So, I've had my Twelve Ti since late June. It arrived with a mis-aligned bezel, went back for rectification and suffered minor cosmetic damage during the process. CW customer services have made a goodwill gesture for the inconvenience and are going to re-case the watch when new cases are available. Not ideal, but I'm ok with it.

I've been using it as my daily for the last three weeks or so, the case is still looking spot on and it's become my favorite watch. However, where it was initially keeping excellent time (gaining about 0.7 seconds a day and losing the right amount to correct this if left crown up overnight), it is now running slow, losing 35 second over 3 days. No idea what's changed, the watch hasn't been subjected to any knocks, magnetic fields, high or low temperatures. Strange stuff!

This watch seems to be cursed. It's knocking my confidence in the brand to the point where I'm seriously considering cancelling my outstanding orders. Just unlucky, or is this par for the course?

Sorry to hear about your issues with your Twelve Ti.

How do you know that your watch has not been near any magnetic fields? They are practically everywhere nowadays, especially if you have a mobile phone, ipad/tablet, laptop, or even a fridge. Usually, the most common cause of a watch suddenly changing its timekeeping is because it's become magnetised. I would suggest you try de-magnetising it first to see if that helps. De-magnetisers can be bought pretty cheaply on Amazon if you don't have one already.

Hope that helps.

Have you kept it fully wound over the three days, accuracy will often drop if a watch is only partially wound?

Guy

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welshlad wrote: ↑Sun Jul 30, 2023 12:53 pm Sorry to hear about your issues with your Twelve Ti.

How do you know that your watch has not been near any magnetic fields? They are practically everywhere nowadays, especially if you have a mobile phone, ipad/tablet, laptop, or even a fridge. Usually, the most common cause of a watch suddenly changing its timekeeping is because it's become magnetised. I would suggest you try de-magnetising it first to see if that helps. De-magnetisers can be bought pretty cheaply on Amazon if you don't have one already.

Hope that helps.

I'll try it, but I thought magnetisation usually makes them run fast by effectively increasing tension in the balance spring? I haven't been anywhere on Wednesday that would produce any sort of exceptional field. I'm always careful to keep watches well away from the speakers and headphones. The accuracy took a nosedive some time Wednesday night.

The watch had a 1.4ms beat error from day one, but I didn't worry too much as it kept excellent time. I'm not sure if that signifies any sort of issue?

Bahnstormer_vRS wrote: ↑Sun Jul 30, 2023 1:44 pm Have you kept it fully wound over the three days, accuracy will often drop if a watch is only partially wound?

Guy

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Yes, when it started to slow, I wound it with a top up, but it made no difference over Thursday, so I fully wound it and it still made no difference. I've usually got a pretty good handle on how each mechanism behaves and I generally don't need to reset a watch once it's done once and in use. This one was great, needing a top up every other day to stay within a second of NPL, then big change.

I've been letting it run down to see if that improved things, but it seems to be getting worse rather than better as it runs down. I'll let it run fully down and then give it a full wind and see how it goes, but I can see another trip to it's maker being required.

^^^^ Thanks for your response and feedback, Chris.

You've clearly got a good handle on what makes these things tick and it must be frustrating for you.

I had an initial thought that -35 sec over three days is <12 sec/day and within -20/+20 sec/day BUT then realised that the Twelver TI has a COSC movement and should be doing better.

Do please, as Steve @welshlad suggested take a look at the Magnetism issue; it might surprise us all, but will at least eliminate this as a potential issue.

Good luck.

Guy

Bahnstormer_vRS wrote: ↑Sun Jul 30, 2023 4:13 pm Do please, as Steve @welshlad suggested take a look at the Magnetism issue; it might surprise us all, but will at least eliminate this as a potential issue.

Yes, as Guy says, it's an easy thing to try, so is worth a shot. I've seen examples of magnetism both speeding up and slowing down watches, so you never know. I've also heard of watches getting magnetised off the magnetic seal on a fridge, being too close to a laptop, e.g. from typing, resting one on an iPad where the case had a built-in magnet to signal to turn it on/off when the case was opened/closed, etc. Danger lurks everywhere!

Good luck.

I'll buy a demagnetiser and give it a go. Any suggestions for a decent one?

This is the one I bought from Cousins a couple of years ago;- Etic 340.400 although it appears to have been discontinued, but is instead available from H S Walsh

However, there are also a plethora of similar looking ones on Amazon, albeit I'd try to avoid cheap / low quality ones.

Guy

Chris GB wrote: ↑Sun Jul 30, 2023 2:24 pm
The watch had a 1.4ms beat error from day one…

That’s not right. A new chronometer should have been adjusted to give a much better figure than this. I’m not happy if I cannot regulate to .2ms.

MarkingTime wrote: ↑Sat Aug 26, 2023 11:03 am

Chris GB wrote: ↑Sun Jul 30, 2023 2:24 pm
The watch had a 1.4ms beat error from day one…

That’s not right. A new chronometer should have been adjusted to give a much better figure than this. I’m not happy if I cannot regulate to .2ms.

I'm wondering if the movement was regulated with a bit of dust in the balance spring and this has become dislodged. The beat error is now significantly better, although still quite variable at between 0 and 0.6ms. Amplitude seems a bit on the low side for such a new movement too at between 275 and 235 degrees. Position dependent, accuracy measures between -2 and -10 seconds a day, but averaging across the same positions as it's certificate, it is -7s per day which is pretty much what I see when wearing it. Not impressive for a so called chronometer. I'll ask them to re regulate and certificate when it is re cased. Probably cheaper and easier for CW to just replace it!

With a new movement, I'd expect to see around 300º amplitude, I've seen more than that on a 30 year old ETA2892 chronometer.
Amplitude variation of less than 20º dial up/dial down and less than 40º between pendant horizontal and vertical.

I'd say this shows a lack of quality control.

Chris GB wrote: ↑Sat Aug 26, 2023 4:13 pm

MarkingTime wrote: ↑Sat Aug 26, 2023 11:03 am

Chris GB wrote: ↑Sun Jul 30, 2023 2:24 pm
The watch had a 1.4ms beat error from day one…

That’s not right. A new chronometer should have been adjusted to give a much better figure than this. I’m not happy if I cannot regulate to .2ms.

I'm wondering if the movement was regulated with a bit of dust in the balance spring and this has become dislodged. The beat error is now significantly better, although still quite variable at between 0 and 0.6ms. Amplitude seems a bit on the low side for such a new movement too at between 275 and 235 degrees. Position dependent, accuracy measures between -2 and -10 seconds a day, but averaging across the same positions as it's certificate, it is -7s per day which is pretty much what I see when wearing it. Not impressive for a so called chronometer. I'll ask them to re regulate and certificate when it is re cased. Probably cheaper and easier for CW to just replace it!

I’ve just checked mine on the Timegrapher and it sounds like there’s definitely an issue with your movement.


Results face up.

Results crown up.

Mine has averaged -1.2 seconds per day over the three months I’ve had it.

It is interesting that the beat error became hugely better at the same time as it started running slow. Previously, it was running average of +0.7s/d in general wear. Here are a couple of screenshots of it after stabilisation time, around an hour after winding fully.

So this is as good as it gets, face up:

This is more typical crown up:

EDIT: Here's my C63 Sealander for comparison:

The watch needs to go back for a service. No question.

I'd expect those figures for a regularly used watch of several years of use (5+) that had never been serviced. Still, not horrendous, but not right either

Chris GB wrote: I'll ask them to re regulate and certificate when it is re cased. Probably cheaper and easier for CW to just replace it!

It is worth remembering that the COSC certification is carried out on the movement before being fitted into a watch.

If CW are to regulate your watch for you, which they are perfectly capable of doing, they will not be in a position to get it recertified.

Ultimately, if you are not happy with it, raise a Repair Request via CW's website and get it checked out.

Guy

PS> apologies if the 'return to CW' part of the discussion has been covered already.

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