Do mechanical movements really "break in"?

[Vizard]

Hi All

I picked up a Tissot PRX Powermatic 80 (35mm) last week.

It keeps good time, but has quite significant positional variations, with a spread of about 20s in different positions.

Also, the amplitude is pretty low on occasions - 160 ish and it has a beat error that goes from 0-2.5. Manually winding it gives a 300 amplitude briefly, but it quickly drops back to 220 ish.

I believe that the movement is a modified ETA with some polymer components - escapement and pallet fork I think.

So my question is, is there any point in waiting a couple of weeks in the hope that the movement breaks in? My gut feeling is no, but expert advice is appreciated.

 

 

[RichardHarris123]

It sounds like there are multiple issues and it won't improve with time but the more advanced on here may say otherwise. The positional and beat error issues are probably related to the balance. 

[Vizard]

What I am pondering is why the B/E moves so much. As I type, I am testing it dial down and it has a rate of +6 to 0 and a B/E of 0.7

Dial up, the B/E was all over the show.

What would be causing the variations? Lubrication?

I am not even sure how much I should expect from the movement. It's a basic ETA modified with polymer components. Perhaps an average rate of 0 is fantastic and everything else is a side show.

It does require, however, judicious overnight positioning (dial down) to address the OTW daily loss.

 

[RichardHarris123]

Broken bottom pivot maybe?  

[oldhippy]

Have you serviced it. If not then I would give it a complete service. 

[Vizard]

17 minutes ago, oldhippy said:

Have you serviced it. If not then I would give it a complete service. 

It's brand new, so that wouldn't be appropriate.

[nickelsilver]

Are you checking on a timing machine or an app? On a machine try changing the gain (you want the sensor in contact with the crown). Beat error can change with position. Amplitude as well. Amplitude will change with state of wind, but in horizontal with a new watch should generally be over 270. Do you know the lift angle?

[Vizard]

29 minutes ago, nickelsilver said:

Are you checking on a timing machine or an app? On a machine try changing the gain (you want the sensor in contact with the crown). Beat error can change with position. Amplitude as well. Amplitude will change with state of wind, but in horizontal with a new watch should generally be over 270. Do you know the lift angle?

I don't know the lift angle, and cannot find it by Googling.

The LA for he movement that the Powermatic 80 is based upon is 50. Though I don't know whether the Tissot modifications change that.

On the subject of the time grapher: Mine is the Weishi Chinese "homage" model. I have just read on another site that the Powermatic 80 is quite quiet and the cheapo graphers struggle with them. This would be supported by the fact that I am seeing a lot of "noise" on the screen.

 

 

 

 

 

[oldhippy]

3 hours ago, Vizard said:

It's brand new, so that wouldn't be appropriate.

Send it back or take it back it will be under guarantee. If you open it and fiddle around with the guarantee will be void. 

[Vizard]

8 hours ago, oldhippy said:

Send it back or take it back it will be under guarantee. If you open it and fiddle around with the guarantee will be void. 

I don't intend to fiddle with it. I am also not sure that it needs to be returned...yet.

The thing is, I am not yet convinced that the watch is "faulty".

Yes, the time grapher makes it look as though it is performing badly. However, I think there is reason for me to be a little suspicious of my grapher.

The Powermatic 80 movement is known to be a quiet movement. Also the Weishi grapher I believe is known to be not so good at the extremes of its duties as more expensive units.

The watch is running within 1 second per day on the wrist. It would be a case of taking it back and saying "this inexpensive automatic watch you sold me. It's running remarkably accurately. I demand my money back".

The response might be "you wot m8?"

I think for the moment I may keep a watching brief. 

I am also going to test the 80 hour power reserve claims. I am assuming that if the movement is running as badly as my grapher suggests the watch will struggle to get near 80 hours.

 

 

 

 

 

 

[oldhippy]

If it is preforming as you say it is with your timing machine it could be your machine. It doesn't make sense 1 second a day yet your machine is picking up all these faults. 

[nickelsilver]

I think this is a timing machine issue. There's a reason the Chinese ones cost 50x less than the Swiss ones; the Chinese ones are pretty good but not super good.

[Vizard]

As an experiment, I've just put my son's PRX 40 on the grapher. It's the same watch, but the bigger case. I ASSUME the same movement, but I am not sure.

His watch is about +2/day OTW.

His amplitude is about 20-30 degrees higher than mine. But the positional errors are still there. Dial up -2, crown down +10 - +12. 

Also crown down he has a B/E of 2.8.

So, two almost new watches that are running within 2s day on the rate and yet showing big positional errors on the grapher.

Hmmmmm....

[VWatchie]

As it is your personal watch, I would say not to worry too much about what you see on the timing machine. As @nickelsilver hints, TMs aren't all that reliable. I've had situations where my Chinese Weishi 1900 indicated 240 degrees amplitude when in fact it was 300 degrees. For more details you can check this and this post of mine.

I suggest that you put your timing machine on the shelf for the time being and instead investigate how the watch fares in the real world. I have been surprised several times by how well watches worked in real life, showing somewhat frightening results on the timing machine.

Wear and use the watch consistently for a few weeks and read how much the precision deviates per day. If the watch consistently goes a certain number of seconds too fast or too slow per day (give or take a few seconds), you know it's working as it should and then it's probably just a matter of you needing to regulate the rate.

 

[Vizard]

3 hours ago, VWatchie said:

As it is your personal watch, I would say not to worry too much about what you see on the timing machine. As @nickelsilver hints, TMs aren't all that reliable. I've had situations where my Chinese Weishi 1900 indicated 240 degrees amplitude when in fact it was 300 degrees. For more details you can check this and this post of mine.

I suggest that you put your timing machine on the shelf for the time being and instead investigate how the watch fares in the real world. I have been surprised several times by how well watches worked in real life, showing somewhat frightening results on the timing machine.

Wear and use the watch consistently for a few weeks and read how much the precision deviates per day. If the watch consistently goes a certain number of seconds too fast or too slow per day (give or take a few seconds), you know it's working as it should and then it's probably just a matter of you needing to regulate the rate.

 

 

So overnight I left the watch dial up. A position which the grapher says is -7/day. It was 2 seconds fast last night, it was 2 seconds fast this morning... no change.

You mention regulation. I think that movement is absent any regulator lever. You've to shift little weights on the balance wheel. It would REALLY need to be out for me to do that, it looks like a fiddle.

 

 

[VWatchie]

17 hours ago, Vizard said:

It was 2 seconds fast last night, it was 2 seconds fast this morning... no change.

That sounds like a very healthy mechanical timepiece! 

17 hours ago, Vizard said:

You mention regulation.

There seems to be no need! 

A watch can be precise but not accurate, and vice versa. Here's an interesting video about this topic.

 

Edited November 15, 2023 by VWatchie

[Vizard]

Thanks VWatchie, I'll take a look over the weekend.

 

 

 

 

 

[JohnR725]

On 11/13/2023 at 9:02 AM, Vizard said:

modified ETA

On 11/13/2023 at 11:40 AM, Vizard said:

I don't know the lift angle, and cannot find it by Googling.

The LA for he movement that the Powermatic 80 is based upon is 50. Though I don't know whether the Tissot modifications change that.

On the subject of the time grapher: Mine is the Weishi Chinese "homage" model. I have just read on another site that the Powermatic 80 is quite quiet and the cheapo graphers struggle with them. This would be supported by the fact that I am seeing a lot of "noise" on the screen.

Let's do a little googling because I need a model number. Googling gives us this

https://calibercorner.com/tissot-caliber-powermatic-80/

So if I guessed correctly why don't you try a lift angle of 47°.

Let's quote something from the website  Base Caliber ETA C07.111 (based on the ETA 2824-2)   From the website that I quoted this from if we look at the specs for the 2824-2 for instance we find that It has a running time of approximately 38 hours.

One of the problems that people often make is the assumption that the base caliber is the caliber with just some minor little modification. Except it usually is not and that will result in issues like availability of parts. So for instance what been changed on this watch well we know that it runs for 80 hours not 38 that's going to be a gear change and a new mainspring barrel. It has a synthetic escapement which by the way requires a special lubrication for the escapement. Plus a few other things have been updated and/or changed. Think of the base caliber as the base that something was built upon not something that had a minor tweak done to it.

 

Then I find the description cheapo quite interesting considering the Chinese 1000 and 1900 and my viewer outstanding purchase versus purchasing a witschi machine that will cost quite a bit more. Although it is quite a bit nicer timing machine but doesn't really matter which one you use if you're clueless over what you're trying to do for instance.

Then the problem was Swatch group is they don't like sharing their documentation. It is almost basically not available typically unless you try really hard to know the right people. So for instance

This is a older document as witschi has newer machines that I know would be a little time this. So think of this is a sampling which is telling us something all of the machines have the again sent to the maximum because this is a quiet escapement.

On 11/14/2023 at 6:57 AM, Vizard said:

You mention regulation. I think that movement is absent any regulator lever. You've to shift little weights on the balance wheel. It would REALLY need to be out for me to do that, it looks like a fiddle.

Ideally I would recommend not trying to regulate this watch. You're supposed to have some special tools something that goes under the balance rim so when you're rotating the timing weights you don't screw things up by pushing down on the arms.

[Vizard]

On 11/16/2023 at 10:25 AM, JohnR725 said:

Let's do a little googling because I need a model number. Googling gives us this

https://calibercorner.com/tissot-caliber-powermatic-80/

So if I guessed correctly why don't you try a lift angle of 47°.

Let's quote something from the website  Base Caliber ETA C07.111 (based on the ETA 2824-2)   From the website that I quoted this from if we look at the specs for the 2824-2 for instance we find that It has a running time of approximately 38 hours.

One of the problems that people often make is the assumption that the base caliber is the caliber with just some minor little modification. Except it usually is not and that will result in issues like availability of parts. So for instance what been changed on this watch well we know that it runs for 80 hours not 38 that's going to be a gear change and a new mainspring barrel. It has a synthetic escapement which by the way requires a special lubrication for the escapement. Plus a few other things have been updated and/or changed. Think of the base caliber as the base that something was built upon not something that had a minor tweak done to it.

 

Then I find the description cheapo quite interesting considering the Chinese 1000 and 1900 and my viewer outstanding purchase versus purchasing a witschi machine that will cost quite a bit more. Although it is quite a bit nicer timing machine but doesn't really matter which one you use if you're clueless over what you're trying to do for instance.

Then the problem was Swatch group is they don't like sharing their documentation. It is almost basically not available typically unless you try really hard to know the right people. So for instance

This is a older document as witschi has newer machines that I know would be a little time this. So think of this is a sampling which is telling us something all of the machines have the again sent to the maximum because this is a quiet escapement.

Ideally I would recommend not trying to regulate this watch. You're supposed to have some special tools something that goes under the balance rim so when you're rotating the timing weights you don't screw things up by pushing down on the arms.

That's a great answer, John. Thanks for taking the time.

[Vizard]

Well I don't know if this answers the question I originally posed, but after a week's use the amplitude of the Powermatic 80 has increased and hovers around 300 (with the time grapher on the default 52 degrees anyway. Nearer 270 with a lift angle of 47).

The beat error still isn't stunning, and it still has some positional errors. However, that is a boon in one way because the rate of the watch OTW is about -2. Crown down overnight it's about +2, so I can "Rolex regulate" overnight. The average rate is around 0.

For a cheapo auto watch I think it's pretty good.

 

 

Edited November 18, 2023 by Vizard
Accuracy