Regulating a bunch of watches (Miyota 8215 sucks)

[straps68]

I don't usually care how accurate my watches are, to me they are mostly jewelry. Rarely wear the same watch longer than a day at a time so I don't usually set the date. But the other day I decided to put a bunch of my watches on the Timegrapher.

First a 5 year (I think) old Steinhart pilot with an ETA 6497.1 inside. It runs really well with zero beat error in all positions and a nice amplitude. Very impressive!

My BVLGARI Diagono, which is almost 11 years old and has never had a service was running about 12 seconds slow so I decided to regulate it to about +1 seconds per day dial up and this was the result:

DSC_0592bb

The dial up and down difference is about 1 second. The other positions are great as well. Beat error varies by 0.1ms. I'd say the cal.220 is awesome quality and quite beautiful to look at as well.

I then tested two of my Seikos. First is a 10 year old Land Monster and as soon as I put it on the machine it became quite clear that that one time a friend of mine dropped it on the hardwood floor has made a difference. It runs quite poorly, the amplitude is low and variable and beat error varies between positons
The second Seiko is a 6309-7040 from 1984. I bought it on eBay from a user in the Phillipines who claimed the watch was serviced. If he meant that he poured some dirt and garbage into the movement then he was truthful but it still runs much better than the Land Monster.

I then tested a watch I have with a Miyota 8215 movement, a Barbos. I was going to take pictures but I was afraid that my camera would throw up so I did not. The beat error varies by about 4ms between positions and so the trace looks really terrible. And of course accuracy varies a lot between the positions as well. TBH I did not expect such terrible results. In the end the watch can be regulated to within a few seconds a day but it's best not to do it with a timing machine - it's just too sad to look at.

[unreformed66]

I've discovered that the regulator pins are too far apart in the vast majority of the Miyota movements. That's why you get the errors you mention. Let's face it, you can buy these movements brand new for under $50.00 so I don't expect ETA quality. They can be "fixed" to run better than they come from the factory but quite frankly I've never been impressed with them. That's why I won't pay the money for most of the microbrand watches even though some have very nice designs. They all use dime-a-dozen Miyota movements and I just don't see the value for the prices that some of them go for.

[Tanukjaju]

I’m glad that you guys are sharing this. I wonder how much it could cost for them to fix the design flaw. I doubt if the movements would cost much more. I think I’ve had a miyota once... but I cannibalized the case and sent the movement away.

[straps68]

I’m glad that you guys are sharing this. I wonder how much it could cost for them to fix the design flaw. I doubt if the movements would cost much more. I think I’ve had a miyota once... but I cannibalized the case and sent the movement away.

AFAIK they did "fix" the flaw. It is called the 9015 but I never had one in my hands so don't know from experience.

[straps68]

I regulated and timed a Seagull 2551 movement in one of my builds and found that it is a really nice one. Here are the numbers, which I think look very impressive:

Pos Rate Amp Beat error
DU -1 282 0.0
DD -2 274 0.1
3h +1 242 0.2
6h +1 245 0.0

I set the lift angle to 52 as I can't find any info as to what it actually is so amplitude numbers may be off. This movement is ~5 years old and has not been serviced. The 2555/2551 costs about the same as Miyota 8215 and I'd say based on my experience that they are a lot better.