5711 Miyota 9015 with 21J modified hands ... is time keeping accurate?

[Shiroutsuri]

I have been wearing the 5711 blue dial Miyota 9015 with modified 21J hands for 5 months now and the time keeping is running slightly fast at around 1 min each day since the first day! I have a few other Miyota 9015 watches and I must say they keep very accurate time but these are watches without any modification. This pigue my curiosity and I'm puzzled by this phenomenon!

I am just wondering whether this inaccuracy is due to the modification carried out to the hands or whether its because of an odd case of getting a poor 9015 escarpment movement. I have also asked my watch smith if he can adjust the accuracy but it seems that the margin of error is too small to rectify for the watch. Therefore, I would appreciate any constructive feedback from the learned forum members who have undergone the 21J hand modification to comment with regards to the time keeping accuracy. TQ

 

[ShiroTenshi]

I think 1 min can be regulated? Unless the regulating pin already reached the end. Take a clear pic of the movement with the balance clearly in sight and i will tell you.

Another possibility is that the balance spring is magnetized. In that case just get a de-magnetizer and de-magnetize it, but you need to regulate the movement after that.

 

[Shiroutsuri]

Thanks for your reply ST, just wanted to find out from others who have carried out the hands mod from the original Miyota hands to the 21J hands will cause the time to run fast.

 

[d4m.test]

From what I read the Myota 9015 can be regulated to +15 secs per day so as 1 minute is really a bit fast, the watchsmith should give it a try.

 

[FlawedRobot]

The movement can be made to run much tighter than ±15 secs/day.

 

[Shiroutsuri]

The watchsmith has taken it down to +16 secs/day and says its the best he can do. Any suggestions?

 

[d4m.test]

May not be relevant. But just sharing. I got the same problem last time but it was because my watch was magnetized.

 

[ShiroTenshi]

The watchsmith has taken it down to +16 secs/day and says its the best he can do. Any suggestions?

That is totally alright, just leave it as that.