I have just purchased my first Omega, a 1964 Seamster De Ville, stainless case with rare Silver linen face, in immaculate almost new condition. Very pleased so far.

This watch is fitted with the slimline Cal 711 automatic movement. Just wondering what daily accuracy/variation can be reasonably expected from this movement? At at what point should I consider having it adjusted?

My first half a day of wearing it has seen about a +10 second advance. Will be interesting to check in the morning again after not wearing it.

 

Get your watch serviced by a good watchmaker before any damage is done internally. Despite many sellers claiming a watch has been serviced, most have not.

 

My newly purchased Omega has been running fast, but quite consistently - around 25 seconds per day.
I opened up the back, and using the Kello iPhone app, adjusted it as closely as possible to zero.
Kello is a great app, you place your watch against the microphone, it listens to the ticking, automatically
calculates beat rate, and then after analysing the signal for about 30 seconds, it tells you daily watch error in +/- seconds per day.

Results after initial ajustment have been outstanding, and the Cal711 movement is keeping exceptionally good time. Variation per day so far:
Day 1: +3 Seconds
Day 2: 0 Seconds
Day 3: 0 seconds
Day 4: -2 seconds
Day 5: -0.5 seconds.
Gotta say, thats pretty good for a 45 year old movement!!! Judging by this, I'll probably end up with less than 20 seconds per month of error!

It tends to gain about 1-2 seconds overnight when not worn, but loses that same amount during the day when worn.

I can now understand why the Cal711 was used as a basis for the 712 chrono certified movement. (however I have not tried extremes of temparature and
positions!)