Rotary mp00712 running too fast

[DeepSet]

Hello!

I have a Rotary mp00712 skeleton pocket watch. It was bought for me as a gift several years ago. I love it but it runs a bit fast (several minutes gained per day). My other pocket watch has a very clear lever in the back with a +/- adjustment, but I havent been able to find an equivalent on the Rotary one.

I have managed to unclip the glass (front and back) to see if there was an adjustment that I couldn't see, without success. It was hard work getting the glass to clip back on - any technique I should know about? There are plenty of pictures online if you google "rotary mp00712". Mine is a gold one but I don't expect that matters for this.

I'd be happy to take any specific photos if it helps. I love the watch and wind it every day, it would be nice if it would tell the time reliably too!

Thanks,

Stewart

 

[JohnR725]

40 minutes ago, DeepSet said:

pictures online if you google "rotary mp00712".

While that is a true statement that there are plenty of pictures online they are worthless for what we need. We need a picture centered above the balance wheel on the back side. Then another decent picture of just the entire movement on the back side.

[DeepSet]

[Nucejoe]

A clear picture of hairspring coil is needed, not even John can see this coil. its dark.

Moving regulator arm so to increase the active length of hairspring, slows the rate.

 

 

[DeepSet]

Thank you. I'll try to get a better picture. Just so that I'm aiming at the right area, can you confirm that I have got the parts correct?

[watchweasol]

Hi  Yes that's the regulator arm,  moving it to the right will speed it up, Effectivly shorten the spring, conversely moving it to the left lengthens the spring and slows it down. But be very careful when doing it and move in miniscule amounts.

[DeepSet]

Excellent, thank you!

I'll give it a try and let you know how I get on in a day or two.

I managed a slightly closer picture for reference 

[DeepSet]

Update: I have made a few adjustments over the last couple of days, resulting in the image as below. It turns out that both of the little silver arms move, I'm not sure if it matters where they are positioned, or whether it's just their position relative to each other, but it seems to keep fairly good time now. Running ever-so-slightly slow this morning so I know the range and need to make my tweaks smaller!

Thanks so much for your help.

[jdm]

2 hours ago, DeepSet said:

 It turns out that both of the little silver arms move, I'm not sure if it matters where they are positioned, or whether it's just their position relative to each other, but it seems to keep fairly good time now. 

The arm where the end of hairspring is adjusts the center of oscillation, as explained in this video by our Host Mark Lovick. For an accurate setting of that, as well of the rate, a timegrapher is needed. 

 

[DeepSet]

That's really interesting, thanks.

[AndyHull]

That looks like a "Tongji" or Chinese Standard movement.

https://en.wikipedia.org/wiki/Chinese_standard_movement

I suspect the coils on the balance are touching while it is running, or there is oil on the coils, or the movement simply needs servicing. 

Can you post a current picture of the balance at rest. i.e. after you adjusted it.

The good news is that the movement is very easy to find and to get spares for. The quality of the movement is variable though. Some versions are actually quite well built, and some are, well, not so good to put it politely.

Rotary used to only use Swiss movements, but their more recent offerings use movements from China, Japan and Switzerland.

I have a couple of watches with skeletonized Chinese standard movements and they are reasonable time keepers once cleaned and oiled, so you should be able to get it working acceptably well.

Edited March 11, 2021 by AndyHull

[AndyHull]

16 minutes ago, jdm said:

For an accurate setting of that, as well of the rate, a timegrapher is needed. 

You could use tg-timer from here -> https://tg.ciovil.li/

There are also a couple of phone apps that can do watch timing, but I haven't tried any of them.

I do however use tg-timer on my laptop, which is almost as good as a "proper" watch timegrapher.

 

[jdm]

7 minutes ago, AndyHull said:

You could use tg-timer from here -> https://tg.ciovil.li/

There are also a couple of phone apps that can do watch timing, but I haven't tried any of them.

I do however use tg-timer on my laptop, which is almost as good as a "proper" watch timegrapher.

Unfortunately, as most readers here know well, there is little chances of getting realiable results from a PC or mobile app without using a proper microphone. That should be told t9 beginners in order not to set wrong expectations. The thread below is about that exactly.

 

[DeepSet]

I think this is getting a bit beyond my capability (and aspirations)! 

I'll wait for the watch to run down and take another picture as requested, but I'm minded to carry on with the tiny tweaks until I get reasonable performance and if I don't manage it I'll look up somebody local to service it once things start opening up again. 

The internet is a wonderful place for help with anything and everything, I'm grateful for your advice. If any of you experts happen to live in the East Devon area and would do a service that might be of interest!

 

[AndyHull]

Quote

Unfortunately, as most readers here know well, there is little chances of getting realiable results from a PC or mobile app without using a proper microphone.

I agree completely.

I personally get away with using the built in microphone on my laptop or the one in my headset, however your mileage may vary.

You also need a very quiet environment, otherwise you will pick up spurious noise from your surroundings. This is why a good quality microphone in a sound proofed container is a very good idea.

This is one of the advantages of a "proper" time grapher. It includes the microphone and a clamp that lets you time the watch in different positions. They are probably also a little better at filtering out noise from their environment.

For hobby use though tg-timer has served me well.

 

Edited March 11, 2021 by AndyHull

[AndyHull]

3 minutes ago, DeepSet said:

I'll wait for the watch to run down and take another picture as requested, but I'm minded to carry on with the tiny tweaks until I get reasonable performance and if I don't manage it I'll look up somebody local to service it once things start opening up again. 

If you are careful, and take your time, there is a pretty good chance you will get it working.

[AndyHull]

By the way, "The basic specification of the Standard wristwatch caliber is a minimum of 17 jewels, 21,600 bph (beats per hour) escapement, a minimum 40-hour power reserve and an average rate within +/-30 seconds per day."

The ones I have perform better than this, but an average rate within +/-30 seconds per day is the figure to shoot for.

Edited March 11, 2021 by AndyHull