Power reserve on watches

[Tmuir]

I just restored a Seiko 7006a which I also replaced the mainspring on.

The technical specifications states the watch has a 43 hour power reserve.

I don't have an automatic winding machine so whilst watching TV for an hour or so I held the watch and shook it backwards and forwards to wind it up. I then sat it down and it ran for about 52 hours. As I did not write down the time I stopped winding it I just figured I had remembered the time incorrectly so repeated the process. It has now just passed the 45 hour mark and is still going strong.

I know the stated power reserve will not be exact to the minute, but on average how close would you expect it to be?

Yes I did install the correct mainspring for the watch and I did use braking grease on the barrel wall. I didn't use the Seiko grease as I don't have any, instead I used Moebius 8217.

Could it just be that the Moebius grease is a bit more 'sticky' than the Seiko grease allowing it to wind up more before slipping?

Or after the grease has been more evenly spread around the barrel from slipping a few times it wont grip so much and will reduce the power reserve?

[jdm]

8 minutes ago, Tmuir said:

Or after the grease has been more evenly spread around the barrel from slipping a few times it wont grip so much and will reduce the power reserve?

That certainly doesn't seem to be happening in your case, because the watch is running longer than supposed, not less.

However what you want to pay attention to is how it runs (isochronism), especially during the last hours. Normally when you let a watch to almost wind down, the timekeeping becomes so poor that you will have to reset it. 

[Tmuir]

Up to 43 hours it was looking pretty good time wise. I had set it in beat with 0.0ms error withto -2 to -4 seconds a day dial up which is how it has been sitting for the last 2 days, will be interesting to see how it looks in another 3 hours

[jdm]

Maybe the replaced MS is a bit longer.

[Chopin]

1 hour ago, jdm said:

Maybe the replaced MS is a bit longer.

This is what I'm thinking... From what I've noticed on my vintage watches at least, some would "run" for a few hours longer than the declared power reserve of the movement.