This is a report I got after a Seamaster service. Any info on the abbreviations etc. would be much appreciated.

 

CH = dial up
CB = dial down (I thought this was FH?)
3H = crown up (3:00 pointing up, watch straight up & down)
6H = crown left
9H = crown down
12H = crown right

X =
D = largest difference (yours is between 6H and CB)
DVH =
Di =

I'll try to find the rest and fill it in.

 

Thanks, so it refers to the physical positioning of the watch... makes sense

 

What Seamaster is this? I don't know of any that use 52 degrees for lift angle, so that is an incorrect setting on the machine for your watch. Not super important, but still it should be correct IMO.

Anyway I'll explain the more important numbers for you in a bit of detail...

As Dennis has stated the individual readings are for the 6 different positions the watch is checked in - Chronometer testing leaves out the Crown right position, so they have added that in and I do the same. The rates are in the leftr column expressed in s/ds, the beat error is in the middle expressed s MS, and the balance amplitudes are on the right column expressed in degrees of rotation.

Now for the important things below the horizontal line - this is where the machine calculates averages and deviations.

D is the Delta, and that is (to the watchmaker) the most important number provided that things like balance amplitude and beat error are within normal parameters, and in this case they are. The Delta is the difference between the fastest and slowest position, and this will tell you how much the rates will vary as the watch is stored in different positions.

Your is a little over 8 seconds, and that is well within Omega specs - for most modern chronometer movements they allow as much as 12 seconds a full wind, and up to 15 seconds at full wind -24 hours.

X is the average of all 6 positions and is +0.4 s/d. Although this seems very good, Omega usually calls for a target rate of +3, because people do not like watches that run slow. Given that you have one position at -4 s/d, it's possible the watch could end up slow if the watch spends a lot of time in that position.

The act of regulating is moving that average number, but it will not change the Delta. To affect the Delta, you have to perform adjustments, which are different than simple regulation.

Hope this helps.

Cheers, Al

 

That's fascinating stuff, thanks. I never really considered variations in position when I was initially looking at it.
The Seamaster is an old Bond, from 1999 - actually, the one in my avatar. I asked the retailer to check as I was finding it running at about 12s fast a day, so they took it back and said they'd made adjustments, and provided this report. Seems it should be a little more accurate now.

 

And now if it continues to run fast, you know to leave it over night in the dial down position, and that will help to slow it down overnight.