The Master Co-Axial has 15,000 Gauss and the 8508 has not Master Co-Axial on the dial but has also 15,000 Gauss.

I know that the Master Co-Axial has an accuracy of 0/ +5 sec/day and the other Omega movements does have an accuracy of -1/ +6 sec/day, according to Omega standards.

Are there more differences between an not Master Co-Axial 15,000 Gauss and a Master Co-Axial? Or am I wrong in my conclusion that the 15,000 Gauss is not a Master Co-Axial because it not says Master on the dial?

Kind regards,
Arno

 

Timing specs for all Omega COSC watches are still the same - all are -1 to +6 average daily rate...they may change in the future, but not yet in any documentation I have seen.

Cheers, Al

 

Hi Ash - yes I'm aware of the METAS. What I am saying is that none of the actual timing tolerances Omega publishes for watchmakers to work towards have been changed yet. In other words, Work Instruction 28 has not been changed yet, so all the tolerances for these watches are all still -1 to +6. There are no "METAS certified" watches with different tolerances at this time.

Cheers, Al

 

The Master Co-Axial Seamaster watches are delivered without the chronometer certificate that came with the older versions.

Could it be that these watches are already tested to METAS standard but by Omega and not METAS while the agreement with METAS came into fruition only later? Does it take until mid 2015 to design a new "credit card" certificate?

 

Just found this link: http://forums.timezone.com/index.php?t=tree&goto=6994149&rid=12189#msg_6994149

To clarify, once an Omega calibre is COSC-certified, it then qualifies for the Master Chronometer testing by METAS (Swiss Federal Institute of Metrology). In addition to measuring the performance of the watch in daily wearing conditions, METAS tests that the watch functions properly when exposed to strong magnetic fields of 15,000 gauss. Altogether, METAS measures eight criteria: 1 The function of the movement during exposure to a magnetic field of 15,000 gauss; 2 The deviation of the running time of the watch in six positions; 3 The deviation of the running time of the watch between 0 and 2/3 power reserve; 4 The function of the watch during exposure to a magnetic field of 15,000 gauss; 5 The deviation of the average daily precision of the watch after exposure to a magnetic field of 15,000 gauss; 6 The average daily precision of the watch in tests replicating daily wearing conditions (six positions, two temperatures); 7 The power reserve of the watch (autonomy functioning without winding); and 8 The water resistance of the watch (tested in water).

But it nothing says something about accuracy.

Kind regards,
Arno

 

So, as yet, the Aqua Terra is not available with this certification?

 

My Omega De Ville 8500 has an accuracy of -1 sec/week, and I have read that this is about the regular average for this Omega 8500 movement. It oly depents how the watch is put to rest, my watch an most of them need to be positioned overnight with the crown up. I am very confident with this result. You can find these movements in all the Omega series, even with the anti magnetic master movement. Some of the sea Masters do have the 8400 movement, which is also a Master movement and released later than the 8500 series. Good luck to you all.

Kind regards,
Arno

 

I now have data on the timing specs...they measure isochronism differently for the METAS specs than they do for COSC, so until I have time to look at it in more detail I can't say if it's a looser or tighter standard than for the COSC watches. As noted the average rate specification is 0 to +5 for the METAS instead of -1 to +6 for the COSC, but the delta at full wind is exactly the same, so 12 seconds of delta measured over 5 positions is still allowed.

So from what I can see now, this is just tighter regulation, rather than better adjusting...

 

I could be wrong but with the older 8500 when it has a service will it be upgraded to be the same as a new omega 8500 sold. so will it be as anti magnetic as a Master Co - Axial?

 

I wouldn't bet any money on that happening. In fact, Omega is probably betting that you'd be willing to buy a new watch that has the latest anti-magnetic properties

addendum:

Omega probably has buckets of non-anti-magnetic replacement parts for the older 8500s that can be used for repairs & servicing.

 

The Master Co-axial is not METAS certified. It should read Master Chronometer on the dial in that case.
8508 / >15,000 Gauss was just the first marking to be used. It corresponds to 8500 Master Co-axial, basically.

 

^He's right

 

The update from regular 8500 up to master will not be done because it simply won't fit. The service cycle for the 8500 is set on a generous 6-8 year, so in about 6 years my watch will have my first service. I do have changed my leather strap because these do have a lifetime of about 2 years, a metal would last longer but is much more expensive (too expensive for me at 1500 Euro). The wrist accuracy of my regular 8500 is going down from -1 sec/week to -6 sec/week after 2 years. On the timegrapher my watch shows a +2 sec/day rate (after 24h rest with crown and dial up), so nothing to complain about.

 

Dimensions of parts do not change...

 

I do have a regular 8500(B) but I realy think that my watch meets the 0/ +5 sec/day precision (on the timegrapher), but not the antimagnetic part of 15000 Gauss master. I am serius wandering what magnetic resistance level my 8500 (Si14) watch does have, it has a silicon spring and I believe it could match far above 1000 Gauss. Half way master would be nice.

 

Last weekend I have found an 850 Gauss magnet and with that magnet my watch stopped running easy, so it is for sure that the magnetic resistance of the 8500 (Si14) is much less than 1000 Gauss, I think it will be only a few hundred Gausss

 

So after exposing your watch to the magnet, it stopped running completely?