Day advance issue in Cal. 1022

GuiltyGear · Oct 6, 2025

Hi all. I'm trying to diagnose a problem with the day advance in a Seamaster Cosmic 2000, cal. 1022. The date advances without issue, both quickset (crown in first position) and every 24 hours. The day does advance in quickset (crown in second position, rotate crown away), but not every 24 hours. Most often it will advance partially, sometimes completely, and sometimes not at all.

This is a caliber that's much more than I can chew, but I'm giving it a try. The day star driver, date cam, and jumper lever are all plastic. There's no issue that I can tell with the date cam and lever though, since it advances and snaps correctly. The day star driver does look like a different design from what I'm seeing online, and it may as well be a replacement that doesn't properly catch on the day wheel teeth.

Any ideas would help.

Archer · Oct 7, 2025

What sort of balance amplitude do you have?

Have you serviced the whole movement?

What is the cannon pinion tension like - is it too loose maybe?

Have you properly lubricated the calendar parts?

Is anything binding?

Is there a chance some of the quick set parts are interfering during normal running, so not going back to where they should?

GuiltyGear · Oct 7, 2025

Not serviced. Not oiled. That's way beyond my reach. Just dipping my toes here.

Archer
What sort of balance amplitude do you have?

Mean of 200 in 3 positions (dial up, dial forward, dial down), with 0.4ms beat error. Lift angle 52.

Archer
What is the cannon pinion tension like - is it too loose maybe?

It is indeed too loose. The original issue with the watch was that when setting time, once the date advanced, it would start skipping. After moving the hands a few hours, it behaved normally. I reinstalled the day corrector and its spring, which originally seemed stuck on position. Also made sure the cannon pinion was sitting correctly. It hasn't had the skipping issue anymore.

Archer
Is anything binding? Is there a chance some of the quick set parts are interfering during normal running, so not going back to where they should?

It doesn't seem like so, to my untrained eye at least.

Archer · Oct 7, 2025

Probably not what you want to hear, but honestly it needs to be serviced with those amplitude numbers.

But if you insist, I would be looking at the cannon pinion first...making sure it has enough friction to drive the calendar properly.

ErichKeane · Oct 7, 2025

It seems the real question I don't see the answer to above:

IF you change the time with teh crown, and move past midnight, do both day and date change correctly?

WHEN it naturally (via ticking) gets to midnight, and fails to change over the day, does it ALSO stop the hour/minute hands?

If both of those are the case, it is definitely (to me at least) a loose canon pinion. Without those two things happening, I don't know the mechanism one could blame the canon pinion on, since time & day advance finger are 'connected' directly.

GuiltyGear · Oct 7, 2025

@Archer I don't mind. It was the plan all along to send it for a service. Simply thought to give it a try for that specific problem, just to get some knowledge. Before going in, I had no idea how a day/date mechanism works, and now at least I have a basic understanding.

@ErichKeane it did change with the crown before, but it started skipping as I explained here. Naturally (every 24h) it changed too; I believe without issues. Now it doesn't skip, but the day changes partially or not at all. Date changes fine. With "skipping", I mean that while I moved the crown to adjust the time, once it moved past 12 to change the day/date, I could hear a gear skipping several times. It moved the hands, skipped a few times, moved the hands again, and so on until a certain threshold (maybe 4-5 o'clock) where it started moving the hands smoothly again. It kind of feels that it was a combination of the loose pinion and date or day cams.

It is a good insight that I start first with the cannon pinion, since that's the root of the problem. With that resolved, I can debug (sorry, I'm a software engineer) the day driver and corrector, since those two are the only things touching the day wheel. I have to find a tool to slightly compress the ~1.4mm OD pinion though; the vise I have only goes to 0.9mm. Time for my favorite past time: shopping for tools 😂

ErichKeane · Oct 7, 2025

GuiltyGear
@Archer I don't mind. It was the plan all along to send it for a service. Simply thought to give it a try for that specific problem, just to get some knowledge. Before going in, I had no idea how a day/date mechanism works, and now at least I have a basic understanding.

@ErichKeane it did change with the crown before, but it started skipping as I explained here. Naturally (every 24h) it changed too; I believe without issues. Now it doesn't skip, but the day changes partially or not at all. Date changes fine. With "skipping", I mean that while I moved the crown to adjust the time, once it moved past 12 to change the day/date, I could hear a gear skipping several times. It moved the hands, skipped a few times, moved the hands again, and so on until a certain threshold (maybe 4-5 o'clock) where it started moving the hands smoothly again. It kind of feels that it was a combination of the loose pinion and date or day cams.

It is a good insight that I start first with the cannon pinion, since that's the root of the problem. With that resolved, I can debug (sorry, I'm a software engineer) the day driver and corrector, since those two are the only things touching the day wheel. I have to find a tool to slightly compress the ~1.4mm OD pinion though; the vise I have only goes to 0.9mm. Time for my favorite past time: shopping for tools 😂

Ah! yeah, wasn't clear what you meant by 'skipping'. Teeth skipping is a problem if it is actually that (and not seeing something else skipping), but I don't see anything obvious. MAYBE the tip of the plastic 'wheel pusher' is a little worn off, but not sure.

PS: Also a software engineer 😀 Its always those darn bugs!

GuiltyGear · Oct 7, 2025

ErichKeane
Also a software engineer 😀 Its always those darn bugs!

Gotta be careful with watches. I'm my own QA!

Archer · Oct 7, 2025

GuiltyGear
It is a good insight that I start first with the cannon pinion, since that's the root of the problem. With that resolved, I can debug (sorry, I'm a software engineer) the day driver and corrector, since those two are the only things touching the day wheel. I have to find a tool to slightly compress the ~1.4mm OD pinion though; the vise I have only goes to 0.9mm. Time for my favorite past time: shopping for tools 😂

First off, you need to disassemble the cannon pinion carefully. If you are unfamiliar with how to do that here is what I do...

Grip the outer part of the CP using a barrel arbor holder:

Place it on a solid surface, and use tweezers on the steel portion of the wheel - important that it is on this part and not the brass part of the wheel - to hold the assembly down firmly, then pull up on the outer part of the CP while twisting:

Then I would clean these parts, and apply a small amount of grease like Moebius 9504 to the inner pipe in the recessed area, and then press it back together - I press it together using a Horia jewelling tool:

I would just try this first before doing any crimping of anything. Then if it is still too loose, you can take it apart again and crimp the outer parts of the CP very carefully, and not a lot! Note that a CP that is too tight is a sure fire way to damage the minute wheel teeth and possibly the CP itself.

GuiltyGear · Oct 7, 2025

Appreciate you taking the time. I'm waiting on a couple of Bergeon vises (30022-1 and -2), so hope that can work. The barrel arbor holders are out of my reach for the moment. Was planning to wait on the jewel press and get something decent later on, not one of those cheap ones from aliexpress.

I would be crimping this tube? In theory, since this may be more than I can handle right now.

Archer · Oct 7, 2025

GuiltyGear
Appreciate you taking the time. I'm waiting on a couple of Bergeon vises (30022-1 and -2), so hope that can work. The barrel arbor holders are out of my reach for the moment. Was planning to wait on the jewel press and get something decent later on, not one of those cheap ones from aliexpress.

I would be crimping this tube? In theory, since this may be more than I can handle right now.

No - the other one.

GuiltyGear · Oct 8, 2025

Archer
Grip the outer part of the CP using a barrel arbor holder:

Are 1.5mm and 1mm arbor holders a good start? I can put them in my wishlist and get them when it makes sense.

lejaune · Oct 8, 2025

For this particular job, I find this guys method quite helpful if you don't have the special tools.

GuiltyGear · Oct 8, 2025

@lejaune indeed an approach that doesn't need many tools. Probably a bit risky for a beginner to grab it with a presto tool? Scratching or just compressing it if too much force is applied.

lejaune · Oct 8, 2025

GuiltyGear
@lejaune indeed an approach that doesn't need many tools. Probably a bit risky for a beginner to grab it with a presto tool? Scratching or just compressing it if too much force is applied.

I'm not a watchmaker. I have only done this once and it didn't cause compression. I didn't really inspect for scratches think that if there are, the hands will cover them.

Archer · Oct 8, 2025

GuiltyGear
Are 1.5mm and 1mm arbor holders a good start? I can put them in my wishlist and get them when it makes sense.

Yes, that's a good start - I have those 2 plus a 2.5 mm.

GuiltyGear
@lejaune indeed an approach that doesn't need many tools. Probably a bit risky for a beginner to grab it with a presto tool? Scratching or just compressing it if too much force is applied.

Not a real fan of this method, but it would work. If you want a more low tech method, this is what Omega recommends...

Using a block with holes in it, you invert the assembled CP in a hole like this:

You then use a small pin, 0.5 mm in diameter, to push the CP off the wheel through the hole. This will work but there are a couple of cautions...

1 - The tool you use to push the CP off cannot damage the inside of the CP - the seconds pinion goes through the very small hole in the CP and acts as a bushing to keep the seconds pinion centered, so you don't want to damage that.

2 - The hole in the block you use needs to be just the right size - ideally it would be just ever so slightly larger that the teeth on the CP, and the wheel would rest as much as possible on the steel portion of the wheel, to prevent possible damage to the brass part of the wheel.

The reason I don't use this method is that the hole that fits best is just too large for my comfort, and also the block I have is not perfectly flat on top - it is slightly convex. If you could get a nice flat piece of steel, and drill a precise hole in it this would be a good method IMO.

lejaune · Oct 8, 2025

Please correct me if I am wrong. After re-read the OP, if the date change happens every 24 hours but the day change does not, it's unlikely caused by the loose canon pinion. If there is any slippage in the canon pinion, the slip would equally affect the date ring and day wheel. Furthermore, the slip would stop the minute and hour hands.

Archer · Oct 8, 2025

lejaune
Please correct me if I am wrong. After re-read the OP, if the date change happens every 24 hours but the day change does not, it's unlikely caused by the loose canon pinion. If there is any slippage in the canon pinion, the slip would equally affect the date ring and day wheel. Furthermore, the slip would stop the minute and hour hands.

As I said, the movement needs to be serviced really, but if you are chasing a calendar issue, and know that the CP is already somewhat loose as the OP has confirmed, that is the place to start. It doesn't mean it's the place you finish.

The thing with troubleshooting is that you need to be methodical - if you just go in looking for the one thing that is the quick fix, you will often be frustrated, because it's very often more than just one thing.

ErichKeane · Oct 8, 2025

lejaune
Please correct me if I am wrong. After re-read the OP, if the date change happens every 24 hours but the day change does not, it's unlikely caused by the loose canon pinion. If there is any slippage in the canon pinion, the slip would equally affect the date ring and day wheel. Furthermore, the slip would stop the minute and hour hands.

The date could take less effort to change, and thus be less 'resistance', so a loose canon pinion could succeed in one but not the other.

That said, Archer is right, trying to identify something as the cause without fixing what you know about is a bit of a fools errand in something as interconnected as the watch.