Watch Thread

I've been wearing my dad's Seiko 5 a bit more lately and I'm investigating it's accuracy and some tweaks I can do. I found this nice little site that helps me keep track of accuracy

https://watchaccuracy.com

No ads and no sign-up. It store the data with a cookie. Since Dec 5th I've been recording the errors and was planning to do it for an entire month but I messed today and the reserve ran out so I need to start over. Nonetheless these are my results


The stated accuracy for the current Seiko 5 watches is +40/-20 seconds per day and my watch from the 80s with the 7009 movement was certainly in the range. What I noticed though was that it was consistently gaining 30s a day. It was actually pretty precise at 28 +/-4 seconds and I thought maybe it was magnetized or I could adjust a lever to get it a bit more accurate.

I was researching the 7009 at 17jewels.info which didn't tell me too much but I saw that the updated (and current) movement is the 7S26A. More important though is that they include a table of independent measurements.



Dial up is exactly how I keep my watch when I'm not wearing it and the time gain is in line with what I was experiencing. I decided to keep my watch sideways to see what I would get



I boxed the days I did this in red and you can see that the error is easily halved!

I'm also keeping track of a couple quartz watches I have. Here are the errors I have since Dec 2nd

Casio G-shock: 0.4s/day error. 8 second total deviation
TAG Heuer Formula 1: 0s/day error. 0.5 second total deviation

The TAG is basically below the limits of what I can measure by eye and I would need camera to compare. I would need to wait a few months to really see any meaningful deviation with the TAG.

Temperature does affect quartz movements and they often take into account the watch being in body contact for accuracy. I'm not currently wearing the Casio so the higher deviation might reflect that

 

Gaining is preferable to losing IMO. If it is fast you can just pull out the crown to stop it for a bit. If it is slow you have to also manipulate the hands to reset it.

I also have a TAG Heuer Formula 1 Chronograph as my daily wearer, and am very impressed at how accurate it is. I set it to my computer, which would be NTP stratum 3 (so within a few hundred milliseconds of actual time), and it is probably accurate to within a second or two a month, which easily makes it the most accurate timepiece I have ever owned (excluding smartwatches).

I like mechanical watches, but there are definitely some things to like about quartz too.

 

I’ve always been interested in super-accurate movements and especially quartz that pushes the limits. Seiko which pioneered quartz watches even grows their own crystals for their Spring Drive as well as their 9F quartz movement which is +10s/-10s a year! Citizen I think has surpassed this down to a second

 

I had another stretch before I forgot to wear the Seiko again. Supposedly there's a 48hr reserve but since there's no crown winding so I either have to wear it constantly or get a watch winder. Not really worth it for a Seiko 5. Nonetheless here are the results:



I played around with the positioning a bit and I found that dial-down gave me the best results under +10s, even with an error of only 3.2 seconds!

I'm going to try to start over Jan 1st and go for a whole month

 

I don't own anything officially certified, but it is interesting the testing they undergo with temperature and position being the key variables.

https://en.wikipedia.org/wiki/COSC#Standards_and_methods

 

I don't know if you all care enough about timing to get one, but I have seen several watch Youtube channels use timegraphers: https://www.amazon.com/OTOOLWORLD-Tester-Multifunction-Timegrapher-NO-1000/dp/B0081SSJZG/

When I was putting together my own watches, I probably should have gotten one, but now that I wear a smartwatch 90% of the time, I kind of missed the "need" window.

 

I'm not sure what I would do without one... makes regulating the watch so much easier
-----edit-----
along with this app https://play.google.com/store/apps/...d.apps.atomic_clock_watch_accuracy_tool&gl=US

 

Interesting app. Assuming it connects to a Stratum 1 NTP server that would make the phone Stratum 2, which should be within 10s of milliseconds of actual time. Many phones typically get their time from the network using NITZ, which is similar to NTP but is actually part of the GSM cellular network standard. NTP is more accurate though, and I note as of Android 12 NTP is prioritized over NITZ (which is a reversal from the previous order).

https://source.android.com/docs/core/connect/time-source

No idea what Apple devices choose as priority for time info.

 

What exactly does a timegrapher measure? Is it just the ticks and it extracts information from that?

I’m wondering if I can use a camera I already have and count frames between cycles to get some of the same timing information

 

A timegrapher listens to the balance wheel beats per hour. Depending on your movement frequency it can be measured pretty accurately.

I had my Panerai Luminor GMT checked on a timegrapher recently and it is only +2 sec/day. I was surprised being 8 years old!

The movement is based on an Valjoux 7750-P1, which is based on a ETA 7750 that is COSC certified crono.

I keep wanting a reason to send it in for service but now worried it would not come back as accurate....

 

Starting a watch thread is a great idea! It's always interesting to see what watches other people have and hear their thoughts on them. I see you've mentioned your Omega Speedmaster Perpetual Calendar Chronograph, it's a great watch and a great choice. Omega is known for its high-quality watches and its rich history. If you're looking for more options, you can also check out *link removed*, they are affordable and can be a great way to add variety to your collection without breaking the bank. It's always fun to see the different watches people have and to hear their thoughts on them. Happy to see this thread!

 

Here's my vanity purchase in observation of my 60th birthday last month: a vintage Aquastar 63 (1963 model, like me). This one is branded Duward, purportedly showing it was made for the Spanish market - apparently re-branding to avoid tariffs was common practice in pre-EEC days. Lorenz (Italian market) is another common brand variant of this model.



The sunburst dial and domed crystal make it a bit tough to photograph convincingly, but the dial, text/numbers, and original tritium lume elements (which of course don't glow any more) are all in very good shape, even though the case has some big divots out of the crown side.

I've always had a bit of a boner for vintage tool watches - old tools attract old tools, perhaps - and this one fits the bill: a 60s 200m diver with one of the earliest, if not the earliest, internal rotating bezels (bi-directional, positioned using the main crown; there was a patent associated with it but I'm not sure if it was for the setting mechanism or the internal bezel itself). Internal-bezel divers seem to be making something of a comeback (eg these Baltic and Longines models), and many retro-inspired ones are also going back to smaller diameters (like the 37.5mm of this one; smallish though that is, the long lug-to-lug distance makes it seem big on my skinny wrist).

The crystal came up nicely after rubbing with Polywatch, and the case is a bit smoother after a going-over with Silvo but could still be improved with a bit more work. On receipt it was gaining 1-2 mins/day and running down in less than a day if unworn (the automatic movement's power reserve spec was 40 hours), but after service by a local vintage watchmaker and some trial-and-error regulation by me, it now keeps going and has accumulated averaged < 0.5 sec loss in the last 18 days.

Downsides: the low-contrast scheme, small size, and lack of lume make it tough for my ageing eyes to read in low light; and the crown is easily knocked anticlockwise so consequently the bezel is easily moved out of position. Also, it's not likely to be too waterproof any more. I've replaced the rear seal but haven't yet pulled it apart to replace the crown gasket. I intend to do that, though, because it might give the winder a bit more friction and therefore keep the bezel in place better.

 

That's quite an acquisition and it looks like it has been well-used. I especially like the internal rotating bezel. I have a Boldr microbrand with this same feature. I'm only ten years your junior, and I've started carrying a AAA flashlight to help me read my wristwatches. Like you, I tend to favor watches under 40mm.

I hope you enjoy that watch for many years.

 

My latest acquisition and my first COSC watch