Open a Tag Heuer Aquaracer 300 case back

[LazyTimegrapher]

1 hour ago, VWatchie said:

As repairers and enthusiasts, we always want to see the movement or we simply want to figure it out well in advance of the inevitable service that will happen sometime in the future! 

Well, I felt like a Master Watchmaker and owner of the world! Seriously! Then after six months or so I slowly started to realize I had only scratched the surface. After another six months, I knew for sure I had only scratched the surface. Nevertheless, working on watches is a wonderful way to waste your time! 

That’s helpful to know. Watchmaking does seem like a bottomless abyss of knowledge. I’m not sure I agree that it’s a waste of time, but it’ certainly seems like a fun thing to learn how to do. As you see from my other post, I have a pretty ambitious vision for this watch.  Whether I’ll ever be capable of realizing it is another question. Either way, I don’t think it can’t hurt to try (very slowly and carefully that is).

[LazyTimegrapher]

Do posts always have to be approved or is there some qualification or something after which approval isn’t required?

[LazyTimegrapher]

As it turns out that other article was in fact correct. See the attached images. When I removed the metal ring, I found six screws in the groove below them.

 

I suppose that concludes the mystery of how to open this watch.

 

I’ve decided (for now) to heed the advice of my wife and those of you here who say it’s a bad idea to open this brand new watch and mess with it given that I have no experience repairing watches.

 

I suppose the final question I have for you all is what process should I undertake to gain the skills required to have confidence to work on this aquaracer. The first thing I wanted to do with this watch was attempt to regulate it and slow it down a bit. However, I also have ambitions of swapping out what I suspect is a standard grade SW200-1 with a top grade version. I also think it’d be really cool to figure out how to give this watch a display case back.

 

What things should I make sure to do first before graduating and allowing myself to tinker with this aquaracer?

 

Thanks again for everyone’s help!

[RichardHarris123]

Your first few posts need approving, not sure of the number after that no approval needed. 

[tomh207]

The easiest way to tell what grade the movement is by inspecting it with special reference to the balance. Standard and elabore as a pair share the same balance which has different shaped spokes compared to the ones used in top and chronometer. It could be standard, elabore or top, unlikely to be chronometer grade as that is often marked on the dial. 
 

Tom

[VWatchie]

12 hours ago, LazyTimegrapher said:

I’m not sure I agree that it’s a waste of time

I didn't mean that literally but you could of course not know that. I was thinking of Jerry Seinfeld who recently said: "The secret of life is to waste time in ways that you like".

12 hours ago, LazyTimegrapher said:

I'm not sure  where I read it, but I do believe I read that they used the lowest grade. I could be wrong though, so if anyone finds better information on the movement, let me know.

If true, it is shameful considering the price. I do not think it is true. On the contrary, I think they are using Sellita's premium grade but it would be interesting to have it confirmed or denied by a reliable source.

12 hours ago, LazyTimegrapher said:

I really like the Tag Heuer aquaracer

So do I 

Edited June 18, 2024 by VWatchie

[LazyTimegrapher]

I probably will open the watch eventually and when I do I’ll post pictures of the movement. It should be possible to figure out what grade it is once I’m able to take a look at it.

 

Given the positional variation and the daily rates I’m seeing at full wind, it’s hard to believe it’s a top grade movement though. I’ve seen others talk about SW200-1 movements claiming very high accuracies that are often significantly better than COSC standards.

[tomh207]

Considering that at a base level the difference between the top grade and chronometer grade is just one has gone through the chronometer certification process and the other hasn’t. So would be easily capable of chronometer like performance 

 

Tom

[eccentric59]

18 hours ago, LazyTimegrapher said:

What things should I make sure to do first before graduating and allowing myself to tinker with this aquaracer?

 

Get a decent set of basic tools. Read books about watchmaking, watch videos, or better yet, take Mark's courses.

Ruin your first movement, service your second and repair your third. By that time, you should know enough to know what you don't know and what you're not comfortable doing. 

[LazyTimegrapher]

4 hours ago, eccentric59 said:

Ruin your first movement, service your second and repair your third. By that time, you should know enough to know what you don't know and what you're not comfortable doing. 

Wise words of advice. That sounds like a reasonable plan. Thanks.

I do plan to take the watch fix courses. Probably at least the first three. I’m not really a chronograph person but level 4 does sound interesting whenever it’s ready.

[LazyTimegrapher]

I did a little research online in forums and it looks like the Caliber 5 is a standard grade movement. 
 

see pictures in this thread 

https://www.watchuseek.com/threads/can-you-help-me-about-the-grade-of-tag-heuer-calibre-5-movement-grade.4911629/

And also on caliber corner

https://calibercorner.com/tag-heuer-caliber-5/

None of the images appear to have a glucydur balance wheel. At least as shown in this thread 

 

https://www.watchuseek.com/threads/luxury-and-normal-watches-using-same-movement.1934121/page-8

 

whenever I open my aquaracer I’ll post an image of the movement and balance wheel. However just given that it’s daily rate ranges from +4 to +20 in different positions (see my earlier post for all the different positional rates) it makes sense that it is a standard grade. 

it’ll be a fun project to eventually swap the movement with a top grade sw200

[VWatchie]

2 hours ago, LazyTimegrapher said:

I did a little research online in forums and it looks like the Caliber 5 is a standard grade movement. 

Interesting! It may be just as you say but I think we can be pretty sure that Tag Heuer doesn't just throw the movement in without first ensuring that everything is working properly. I expect their quality control to be rigorous. Anything else could lead to disaster as long as they wish to be able to charge as well as they do.

[Logichara]

If the typical screw-down method isn't working and there are no visible screws under the bezel, it might use a different mechanism like a snap-on case back. Have you considered using a case knife or a case back removal tool designed for snap-on backs?

[LazyTimegrapher]

I haven’t opened the watch yet, but I did find the screws under the bezel spring. I tried to show the screws in the images above. I just haven’t worked up the courage to open the watch yet.

[Logichara]

On 6/24/2024 at 10:56 PM, Logichara said:

If the typical screw-down method isn't working and there are no visible screws under the bezel, it might use a different mechanism like a snap-on case back. Have you considered using a case knife or a case back removal tool designed for snap-on backs?

It's also worth double-checking the Tag Heuer manual or contacting their customer service for detailed instructions tailored to this specific model. Also, I recently stumbled upon some <edited to remove link to external site for fake watches >
that are remarkably close to the originals. It's fascinating how they achieve such authenticity without the high price tag. It really makes you rethink traditional luxury watch purchases.

Edited July 2, 2024 by tomh207
Removed link to fake watch sales

[montrebella]

On 6/24/2024 at 5:56 PM, Logichara said:

If the typical screw-down method isn't working and there are no visible screws under the bezel, it might use a different mechanism like a snap-on case back. Have you considered using a case knife or a case back removal tool designed for snap-on backs?

Did you read the other posts and look at the pics, this is NOT a snap-on case back, using a knife or tool for snap-ons will cause great irreversible damage ! The screws under the bezel click [which some incorrectly labeled as the bezel spring] hold the caseback and need to be removed first, Seiko MM models use similar set-up, it's elaborate but not unusual...

[LazyTimegrapher]

As I mentioned in some of my prior posts, I would probably work up the nerve to open the watch eventually. Well, this morning I woke up and decided to give it a go.

In the intervening time, I bought a set of 10 watch screwdrivers, 5 brass pliers, a watch case vise/holder, and 4 loupes. They were all quite affordable around $10-20 for each set of tools. My wife had already bought me a time grapher some time ago, so I watched some YouTube videos on how to regulate an SW-200-1 and decided to try my luck opening the watch and turning the fine regulation screw a bit.

The following posts will break down the steps of what I did.

The image below shows the set of tools I used for the job.

Here’s the watch in question. The images show the watch exterior front and back. The last one shows the dive bezel and the bezel spring removed, which reveals the six screws under the bezel holding the case back on. This is as far as I got during my last aborted attempt to open the watch.

 

The next step was to remove the six screws under the dive bezel and spring that hold the case back on.

 

At this point I thought I needed to unscrew the case back, so I put the watch in the vise and used the rubber ball method to try to unscrew the case back. I applied as much force as I could by hand, but it wouldn’t move the slightest bit. This left me quite confused, so I took the watch out of the vice and inspected it. As I was rotating the watch around and looking at it, the case back came loose and nearly fell off.

 

Apparently those six screws are the only thing holding the case back on, so once they are removed, it comes off very easily.

 

Then I inspected the movement. Tag Heuer calls this movement the Caliber 5 and gives very little information about it beyond that. However, through research on the internet, I surmised it was almost certainly a Sellita SW200-1. My suspicions were confirmed upon review of the movement.

In the second picture below, you can see SW200-1 stamped into the baseplate near the top of the balance spring. In the third picture you can see the stamp saying 26 jewels.

 

Another image zoomed in shows the 26 jewels a bit better

At this point I wanted to regulate the watch. My previous post listed the performance in various positions. I’m reposting that information here for reference.

regarding the daily rate, it is very consistently +10spd measured on my wrist. Every 24hours I wear it, it gains about 10 seconds, and it gains about 70 seconds in 7 days. So the +10spd is the average daily rate when I wear it 24hrs/day. 

on the time grapher the rates are all over the place.  Amplitude is around 290-300 in all positions. On a full wind the rates are:
Dial up it’s +10spd

3 down it’s +18spd

12 down it’s +5spd

6 down it’s +20spd

dial down its +13spd

9 down it’s +4spd

 

Those rate numbers correspond to the fine regulation screw being at the position shown above. This is how the watch was when I opened it.

I spent about an hour tweaking the position of that screw back and forth while watching the rate change on the time grapher. My sense is that when wearing the watch it runs +10spd and that is the roughly the rate for the dial up position. That indicated to me that I should regulate the watch mainly focused on that single position as that seems to be the effective rate of the watch given my wearing habits.

After several adjustments and trail and error while watching the rate on the time grapher I ended up in the position shown below.

It seems odd to me that the fine screw was not centered for yhe watch coming out of the box from the factory. In the end I just moved the screw back to its centered position which brought the daily rate onI the dial up position to 0 and the crown down to +10. 
I was happy with the new rates, so I reassembled the watch and checked it on the time grapher. The image below shows the rate for dial up.

I’m not sure how the time grapher rates will translate to real world performance so I’ll wear the watch for a few weeks and see how it does.

In any case, I’m happy I didn’t break the movement or case during this adventure. I’ll report back on how it performs in a week or two when I have enough data to assess it.

Thanks for everyone’s help and advice here. I don’t think I would’ve know how to proceed through this process carefully enough to avoid destroying the watch without your suggestions.

[Tudor]

Beat error looks good on the Timegrapher so you’re good. 
 

but you always get beat error as good as possible before attempting rate adjustments. And I personally regulate dial up and crown down. These two positions simulate wear and rest positions. The others are good to get but those two are key for me. 

[VWatchie]

On 8/4/2024 at 2:30 AM, LazyTimegrapher said:

In the end I just moved the screw back to its centered position which brought the daily rate onI the dial up position to 0 and the crown down to +10.

I think that will give you an excellent result. Sometimes you will have to regulate a watch a few times before getting the results you're looking for. I guess you'll now have a watch that will gain less than 5 seconds daily. What people usually don't want is a watch that loses time.

On 8/4/2024 at 2:30 AM, LazyTimegrapher said:

Amplitude is around 290-300 in all positions.

If so, Tag Heuer must have gone to great lengths to accomplish it. I would expect the movement to lose approximately 30° to 40° in the vertical positions. Remember that you must wait for about 30 seconds in each position so that the rate and amplitude stabilise.

[LazyTimegrapher]

18 hours ago, Tudor said:

Beat error looks good on the Timegrapher so you’re good. 
 

but you always get beat error as good as possible before attempting rate adjustments. And I personally regulate dial up and crown down. These two positions simulate wear and rest positions. The others are good to get but those two are key for me. 

I was hoping to only have to tweak the fine adjustment screw given that the watch is basically brand new. I was just unhappy with a brand new watch consistently running +10spd with my normal wear pattern of 24hr/day. I only take it off to shower.

Thanks for the advice on the key positions. I sort of guessed that dial up was the most important since the dial up rate was effectively identical to my average rate through normal wear. I suppose that means I spend far too much time in a chair since the crown down rate didn’t seem to enter into the average rate even though it’s +10spd faster than the dial up rate (both before and after regulation).

8 hours ago, VWatchie said:

I think that will give you an excellent result. Sometimes you will have to regulate a watch a few times before getting the results you're looking for. I guess you'll now have a watch that will gain less than 5 seconds daily. What people usually don't want is a watch that loses time.

If so, Tag Heuer must have gone to great lengths to accomplish it. I would expect the movement to lose approximately 30° to 40° in the vertical positions. Remember that you must wait for about 30 seconds in each position so that the rate and amplitude stabilise.

The average rate I’ve experienced in the two days since regulation are roughly +1.5 spd or +2spd. That’s a 5X improvement from +10spd, which translates to resetting the time once a month instead of once a week in order to keep it roughly within 1min of the correct time.

I’m very happy with the result and don’t find myself wanting to tweak it any further, as it seems easier to make it worse than better at an real world rate of +2spd for a watch with a 10-15 spd difference in different positions. Now dial up is around 0spd and crown down is around +10spd.

As far as the amplitudes, I didn’t pay too much attention to them as they seemed close enough to 300 that I wasn’t worried about low amplitude being a problem. It’s possible it would be lower in vertical positions or after 24hrs of winding down. None of that matters very much to me though as I wear the watch constantly and walk around the house and outside enough to keep it close to fully wound when I wear it.

One other thing to mention is that the balance wheel shows it’s a standard grade movement as it doesn’t have the glycudur balance wheel due to the straight spokes.

[VWatchie]

5 hours ago, LazyTimegrapher said:

The average rate I’ve experienced in the two days since regulation are roughly +1.5 spd or +2spd.

Well, that's as good as it will ever get. Over long periods of time it may come to fluctuate a bit but that's normal and is to be expected.  Congrats!

5 hours ago, LazyTimegrapher said:

I was hoping to only have to tweak the fine adjustment screw given that the watch is basically brand new.

That's what @Tudor was indicating but using a different wording. When regulating a watch you always first adjust the beat error if needed and then the rate. The reason is that adjusting the beat will also affect the rate but not the other way around. In your case the beat error was fine so no need to touch it.

[Tapio]

I was very exited when i saw they do not use plastic movement spacer anymore.

[Drum]

Can I please ask what you used to remove the bezel, and did it come off and go back on ok.

On the watch I have, the triangle on the bezel is slightly off the 12 marker. It is not a lot, but I can't help seeing it all the time. After looking at your photos with the case back removed, I can see the screws that keep the movement into the case. I was going to see if there was any slight adjustment I could make to the movement position after loosening these screws. Would this be the inner 3 screws, or the screws on the outer ring ?. The watch is out of warranty. Thank you.

[AndyGSi]

31 minutes ago, Drum said:

Can I please ask what you used to remove the bezel, and did it come off and go back on ok.

On the watch I have, the triangle on the bezel is slightly off the 12 marker. It is not a lot, but I can't help seeing it all the time. After looking at your photos with the case back removed, I can see the screws that keep the movement into the case. I was going to see if there was any slight adjustment I could make to the movement position after loosening these screws. Would this be the inner 3 screws, or the screws on the outer ring ?. The watch is out of warranty. Thank you.

So is the dial off as the bezel rotates so can be positioned where ever you want.

Photos would help.

[Drum]

Here is a photo of what I mean. The bezel triangle does not align up with the 12 o'clock marker properly after it has been rotated. I know it's not far away, but I can't stop looking at it.