Great video of a DIY battery change on a 9F - gorgeous movement and duct tape trick
 

9:00 is where the caseback is off showing the beauty of the 9F

The coolest part for me tho was using duct tape to remove the caseback with NO other tools. Amazing ingenuity and the owner sounds drunk.

https://m.youtube.com/watch?v=WFY7qtY3X8c

I use the duct tape trick too, it works great. I learned about it here... :cheers:

It's quite easy to do, but as there is a Seiko Service Centre nearby, I like to take my GS and Tunas in for the battery change. It costs $40 but you get a pressure test (up to 10 bar) included and a some official paperwork to throw in the box. My SBGT235 is due to start the three-yearly two-second-jump battery alert any day now, and it's only gained about six seconds since the last change. Kinda looking forward to going in and checking out the display cases and picking up some catalogs.

Wow , HK$40 is such a bargain for a new battery and pressure text. Next time visiting HK, I will bring my 9F.

That's pretty cool! I've seen some watchmakers use a caseback removal ball, but had no idea duct tape worked also.

It's great because some of the removal tools can leave marks in the metal eventually. Thanks for sharing, CJ! :cheers:

9F amazing engine.
Thanks for sharing!

That's US$40 or HK$300 :cheers:

The service box and paperwork are well worth sending it in too.

Thanks for sharing , enjoyed the video and the duct tape truck!

It cost me $65 to have battery change and pressure test on my GS, so not sure i would myself .


Sent from my iPhone using Tapatalk Pro

The great thing about the 9F is that battery changes are easy and the movement is sealed. A $15 case opening kit, $5 gasket lube, a $3 battery and a $150 pressure tester gets you there. After you buy all of that, then it’s just a few bucks for the next battery swap (I have 2 9Fs.)

Takes all of 5 minutes to do the whole thing.

Wow!

Why do you have the watch underwater at 6 Bar Douglas?:thinking:

Are you trying to fill it up?:chuckle:

It’s a common watch pressure tester. You pressurize the watch with air above the water for a couple of minutes, lower it into the water, and then release the pressure. If air starts escaping (bubbles) when you release pressure, then you quickly raise the watch out of the water, so water doesn’t enter the case (watch fails test.) If no bubbles stream out of the watch, then the watch is sealed (watch passes test.)

I don’t plan on sending my 9F watches into GS unless they either stop working or fail this pressure test. Potentially decades-long service intervals are part of the beauty of the 9F quartz.

Be nice if GS made a 9F watch that showed the interior mechanism, but I guess the extra-long service interval depends on that "sealed cabin" as they call it.

For anyone interested, here’s my ‘96 9F82A compared to my ‘13 9F61A, so you can see the differences in finishing. Also, there’s a shot of the soft iron cage covering the movement of my ‘13 SBGX093.

Interesting comparison in finishing. How's the timekeeping on the '96? Still -/+10s per year?

Don’t know exactly, but still good. However, the date wheel mechanism broke, so need to send it in.

Hi Douglas,

You have pressurised the watch for ‘a couple of minutes’ and submerged it under pressure at 6 Bar at least long enough to take a pix.

Let’s take a typical diver watch with a very small leak.
After ‘a couple of minutes’ above the water at 6 Bar the pressure inside the watch might only have reached 3 Bar.
When you drop the watch into the water the pressure inside the watch continues to increase towards 6 Bar but now it is being pressurised with water not air.

The pressure must be reduced just as the watch is being submerged as any delay could cause water ingress.

To prevent this happening I converted my wet pressure tester to a deflection dial.

:cheers:

Ah, now I see what you were saying. The watch had already passed the pressure test, and that quick pic was after the fact for dramatic effect. However, if you’re saying 3-5 minutes isn’t enough time for the pressure in the watch to get to 6bar, then maybe I dodged a bullet. I’ll take note of everything you said, and I’ll see if I can delete that photo so it doesn’t mislead anyone on the process. :cheers:

When I saw the watch under water at a pressure of 6 Bar I though the test was in progress.

I didn’t realise it had passed the test?

:cheers:

Yeah, sorry about that. I re-pressurized and took that pic to send to a friend, but the watch had already passed earlier. Didn’t mean to cause confusion. :cheers:

I would not pressurise a watch under water even if it had just passed a ‘dry’ test.

Your watch is most likely ok but seals can sometimes be contrary and now do you really know if there is water inside the watch?

I pressurized it again above the water for a while before I dropped it in and quickly took that pic before releasing the pressure, and no air was displaced when releasing the pressure. I’ve not seen evidence of water inside via humidity or anything since the pic was taken. I’m not too worried about it. I also wear the thing in the shower every day. :rofl::cheers: