I have a C60 GMT 600 Trident dated August 2021 that has been worn infrequently due to many other watches.

I wore it the other day and was surprised to see it was +40 secs/day out.

Should as take this as normal given it’s age, or given it is in the 60 month warranty period ask for it to be returned to CW for regulation?

I know the spec on the watch is +/- 20 secs/d, but it is now operating twice that.

Just wanted to know of others experiences and whether the request is reasonable.

Firstly, check that it hasn’t been magnetised.

If you’re happy that it isn’t, try keeping it running for a week. Watches often run poorly after a long layoff then resume a more normal service as things loosen up.

tikkathree wrote:

Amor Vincit Omnia wrote: ↑Sat Apr 19, 2025 7:26 pm Firstly, check that it hasn’t been magnetised.

If you’re happy that it isn’t, try keeping it running for a week. Watches often run poorly after a long layoff then resume a more normal service as things loosen up.

Exactly this ^^^^^. The swing to running significantly fast rather than just a bit fast made me wonder about magnetisation too..

It sits in the same box and gets the same worldly treatment as my Dartmouth, Super Compressor and Submariner. They are the same age except the Submariner, which is a decade older. All three run around +/- 2 secs/d, so if it is magnetisation, it is very selective towards the Trident GMT.

Sent from my SM-X610 using Tapatalk

As already suggested; check for magnetisation and run it, fully wound (normal daily wear should suffice, no need to hand wind) for a week or so.

Check again and let us know how you get on.

Guy

Sent from my Galaxy S23 Ultra using Tapatalk

Bahnstormer_vRS wrote:As already suggested; check for magnetisation and run it, fully wound (normal daily wear should suffice, no need to hand wind) for a week or so.

Check again and let us know how you get on.

Guy

Sent from my Galaxy S23 Ultra using Tapatalk

Thanks for the response. I will give it a full week on the wrist and report back. Off to YouTube to investigate magnetisation.

There have been times I have accidentally set the time 5 seconds ahead or even a minute or 5 minutes ahead. Shoot, even an hour ahead once. Strange things can happen. I think it wise to wear it for a week and track the time to make sure you know what you’re dealing with. Best of luck and report back!

My C9 Moonphase has a specified timing tolerance of +20/-10 sec/day. After some years of use mine was out of spec, running at -20 sec/day. When I sent it to CW for a service I asked that it be regulated. When I got it back it was running at +20 sec/day! Technically in spec but not really the result I was hoping for, especially given the cost.

I downloaded a free magnet meter app from the App Store. Tested it on a couple of things I knew were magnetic and it recorded high magnetism, so the app seems to work.

Passed the watch in question over the phone (top left corner) and got a peak reading of 80 micro-Tesla (uT), which is magnetism ‘slight detection’.

Anything under 60 uT is classified as magnetism ‘not detected’

Then I put a watch that is running to COSC specs, and it was running at 40 uT and magnetism ‘not detected’.

Tested on an Android app and got similar results.

So, it does appear I have magnetisation on the watch that is running fast.

So, I did a bit of research on line and obviously demagnetisers are the way to go. By placing the watch in/close to an AC generated magnetic field eliminates the any stored magnetism.

But not having demagnetiser to hand, I found genuine online recommendations to hold the watch close to an operating AC motor in a plastic case (corded drill, fan etc.) and move the watch in an arc. Sceptical about this, I gave it a go.

Voila, it worked!

Timed the watch over the next 24 hours and it was back well within normal tolerance for a Sellita movement as advised by CW.

Well pleased

nowttolose wrote: ↑Wed Apr 23, 2025 8:53 pm So, I did a bit of research on line and obviously demagnetisers are the way to go. By placing the watch in/close to an AC generated magnetic field eliminates the any stored magnetism.

But not having demagnetiser to hand, I found genuine online recommendations to hold the watch close to an operating AC motor in a plastic case (corded drill, fan etc.) and move the watch in an arc. Sceptical about this, I gave it a go.

Voila, it worked!

Timed the watch over the next 24 hours and it was back well within normal tolerance for a Sellita movement as advised by CW.

Well pleased

Any varying magnetic field will do!

Any thoughts of electricity being total witchcraft have completely evaporated

It is called electrickery for a reason.

As a final update, as mentioned in the opening post the watch was running +40 sec/d. After placing close to an AC motor of a household appliance it reduced to +15 sec/d.

Just had the watch demagnetised with a proper device and it is now running around +3 to +4 sec/d.