A step back and a deep breath, Slava 2428 calendar issues

[Bearman]

Currently taking a step back and a very deep breath. I've a Slava 2428 movement the second one I've worked the first one went so well and it keeps fantastic time I thought I'd give another watch with the same movement a go.

I know the forum gets a lot of questions along the lines of why has my watch stopped, I hope the below describes the problem and what I've tried.

The problem is, it stops at 9:25pm exactly every time. What I mean by stop is that hour and minute hand stop yet the second hand keeps on going. I tried experimenting by advancing the time beyond 9:25pm by around 5mins until eventually reached 11:55pm and at which point it started on it's merry way again (date and day changing over) until 9:25pm. It will run fine all day keeping great time.

Firstly the watch winds fine, the hands move freely clockwise and anti-clockwise. Manually advancing the day moves freely as does the date both of which change at midnight with a satisfying snap. The date quick set works great.

I've had the watch apart twice since suspecting the calendar works and then deeper in to examine all the wheels for damaged teeth. The calendar works are all good, all moving as it should. Again all the teeth on every wheel are there as they should be.  

I have two wild theories as to the problem. Number one is that perhaps there's not enough torque/power in the mainsprings to drive the calendar works. Is that a symptom? Or an issue with the cannon pinion perhaps.

But before I go into dismantling the watch again I thought I'd seek the wisdom of the forum. Has anyone come across this problem or one like it before? Thanks in advance for any suggestions or advice.

[HectorLooi]

I don't think it's the cannon pinion as it would cause your watch to stop every hour. Try removing the calendar works and run the watch. If it works fine then that confirms your suspicion.

[watchweasol]

Hi  I take it its ok at 9 25am and on wards untill the 9 25pm point, First in line is the remove the extras as mentioned by Hector re fitting the hands and observe the action over time

[Bearman]

Hello both, thanks for answering. I was at a point where this watch is driving me nuts (I've had a number of issues, which I've overcome) and clearly I'm going to learn something from it. Hence the query, always good to shout out if in doubt.

Yes, it runs fine before 9:25am and there after all the way to 9:25pm where it stops.

I've now removed the extras which operate the day/date change over. It's had a test run past what would have been 9:25pm and as expected it worked. I then reset it back to current time and I'm going to leave it a full 24hrs just to make sure nothing else strange happens.

I'll keep you posted. In the meantime I think I'll the mainspring barrels out of a door movement I've got in preparation.

Thanks again

[HectorLooi]

What kind of amplitude are you getting on the timegrapher now?

When it stops at 9.25pm, is the balance wheel still moving or does it stop?

Some close up photos of the calender works when it stops at 9.25pm would be helpful. 

[Bearman]

Hello HectorLooi, Sadly I don't have a timegrapher, something I look to invest in at some point in the future.

When it stops at 9:25pm the balance is still moving as is the second hand. Though the minute and hour hand stop. This is the thing that's got me flummoxed. If it stopped I would have expected everything to stop.

I'll post some photos of the calendar works soon, currently it's under test. It's been running all day without fault, keeping great time (calendar works extras removed) but I'll soon see later in the next two hours when hope it rolls past 9:25pm. That would have been a full 24hrs. 

[HectorLooi]

Sounds like you have a loose cannon pinion. When you pull the winding crown out to adjust the time, do you feel the usual amount of resistance or does it feel very loose?

[Bearman]

I eventually got round to taking a photo of the calendar works, after fixing the TV. Priorities and the such. Had more luck with that.

In the picture it's missing the wheel that drives the works. That's in the other pictures for completeness.

I've been contemplating the cannon pinion again.

Yes it does feel loose when comparing to other watches, very subtle though. Subjective, but certainly looser. I think I'll try swapping that first and see what happens. I'll let you know.

[DFKG]

Hello, I am in the middle of rebuilding the same movement. My thought is. Are both barrels wound the correct way? Some times it can be deceiving on the 2428 because some of there barrels had a lid top & bottom so can only tell top from bottom by the exterior teeth. So winding a spring the wrong way is quite possible I presume. I also presume that the springs are both wound the same way in both barrels? If the second barrel in the line is wound the wrong way you wouldn't automatically know until it runs badly as the first barrel would wind ok and hold its power. But the second barrel would just keep unwinding.

 If anything I have said is incorrect please don't hesitate to say something as I am only a novice in this wonderful world and would appreciate the knowledge. 

All the best, D

[Bearman]

Hello DFKG, I'm very much a novice myself still. At it just over a year, and I must admit this movement challenged me the most to date. My issue was/is a loose cannon pinion, I'm looking to have another crack at it probably in the next few weeks.

It was good to see the issue manifest itself, as it was a valuable learning experience. If it all went to well I'd never learn.

From memory I think both barrels wind the same way. I'd take photos as you disassemble or note down which way the mainspring is oriented in the barrel when you pop the lid off. If uncertain only do one at a time to be sure, as not to mix things up.

Do you have any photos of the watch/movement? Is it one of those 26 jewelled versions or a later 21 jewelled one? 

Good luck