4 ms·

I'm glad that this is a thing but I don't know what it means for the average horological enthusiast. Lots of the goodness of a movement comes down to manufactur

I'm glad that this is a thing but I don't know what it means for the average horological enthusiast. Lots of the goodness of a movement comes down to manufacturing tolerances, grading, and regulation at the factory. My ETA 2824-2-powered Damasko loses one second per day on the wrist despite having been dropped, jogged with, and high-sided on a motorcycle; there are watches that cost five times as much with the same model of movement that came from the factory running way worse. The engineering is already there as Chinese factories are cranking out affordable 4Hz movements, it's just that the finishing and assembly still leave some to be desired (according to random YouTube reviews and forumites at least). This isn't a knock on Chinese factories by the way - they do FANTASTIC work for the money (and I'd love to add a PT5000-powered piece to my modest collection) but they just aren't on the same level as their Japanese/German/Swiss counterparts.

HeyLaughingBoy 5y ago
The hobby machinist community has been buying cheap Chinese milling machines and lathes for decades and disassembling them to fix poor finish and assembly (replacing bearings, scraping or polishing bearing surfaces, better fasteners, etc.) and then reassembling to result in a much higher quality machine at a reasonable price. Could something similar happen with watch movements?
- samatman 5y ago
  It not only can be done, it routinely is. Especially with the Chinese watches, they often come from the factory with less-than-perfect attunement. Watch repairmen will take a watch like this, clean everything, maybe replace a bearing or two, use high quality lubricant, possibly even swap a gear or so if it needs it. They can also take an older mechanical in pretty bad shape and restore it to health. There's a point of no return for any mechanical device, of course.
kenneth 5y ago
My Omega Seamaster gains ~2-3 minutes a month (so roughly 4-6 seconds a day.), it's rather annoying but I understand that it's pretty common for an automatic mechanical watch.
- Badfood 5y ago
  For something mechanical operating under random g forces and over a wide temperature range, that accuracy is truly astonishing.
  - kenneth 5y ago
    Fully agree, automatic mechanical watch movements are truly a marvel of engineering. The fact that the movement is powered purely by the kinetic forces naturally applied from wearing it, and can reasonably accurately keep time over years, under a wide range of conditions… is truly impressive.
- TheManInThePub 5y ago
  > My Omega Seamaster gains ~2-3 minutes a month (so roughly 4-6 seconds a day.) That falls within the bounds of accuracy required of a Swiss certified mechanical chronometer (that is to say, a clock accurate enough for marine celestial navigation) and is pretty good. As a marine engineer I have a genuine and real appreciation of mechanical chronometers, though any working watch/clock I use will always be quartz as for accuracy and price, nothing else comes close. https://en.wikipedia.org/wiki/Marine_chronometer https://en.wikipedia.org/wiki/Marine_chronometer
usrme 5y ago
Did you have it regulated? Asking because my Tudor Heritage Black Bay 79220R uses the same movement, but will lose around 30 seconds in a week... I mostly wear it when I'm not all that active (e.g. in the office, out about in the city, etc.), but it still seems too much to me.
- cpcallen 5y ago
  That seems surprising bad. Maybe not strictly out of tolerance, but definitely something that could be considerably improved by having the movement regulated (or perhaps serviced, if required). Is it still under warranty?
  - usrme 5y ago
    Not from the manufacturer, no. I bought it second-hand and the seller does offer a 36-month warranty for any mechanical dysfunctions, though I'm not sure whether something like this would qualify. Even if it did, I'm not all that enthused about bearing the costs of sending the watch to way across Europe if it could just be regulated by my local watch shop instead. Am I understanding correctly that if I had it regulated, then it the deviation would be minimal for years to come or how exactly would that pan out accuracy-wise?
- TheManInThePub 5y ago
  Loosing 4 seconds per day (28 per week) falls within the bounds of accuracy required of a Swiss certified mechanical chronometer and is pretty good. https://en.wikipedia.org/wiki/COSC https://en.wikipedia.org/wiki/COSC [I made a similar comment further down.]
- alexjplant 5y ago
  Nope... came from Germany that way. As other have notes though losing ~4 seconds a day is pretty accurate all things considered. Seiko's 3Hz movements can gain or lose _half a minute_ a day and still be considered within spec.
growt 5y ago
I have swiss (ETA based), Japanese (Seiko) and Chinese watches. I think one of the Chinese watches I own is the most accurate and reliable of all of them.
- question11 5y ago
  which model chinese watch?
  - growt 5y ago
    It's a sea-gull aqua Terra homage. With a sea-gull movement.

HeyLaughingBoy 5y ago

The hobby machinist community has been buying cheap Chinese milling machines and lathes for decades and disassembling them to fix poor finish and assembly (replacing bearings, scraping or polishing bearing surfaces, better fasteners, etc.) and then reassembling to result in a much higher quality machine at a reasonable price. Could something similar happen with watch movements?

samatman 5y ago
It not only can be done, it routinely is. Especially with the Chinese watches, they often come from the factory with less-than-perfect attunement. Watch repairmen will take a watch like this, clean everything, maybe replace a bearing or two, use high quality lubricant, possibly even swap a gear or so if it needs it. They can also take an older mechanical in pretty bad shape and restore it to health. There's a point of no return for any mechanical device, of course.

kenneth 5y ago

My Omega Seamaster gains ~2-3 minutes a month (so roughly 4-6 seconds a day.), it's rather annoying but I understand that it's pretty common for an automatic mechanical watch.

Badfood 5y ago
For something mechanical operating under random g forces and over a wide temperature range, that accuracy is truly astonishing.
- kenneth 5y ago
  Fully agree, automatic mechanical watch movements are truly a marvel of engineering. The fact that the movement is powered purely by the kinetic forces naturally applied from wearing it, and can reasonably accurately keep time over years, under a wide range of conditions… is truly impressive.
TheManInThePub 5y ago
> My Omega Seamaster gains ~2-3 minutes a month (so roughly 4-6 seconds a day.) That falls within the bounds of accuracy required of a Swiss certified mechanical chronometer (that is to say, a clock accurate enough for marine celestial navigation) and is pretty good. As a marine engineer I have a genuine and real appreciation of mechanical chronometers, though any working watch/clock I use will always be quartz as for accuracy and price, nothing else comes close. https://en.wikipedia.org/wiki/Marine_chronometer https://en.wikipedia.org/wiki/Marine_chronometer

usrme 5y ago

Did you have it regulated? Asking because my Tudor Heritage Black Bay 79220R uses the same movement, but will lose around 30 seconds in a week... I mostly wear it when I'm not all that active (e.g. in the office, out about in the city, etc.), but it still seems too much to me.

cpcallen 5y ago
That seems surprising bad. Maybe not strictly out of tolerance, but definitely something that could be considerably improved by having the movement regulated (or perhaps serviced, if required). Is it still under warranty?
- usrme 5y ago
  Not from the manufacturer, no. I bought it second-hand and the seller does offer a 36-month warranty for any mechanical dysfunctions, though I'm not sure whether something like this would qualify. Even if it did, I'm not all that enthused about bearing the costs of sending the watch to way across Europe if it could just be regulated by my local watch shop instead. Am I understanding correctly that if I had it regulated, then it the deviation would be minimal for years to come or how exactly would that pan out accuracy-wise?
TheManInThePub 5y ago
Loosing 4 seconds per day (28 per week) falls within the bounds of accuracy required of a Swiss certified mechanical chronometer and is pretty good. https://en.wikipedia.org/wiki/COSC https://en.wikipedia.org/wiki/COSC [I made a similar comment further down.]
alexjplant 5y ago
Nope... came from Germany that way. As other have notes though losing ~4 seconds a day is pretty accurate all things considered. Seiko's 3Hz movements can gain or lose _half a minute_ a day and still be considered within spec.

growt 5y ago

I have swiss (ETA based), Japanese (Seiko) and Chinese watches. I think one of the Chinese watches I own is the most accurate and reliable of all of them.

question11 5y ago
which model chinese watch?
- growt 5y ago
  It's a sea-gull aqua Terra homage. With a sea-gull movement.