How accurately should I try to get my Seiko automatic to run?

[Mabouya]

A few weeks ago I got a new SKX007 (7S26 movement) and so far I love it.

My only real issue is the accuracy. Out of the box it lost about 45 seconds a day. I took it to a local shop (recommended to me on Watchuseek) and they tweaked it. It's now lost a bit over 1 minute over three days, so it's down to about half of the previous rate, -20 seconds a day. I've read that the 7S26 should be good for +/- 15 secs a day or better.

They only charged me $10 for regulating it, and I have no problem paying $10 more to have them try again. Am I asking too much if I take it back, hoping that they can get to, say +/- 10 secs per day?

(The last time I had an automatic was in high-school, so maybe I'm just not used to living with an all-mechanical watch.)

TIA

[spopepro]

I'd ask them to adjust it again. There are some here with much more experience with that movement in particular, so they would know for sure. I feel like a reasonable expectation is not having to set the time more often than moving the date forward.

[Justin@BlackOakVelo]

I have a SKX007J and when I first got it, it lost a minute every few days. The more I wore it, the better it got.

Keep it on all the time.

Great watch by the way, enjoy it.

[Jason Musgrave]

If it's new give it ~3 months before you start messing with it. They take a bit to "settle in."

[TACSTS]

Yeah like others have said - give it a solid couple months of wear and re-time it. That said my SKX007J has averaged about -3 sec since new so the 7S26 movement can certainly be accurate. I also have the same movement in another watch that gains 30-45 sec a day. Its really a crap shoot with these more economical mass produced movements that aren't regulated from the factory. But I think that is part of the charm of these Seiko auto's. Let's face it - if you want accuracy go buy a $10 timex and you'll never need to reset it.

[Mark Kelly]

I know that the crystals used in Quartz watches are cut so as to be at their most accurate when the back of the watch is near body temperature (eg the watch is being worn). Is this also the case with mechanical movements?

[Curt Goodrich]

I know that the crystals used in Quartz watches are cut so as to be at their most accurate when the back of the watch is near body temperature (eg the watch is being worn). Is this also the case with mechanical movements?

Mechanical movements are effected by temperature. Lubrication viscosity changes along with expansion and contraction of the metal have an effect on the movement's accuracy. I doubt though that regulation is based on a temp of 98.6. My watch repair friend says regulation takes time and experimentation. The repair technician can make an adjustment but won't know if that's enough or too much until a period of time later. That's why a full blown regulation can cost more than $10 and mean leaving the watch for some time. Don't give up on the Seiko. If my SKX007J is an indication, that movement is capable of very good accuracy. Mine currently has gained 2 minutes over the last 60 days. And it goes without saying, part of the charm of the mechanical movement is being in tuned to the individual quirks of each watch.

[Mabouya]

That's why a full blown regulation can cost more than $10 and mean leaving the watch for some time.

Curt, I understand what you're saying, but for the record, I would have gladly paid more, especially if he can get it to +/- 10 secs / day.

[Curt Goodrich]

Sorry. I wasn't implying that you were being cheap. Just that you'll probably need to find someone that holds onto the watch for a bit and charges a bit more. Good luck.

[Mark Kelly]

I doubt though that regulation is based on a temp of 98.6.

The crystals are cut to be most accurate at about 28 degrees, apparently that's the standard for "wrist temperature".

On the changes in the mechanicals with temperature: one of the things Harrison invented for the H1 chronometer was a pendulum with a CTE of zero (and this was before invar was discovered), also none of his chronometers except H4 had lubricated bearings. Insanely clever man.

[funcrusher]

I have several mechanical watches...they all keep shitty time

But they're pretty to look at

With all the possible variables you're asking a lot for perfect...if you want perfect get an atomic watch (I have one too) but they're not nearly as enjoyable

[fastupslowdown]

I have a Breitling purchased a decade ago with the old Valjoux movement. It keeps good time, I do adjust it about a minute or two about twice a year. Every 4-5 years it starts to slow down, but this is nothing more than a warning to me that it needs a cleaning and basic maintenance upon which it returns to good performance. I love the ticking and wind-up sound of a good automatic watch. -Mike G

[WayneJ]

The 7S26 movement is capable of much better accuracy than you're experiencing. I have one that I use as a beater and it's about +5s/day. It measure +12s to +15s/day on the Timegrapher in most positions, but is far more accurate on my wrist. Don't forget to give that watch a thorough winding of the mainspring by using the orbital shake method before wearing it. And as others have said, let it go through a break-in period before making any more adjustments.

[aingeru]

Watchmaker here... if I recall correctly you cannot hand wind that movement meaning that when you wear after the watch has stopped you will need some hours of regular use until the balance gets a decent swing. Think about it like this: further the balance wheels swings, less are the inherent errors in the watch going to show. For now forget about the rate. What you need to do is to have the watch checked for amplitude on a timing machine (all six positions) when fully wound (usually they can print the results). The balance wheel should be swinging at least 270° on the dial up position and should not lose more than let's say 40° when in vertical (I would test it crown down). Now if the watch has enough amplitude, you can try to improve the accuracy of the watch by regulation. If there is not enough amplitude then the watch will need a complete overhaul( I now, it's new) which will involve adjusting to improve precision. Accuracy vs precision:
Accuracy Vs. Precision: Understanding Watch Performance | Revolution Press
Get that print and come back here. Glad to help

[Mabouya]

Guys,

Many thanks for all the help and suggestions.

I've decided to give it another month or so of wrist (and winder, since it isn't my only watch) time, at which point I'll see where we stand. Right now it's at about -3 minutes / week (last time I set it to http://tycho.usno.navy.mil/simpletime.html was exactly a week ago).

In the meantime I'll just get used to adding a few minutes to what it tells me.

M

[theflashunc]

This thread has had the opposite effect. Between this and the thread elsewhere, I was caught in a fever pitch and walked away from my local Seiko counter with the US version. All of you are enemies to my bank account at this point. But my wrist is very happy.

[Mabouya]

Cool.

The 173 has the rectangular markers instead of the round and oval ones on the 007. And the second hand is a bit different.

I hope it's as accurate as you want it to be.

[theflashunc]

I'm going to give it a break in period and see where we land. I'm okay with some variance on either end. Part of the charm of an automatic. We'll see how much I can tolerate. If I'm super anal, there's always my phone or my quartz watch if I need to know down to the second.

[randonneur]

If the charm of an automatic gets old, you could just get a solar one and be done with it :)

seiko.jpg

[Mark Kelly]

if you want perfect get an atomic watch (I have one too)

wrist-5071a1.jpg

Courtesy leapsecond.com