrel will slip before it allows the spring to fully wind up to the proper tension. Having that extra piece of mainspring at the bridle helps create more friction between the barrel wall and the end of the spring. But that's still not enough, so we apply a special grease to the inner wall called braking grease - rather than cause less friction, it causes more, so it helps control the amount of slippage - here it is applied to the inside wall of a barrel on the same watch - this line of black grease at the red arrow:

The amount of grease here is important - too little and you will have low balance amplitude due to lack of power, and too much and you could cause excessive amplitude and that can cause things like rebanking (and a very fast rate). Many modern barrels (particularly Swatch group product) will also have small indentations on the inside wall of the barrel that helps stop the spring once it starts to slip - this prevents the slipping from going too far.

Although it's not really a common problem, if a watch is neglected, the barrel can wear on the inner wall where the spring slides. Here is a side by side shot of a brand new (left) and worn (right) Rolex Cal. 1575 barrel drum:

On the right I've added an arrow to show the groove that is worn into the barrel wall from lack of service over the years. If properly maintained, wear usually isn't a problem here, but there are always those "if it ain't broke don't fix it" guys who refuse to believe that the watch is wearing itself out if it seems to run okay, but this is the sort of thing that results from lack of servicing.

Hope this helps.

Cheers, Al

Wryfox · Mar 19, 2017

Archer
Not a dumb question at all - many people on forums refer to some vaguely described clutch that they don't understand well, so this is a topic that I cover every so often so people understand what that really is a bit better.

The "slipping clutch" that people on forums refer to makes it sound very complicated, but it's not. In a typical manual winding watch, both ends of the mainspring are connected to something. The inner part wraps around and hooks to the barrel arbor, and the outer end of the spring hooks into the wall or floor of the barrel depending on the type of end on the spring. Historically there have been a large number of designs for hooking the outer end of the spring in place, so here is a chart showing a few:

In an automatic watch, the mainspring is only hooked on the inner coil to the barrel arbor - the outer end slips freely in the barrel. If you look at the mainspring from this automatic watch on my bench in front of the parts tray (Omega Cal. 1020), you will see the outer coil on the left end has another piece attached to it that forms a "Y" at the end of the spring - this is the bridle:

The spring must generate tension to provide torque, so a freely slipping mainspring inside the barrel will slip before it allows the spring to fully wind up to the proper tension. Having that extra piece of mainspring at the bridle helps create more friction between the barrel wall and the end of the spring. But that's still not enough, so we apply a special grease to the inner wall called braking grease - rather than cause less friction, it causes more, so it helps control the amount of slippage - here it is applied to the inside wall of a barrel on the same watch - this line of black grease at the red arrow:

The amount of grease here is important - too little and you will have low balance amplitude due to lack of power, and too much and you could cause excessive amplitude and that can cause things like rebanking (and a very fast rate). Many modern barrels (particularly Swatch group product) will also have small indentations on the inside wall of the barrel that helps stop the spring once it starts to slip - this prevents the slipping from going too far.

Although it's not really a common problem, if a watch is neglected, the barrel can wear on the inner wall where the spring slides. Here is a side by side shot of a brand new (left) and worn (right) Rolex Cal. 1575 barrel drum:

On the right I've added an arrow to show the groove that is worn into the barrel wall from lack of service over the years. If properly maintained, wear usually isn't a problem here, but there are always those "if it ain't broke don't fix it" guys who refuse to believe that the watch is wearing itself out if it seems to run okay, but this is the sort of thing that results from lack of servicing.

Hope this helps.

Cheers, Al

Archer, you are both a Scholar and a Gentlemen. Thank You and the pics are just amazing.

For the record, I have heard so much BS about maintenance...either being a scam for the dealers to make money, to every 2yrs maintenance or hell to pay! Just last month I stopped by one of the most prestigious watch and clock shops in my area (family business, been around 80yrs). I had a great conversation with the owner about all manner of timepieces. Felt like kismet so I asked him about maintenance, and he said point blank it was a scam to make revenue. He said he doesn't put that on his customers, but if it would make me feel better, he would do it (but since his watchmaker retired 2yrs ago, he would have to send it out.....rats). He said matter of factly that it only needs a service when somethings wrong, and that's that. My guess is that trying to charge someone $600 to service a watch that is working fine, to get back a watch that works fine, is a tough sell in todays world.

So what's nice is that you actually have facts, not opinion. If the service costs weren't so dang high, it would be easier to say maintenance makes sense. I know I must sound like a neanderthal, but I have so many vintage watches, the expense of servicing regularly is just simply not going to happen. I imagine with so many collectors on this site, this must be a common debate.....

Thanks Again, Archer...great stuff!

Mouse_at_Large · Mar 19, 2017

It's the old debate about maintenance. I worked for a fair few years in the oil and gas industry, and saw some maintenance philosophies go from scheduled ->condition based -> breakdown and repair only depending on the price of oil and just how much an asset manager wanted to screw out of a particular installation to make his revenue mark before moving up the hierarchy. I worked for a couple of years on a project for an Oil Major that arose directly from the third philosophy and ended up costing millions in remedial works. Happy days 😁

YMMV

Archer · Mar 20, 2017

Wryfox
He said matter of factly that it only needs a service when somethings wrong, and that's that.

Glad you found the post helpful. With regards to maintenance and how often to service a watch, the primary thing that I try to stress with people is that there is no one rule that covers all circumstances. People will have very dearly held beliefs that no matter what you say, it won't change their minds, and I'm fine with that. If someone doesn't want to service their watch, I really don't care - there are enough watches out there that need service to keep me busy for several lifetimes, so I'm not worried about "scamming" people into doing services that really aren't needed. If I only took in watches that had completely stopped running I would still have far too much work, so I do chuckle when people say servicing is just a big scam by watchmakers to stay busy. If you are anywhere near a decent watchmaker, you will have more work than you can ever do.

If someone asks me how often to service a watch, my answer will be different depending on the watch, and who you use to service your watches. In many cases if it's a modern watch, if parts are readily available, and you use the brand service center for service, it may make great financial sense to let it run until it stops. Many replacement parts are already built into the cost of servicing at a brand service center, and since they used unskilled labour for many parts of the service process (all but the movement) they can keep labour costs down. They can also lose money on a number of service jobs, and make it up on many others due to the sheer volume they do.

So if you have a modern automatic, say it's ETA based, and you use the brand for it (let's use Hamilton as an example) then by all means run it into the ground and likely it won't cost you anything extra when service time comes.

But if you have a vintage Speedmaster with a Cal. 321, or a vintage Omega bumper automatic, or even a Cal. 500 series, parts for those are scarce, so your priority should be preserving the good parts that are inside the watch, because finding replacements will take time and a lot more money than parts for an ETA 2824 will cost. In this case letting the watch run and wear itself out will cost you dearly.

Now the above is just the financial side of things really. If you see servicing as a purely financial proposition, that's fine. However some people have a different approach, and want to take care of their possessions (a less common trait in today's society than it was in the past). Some people can't stand wearing a watch knowing that it is chewing itself up inside. This is where the definition of "needs service" gets to be subjective and contentious. When does a watch need service? Not talking about the recommended service interval, but the point technically when it needs to be serviced. To me this is when things like the oils drying up are no longer protecting the parts from excess wear, or the performance is so bad that the watch is not fit for purpose any longer.

I often hear that as long as nothing is wrong with the timekeeping, the watch must be fine inside...that's not true at all. First there are typically areas is a watch that are not related to timekeeping that can be wearing out, and as the example I posted in this thread, a watch can run incredibly well even though all the oils have completely dried up:

https://omegaforums.net/threads/if-...-does-that-mean-it-doesnt-need-service.20475/

I could show you hundreds if not thousands of pictures of worn out parts inside watches that were neglected. Opinions of people who don't know any better, and people saying service is just a scam to make money can't defy good old physics. Unless properly maintained, parts wear. Period.

Hope this helps.

Cheers, Al

Wryfox · Mar 20, 2017

Archer
Opinions of people who don't know any better, and people saying service is just a scam to make money can't defy good old physics.

Wonderful info again Archer! Thanks

My problem with hearing that service isn't necessary, isn't from other watch collectors, its from a guy(again, the local guy, but he's not the first) who's in business to make money selling and servicing watches. That's when I take pause from just opinion. He has everything to gain from saying yes I should service everything, but he didn't. Fundamentally I understand all moving parts wear, and also completely understand the argument for protecting rare movements, and not so much for new ones that can be replaced. In fact, my local guy alluded to the fact that he can buy a new movement cheaper than someone would charge for a full service of an existing one, Clearly he wasn't taking about vintage movements but I understand his point. It's all about value for price paid. I have a number of good vintage watches. It took a long time because I don't buy very often. I assume a vintage watch hasn't been cared for and price it accordingly. If their willing to accept my price, great...vast majority don't. I think I've bought four watches in the last year, but probably made well over 100 offers. I've assumed the worst state, and ended up with good values.

Great example from last week. Took my car in to have tires rotated. They also checked the alignment...they said every measurement was off. My question was "ok, so how much matters?" They asked me if it drove ok..straight and vibration free? I said yes. They said "then it doesn't matter". Right. I have enough to worry about in life that does matter. Same with the AC guy..I bought 6 month servicing(2x/yr) to make my wife happy. He comes one time to do servicing, we had a good conversation going and I ask him what he does and if its worth it? He told me point blank there is nothing they can do to prevent a failure, they are there to just look for problems to fix. So your not doing any preventive work? Nope. I asked him why am I paying for a "service". He said he didn't know, the company just offers it. He also said If I have a problem, I'll know it and know it fast, so just call when it doesn't work. So I was paying for this guy to come to my house to look for problems I know I don't have.

I guess by now y'all know which camp i'm in. My choice, knowing the risks. I'm ok with that.

PS: So despite above, I did think it would be fun to try to learn what I could do myself to help my lot without paying anyone else, so I've studied up on things and thought the easiest thing I could do was regulation. I started by using a smartphone app. I debated long and hard on whether to step up to a Timegrapher. For a long time I though its better to not know what I don't know. What if I find out my favorite Rolex has a crazy beat error? It worked fine in my ignorance and I loved wearing it. But if I knew something was off, would that change how I saw it? Got it anyway, and yup, it did change how I saw some pieces. Their perfection in my mind has eroded in many cases, but been happily surprised in a few. I'm reminded of an old african proverb..."All truth is good, but not all truth is good to say".

Archer · Mar 20, 2017

Wryfox
My problem with hearing that service isn't necessary, isn't from other watch collectors, its from a guy(again, the local guy, but he's not the first) who's in business to make money selling and servicing watches. That's when I take pause from just opinion. He has everything to gain from saying yes I should service everything, but he didn't.

Some things to consider...

1 - Because someone is in the business, doesn't mean they know what they are talking about.
2 - Most of these places offer service only as a courtesy to people, not as a primary part of their business, and most send all their work out to trade watchmakers who are under considerable time and pricing pressure (this means the work is often not very well done). Most see having to deal with servicing as an annoyance, rather than a profit center.
3 - I would take issue that someone who's primary income comes from selling watches has "everything to gain" by emphasizing servicing - there is a reason when you buy a new watch the guy trying to make the sale is not telling you that it will need regular servicing and that this servicing will be costly...they would sell a lot fewer watches if they told all their customers that at the time they were considering a purchase.

I'm not out to change your mind - again I really don't care if you don't service your watches - as I've said to others you can smash it with a hammer for all I care. The people I'm concerned about are those that read information like your watch seller friend told you, and believe it applies to all watches equally. It doesn't.

Cheers, Al

PS - the "replace with new movement instead of servicing existing movement" argument has some validity certainly, but only if the new movement is really new and has been properly sealed and stored (in a foil pack with inert gas). Most movements are packed in a way where they are not dated, not sealed, and were meant to be used straight away. The movement could have been sitting on the shelf for years and sold as new...again this is all ground I have covered before.

Wryfox · Mar 20, 2017

Archer
2 - Most of these places offer service only as a courtesy to people, not as a primary part of their business, and most send all their work out to trade watchmakers who are under considerable time and pricing pressure (this means the work is often not very well done). Most see having to deal with servicing as an annoyance, rather than a profit center.

This is a very interesting comment....probably because my field is industrial equipment, where servicing is a major profit center,% wise way above the initial capital sell. I'm translating that view of the world to the watch world and figure it has to be profitable there too. What could be easier than a watch seller taking a watch in for service, filling out a receipt, send it off, receive it back, collect money (and take their 10,20,30%..whatever). Seems like easy money rather than an annoyance.If they're not going to sell a watch, might as well make some on the easy service admin. There must be something I don't see.

FREDMAYCOIN · Mar 20, 2017

One of the best things is to find a trained/certified watchmaker to do business with directly. My watchmaker charges me anywhere from 75 to 200 u.s dollars for service depending on the complication. what really is discouraging is when you use a middleman(jewelry store/watch dealer) that send your watch to a watchmaker and charges you 300-600 dollars and pays the watchmaker half.

Archer · Mar 20, 2017

Wryfox
There must be something I don't see.

Yep there is...supply of watchmakers being a big one. Compared to mechanics, watchmakers are as rare as hens teeth, in particular those who do a good job. Another is access to spare parts - even on modern watches access is becoming more and more restricted, which means more and more hassle to get what you need to service a watch properly, and this adds to the time and expense. Both of these things above lead to angry customers - when the watch comes back after your guy has serviced it and there's a problem, he doesn't get mad at the guy you sent it to, he gets mad at you.

If you send it back to the service center for the brand, sure you get a cut, but when they scratch up the case back and leave lint on the dial, again your customer doesn't get mad at the service center - you are the person in front of them representing that brand, so you are the target. So you send it back again (most brand policies including Omega have you covering the shipping as the dealer, by the way) and your profit margin goes down, and your time invested goes up.

There's no such thing as a free lunch...

ChrisN · Mar 20, 2017

Wryfox
Great example from last week. Took my car in to have tires rotated. They also checked the alignment...they said every measurement was off. My question was "ok, so how much matters?" They asked me if it drove ok..straight and vibration free? I said yes. They said "then it doesn't matter".

If I were you, I'd go to a different garage. There is a tolerance on everything which they could have looked up and that was calculated by the design engineers. The mechanics don't have the skills or knowledge to make this call on their own. You might as well ask your gardener. I hope you don't have any serious problems or failures in the future due to their advice.

Chris

Wryfox · Mar 20, 2017

ChrisN
If I were you, I'd go to a different garage. There is a tolerance on everything which they could have looked up and that was calculated by the design engineers. The mechanics don't have the skills or knowledge to make this call on their own. You might as well ask your gardener. I hope you don't have any serious problems or failures in the future due to their advice.

Chris

They were being practical, as was I. The machine calculates everything for them. Shows measurements in red digits for out, green for in, and the spec range next to it. Everything was just a wee out, but more importantly, evenly. Jeep with mudders. The tires aren't going to wear evenly anyway. So all they cared about (and I agree) was how it drove. This is why its a good example. It wasn't prescriptive or by the book. What mattered was the impact (does it drive ok), not whether it was in spec. Same for me and watches. A good watchmaker could open every vintage watch I have and find a reason to work on it. Does it matter? Probably not...the watch runs ok, to me.

ChrisN · Mar 20, 2017

I don't think it matters what you do with your watches - the worst that'll happen is you'll be late for an appointment. If you don't service them, then as long as you mention it when selling, there's no harm done. Just means the next service may involve more replacement parts.

I don't know how many suspension systems you've designed but, you've made a call based on something. Suspension design is not trivial and takes a significant time using qualified and experienced Engineers plus a great deal of testing. You're driving a one or two tonne vehicle that you've openly declared is not roadworthy so, if you're involved in an accident, you could be in serious trouble. "The book" is there for a reason and your perception that everything is fine is just that, a perception.

Chris

Foo2rama · Mar 20, 2017

Does it help that read the comments in alignment and passed out from shock horror and fear???

How far out of spec? What kind of car? Uneven tire wear? How olds the car? When was the last time you got new bushings?

Driving straight with no vibration means nothing. I ran a tire to the cords with the other with minimal wear and the car drove fine. I was lucky to catch it and not have a blow out. I blame a shitty alignment shop that took shortcuts and ultimately paid for new tires.

Bad toe can cause nasty handling under breaking esp panic braking.

Not something you want to mess with.

ChrisN · Mar 20, 2017

Archer
as I've said to others you you can smash it with a hammer for all I care.

I want to use this as my motto from now on😁😁

Wryfox · Mar 20, 2017

ChrisN
You're driving a one or two tonne vehicle that you've openly declared is not roadworthy so, if you're involved in an accident, you could be in serious trouble.

Me and millions of other jeep owners with aftermarket parts, ALL of which no longer meet the mfr specs. Guys, its a matter of degree. If roadworthy meant within mfr specs, 90% of cars in this country would fail.

Drives fine, turns fine, stops fine, decent tire wear(remember I said mudders). That's my point. Say if the spec is -.30 degree and the reading -.31degree, catastrophe is not imminent. I'm not worried about it, but I do appreciate your concern (seriously).

Deafboy · Mar 20, 2017

Archer
called braking grease - rather than cause less friction, it causes more, so it helps control the amount of slippage

Here's an interesting website that details watch lubricants and greases. In the case of automatic barrels, the grease has the property of friction varying with load. So when the spring is fully wound the friction drops so further winding causes the spring to slip. Clever!

Dumb question from Noob about automatics and winding

Wryfox

Foo2rama

j.allen

Archer

Wryfox

Mouse_at_Large

Archer

Wryfox

Archer

Wryfox

FREDMAYCOIN

Archer

ChrisN

Wryfox

ChrisN

Foo2rama

ChrisN

Wryfox

Deafboy

Similar threads

Dumb question about case back gaskets