PRS-25 40mm odd behaviour.

[chrisgillett]

Hi all
My Everest came to me in Oct 2019 making it a near antique in this new world of diminutive 36mm offerings. I still love it, but admit it hasn’t had as much wrist time of late since I picked up a BB58 last year and a vintage quartz seiko (7a28-701L - lovely piece).
I gave it some time this weekend and am back in love. BUT. Timekeeping is odd. It lost 5 minutes over a couple of hours. I didn’t think much of it and reset it. Then it ran fast which puzzled me. I’ve tried an app based timegraph (Tosca iPhone app) and it says ‘within -10 to +30’ and no issue with beat to beat either. I’d like/hope this to be more accurate, and it’s not so old that it should require a service routinely I don’t think.
Perhaps with a few more days consistent wear it will settle out?

Love to hear some experienced viewpoints. Thanks.

[walkerwek1958]

Hi all
My Everest came to me in Oct 2019 making it a near antique in this new world of diminutive 36mm offerings. I still love it, but admit it hasn’t had as much wrist time of late since I picked up a BB58 last year and a vintage quartz seiko (7a28-701L - lovely piece).
I gave it some time this weekend and am back in love. BUT. Timekeeping is odd. It lost 5 minutes over a couple of hours. I didn’t think much of it and reset it. Then it ran fast which puzzled me. I’ve tried an app based timegraph (Tosca iPhone app) and it says ‘within -10 to +30’ and no issue with beat to beat either. I’d like/hope this to be more accurate, and it’s not so old that it should require a service routinely I don’t think.
Perhaps with a few more days consistent wear it will settle out?

Love to hear some experienced viewpoints. Thanks.

Forget your phone app, most of them are crap, just do a simple test and use your brain.

Fully hand- wind the watch (approx 60 twists of the crown). Check the time versus a reliable source after letting it run for approx 10hrs in dial up position and calculate the rate/day. Wear the watch for 8 hrs and calculate the rate. If all’s well the rate should be between 0 and +10 secs/ day and the rate on the wrist and rate dial- up should be within 5-6 secs.

I’m happy to service the watch if required, but its worth checking it as I suggested first. The Miyota movements are generally OK but they benefit from being run in a high state of wind.

[chrisgillett]

Forget your phone app, most of them are crap, just do a simple test and use your brain.

Thanks. Will give that a try and report back.

[chrisgillett]

After a few measures I’m getting +25s per day. I’ll try a tiny nudge of the regulator and see how it behaves.

[walkerwek1958]

After a few measures I’m getting +25s per day. I’ll try a tiny nudge of the regulator and see how it behaves.

God loves a trier.........I`ve regulated lots of these movements and even with a timegrapher it's not an easy job. There's no fine adjustment, the regulator itself has to be moved (carefully) and invariably it moves too far, you end up moving back and forth. It usually takes me several goes, I aim to get the watch running at around +5 dial-up fully wound.

Without a Timegrapher you'll struggle, trust me, and it sounds like your phone app is worse than useless.

[chrisgillett]

sounds like your phone app is worse than useless.

Agreed. I’ve deleted it. Just recording the time manually every 6 hours or so, doing the sums and keeping it permanently on the wrist. I’ve given it a *tiny* nudge and hilariously the app said it was going to run faster (hence deleted). Assuming I’m not a complete moron and moved it the wrong way… I’ll see what difference is made after 24-36hrs… then cave and ask for your help!
Thanks.

[chrisgillett]

Success!
Good old trial and error. Also, judicious use of positioning overnight - vertical with crown down - to lose a little time.
+2spd over last 48hrs using manual calculations.

Where is my COSC certificate?