Amplitude is good (assuming the timegrapher has the software necessary to read co-axial movements). Beat error is good.
Average rate of +8.0 seconds per day is not acceptable for a freshly serviced 8500. The delta is good (difference between the slowest and fastest positions--6.2 seconds) so there's no reason they can't slow that down. They should easily get that between 0 and +6 seconds per day. That's just sloppy work. The time it takes to adjust the timing is minimal.
If my Omega certified watchmaker had that I would tell him to get it around +1 to +3 seconds a day and he'd do it no problem. The movement is definitely capable of it.
When you say UK boutique, I assume you mean Omega boutique? Just making sure an Omega certified watchmaker did the work and not some slappy off the street.
I had the impression that the standard was 0 to +5s/day average, in which case the +8.0s/day would be out of spec. I don't know if there is a specification for maximum variation, for comparison with your 6.2s value. The variation doesn't look bad to me at first glance, but given that fact, it would have been nice for them to slow the rate down a bit for you.
Thanks for the response. I paid an Omega boutique UK for the service and I understand the work was done in their service centre in Southampton. So in summary, this couldn’t have been more official. You comment that the watch maker ought to have done better but do I have cause for complaint or is this within spec for a chronometer watch? I don’t want to complain, I just want to be sure that it is all done right and it’s as it should be. With the case back coming off after receiving the watch back and omega showing little (no) interest in explaining why, I’m a little concerned it’s sub-standard. If this doesn’t meet their accuracy spec after a service and they still shipped it, then clearly they’ve paid no attention to anything!
You have cause for complaint. They literally gave you proof that the watch is not within spec. Spec is no more than +6 seconds a day. Their timegrapher report shows it at +8 (averaged across all positions). It's not a huge deviation but it's not acceptable.
You're probably not an NFL football fan but it reminds me of a saying by Mike Tomlin, head coach of the Pittsburgh Steelers: "The standard is the standard."
And in this case Omega did not meet their standard and then gave you the evidence.
I'm also shocked they would give you back a watch with a loose caseback. That demonstrates a shocking lack of competence and quality control.
