power reserve on 3 black bays on winder

[ProfGlenn]

Hi. Because of an electrical problem I switched all my winders off. I had three black bays on one winder (red, black and bronze - all in-house movement).

I stopped the winders on Saturday afternoon. Now I have always suspected, because the accuracy on the Bronze drops off after about a week or so on the winder to -2s/day whereas on the wrist it is more like -0.5 or less, that the winder is not keeping the bronze fully charged. Anyway, I wore the bronze for about 5 hours on Saturday evening. I then didn't wear it again until Sunday late afternoon for about 6 hours. Tonight I noticed the bronze had stopped. At 12:30 which I presume was midday today. During that time the red bezel was still running (so wore that today) and the black is STILL running well over 48 hours after the winder stopped. The red and black maintain good accuracy on the winder- an indication they are maintaining charge. So this is the first time I have ever been forced to test my theory that the bronze is not maintaining as much charge on the winder as the other two. They have the same movement - so how can this be??

I have seen a similar phenomenon on 4 watches with selitta movements - 2 in a similar case to each other have a much higher power reserve after coming off the winder than two other watches with similar cases (but different to the other two) with the same movement.

So, I think i have proven why my Bronze accuracy drops off eventually on the winder - it must be only just keeping it charged. How many hours not he wrist would it need to get from zero power to full power? And why would the bronze not charge up as well as the other two on the same winder? Why would the weight of the case or the dial matter, for example? Is it s fault? A sticky rotor? I don't think it is simply because of the similar experience with the Selitta movements.....

Anyone got any ideas please?

Thanks
Glenn

[imperio]

What is your question? Why don't you manually wind your watches?

[ProfGlenn]

The question is why a winder is enough to keep two watches holding much more charge than a third watch with the same movement. I keep them on winders to avoid manual winding as automatics are not meant to hand wound very often.

[imperio]

Originally Posted by ProfGlenn

The question is why a winder is enough to keep two watches holding much more charge than a third watch with the same movement. I keep them on winders to avoid manual winding as automatics are not meant to hand wound very often.

I do not have the answer to your question but you just made my day.

[ProfGlenn]

Thanks anyway! So the black bays have MT5602 movement and the bronze has 5601. Anyone know if there is ANY difference?

[ProfGlenn]

ah-ha.....5602 is 31.8mm diameter. 5601 is 33.8mm.

So the rotor is larger, it seems. Interesting.....

[Phrank]

Originally Posted by imperio

I do not have the answer to your question but you just made my day.