how to test accuracy for automatic watch and wat is the acceptable range?

[ykl]

hi all the sifu here, am new to automatic watch, would like to ask how to test the accuracy of the watch? and wat is the acceptable range?
thx in advance! 

[TheHobbit]

Got a quartz watch? Time it against the quartz watch. Set the time against the quartz watch and check after 24 hours. See if gain or otherwise. Acceptable limits? Is it a COSC rated watch? How old is the watch? How new is the watch? How often do you use the watch? What are your limits when it comes to mechanical watch accuracy?

[ykl]

hi, is not COSC rated and is a new one, wear quite frequently, just wish to know that how much differential in time is call abnormal...
acceptable range think within 3-5min is ok...

[ck77]

3 min is ok?
after 5 days your watch will be slower/faster by 15 min!

[dsiewmy]

3 min is ok?
after 5 days your watch will be slower/faster by 15 min!

LOL, every week have to reset your watch. pretty damn troublesome.

i think he meant 3 mins every month which is still not too great.

[ykl]

haha... wat i mean is 3 min after some period of time should consider ok to me... and the most important part is that is there any standard range as a guide to know whether the watch is working normally? eg, the watch faster than 15 second is normal, then faster than 30 second is abnormal... got standard like this for watch?

[takashi78]

Again, without you giving us details on what watch or movt you have there is no way to tell.

A watch is a precision device so "some" period of time is very subjective. What is some? 1 day? 1week? 1month? 1year?

[TheHobbit]

Quoting from MIL-W-46374D, US military spec for watches:

"Accuracy tolerances of the specification call for plus or minus 60 seconds in 24 hours."

It is certainly not within COSC spec but good enough for the military. Now you know why in all those Combat shows, the soldiers will always sync their watches before the start of a mission.

To answer your question, there are standards but it is watch and movement dependent (not forgetting people). 

[ykl]

Again, without you giving us details on what watch or movt you have there is no way to tell.

A watch is a precision device so "some" period of time is very subjective. What is some? 1 day? 1week? 1month? 1year?

the movement is automatic caliber ETA7750, thx all for the tolerant of my stupidness here... hehe...

[takashi78]

Well...a simple search on google got me this info in 1sec
http://en.wikipedia.org/wiki/ETA_SA

[Gigi]

my seiko OM time i set 5 min slower than mine g shock and 3 weeks had passed and i notice the OM time its still -/+ 5 min or 4 min.

[sanguoich]

I think Seiko automatic watches are accurate to 20 seconds per day.
3 minutes per day sounds like my hand winding vintage watch. 
But a brand new watch shouldn't be off by that much.

Quartz watches aren't 100% accurate, but they are very good way of timing your automatics to get a good idea of how far off it is.

Also pay mind that the accuracy of automatic watches may be sensitive to how you wear your watch eg clapping, fast movement of your hand etc..

[siodee]

If your watch is still under Warranty, send it back to calibrate the watch. Automatic watch is always like that