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A bits 'n' pieces 6309 project watch

2073 Views 5 Replies 5 Participants Last post by  Harry, Denmark
Over the past year or two, probably half a dozen or more Seiko 6309 divers have been through my hands, some cushion case 6309-7040's and some the later slim cased 6309-7290's. The 7040's by and large were restored to some sort of original or enhanced original spec. with one receiving a hacking 6306 movement and another a quartz 7546 movement. Two of the slim case 7290's were modified and their stories are told elsewhere, buried in the depths of N54. At the end of this process, I was left with a collection of parts that theoretically could form the basis of another project watch. As several of the other projects had received NOS 6309 movements from dress watches, I was also left with about three or four non-working vintage 6309 movements, one of which looked to be in pretty decent cosmetic condition although would not run at all. The only additional expenditure required would be to source a new domed crystal and a crystal retaining ring but I also bought a polished chapter ring from Noah to liven up the dial.

So, the major obstacle to this endeavour was the movement. I don't propose to go through the whole process but we can have a gander at the starting point and make note of a couple of glitches that arose along the way. So here we have the movement with the automatic winding bridge removed:

This doesn't look too bad until we remove the balance, barrel and train wheel bridge:

and then the barrel

and see just how dirty it is in there. The mainspring also appeared to be broken and so a replacement would be needed when reassembling. I have serviced the top half of 6309's before, so much of this was familiar territory but this was my first complete top-to-toe service involving dismantling of the bottom of the movement. Here's a view of the bottom, partially dismantled:

In the shot above, the hour wheel has been removed revealing the cannon pinion with the date driving wheel still in place adjacent to it. Here are the cannon pinion, the centre wheel and pinion, the hour wheel and the escape wheel and pinion having a bath together:

After cleaning and oiling the movement, including both diashock jewels, and reassembly, needless to say the watch failed to run. After dismantling it again, I discovered that the new barrel that I had assumed contained a mainspring, in fact did not. Doh! So, with a spare barrel and mainspring from one of the other movements installed, again the watch failed to run. I suspected that perhaps one of the wheels on the bottom of the movement was not seated properly and so removed everything again, recleaned and lubricated and this time, the watch ran happily. So, on with the day and date wheels:

and then one of Noah Fuller's dials that I've had knocking about for ages:

and finally the hands. However, disaster strikes yet again. At my first attempt, I fitted the minute hand slightly off alignment (I'm a bit OCD about this) and so off it came but in doing so, I must have somehow dislodged the cannon pinion because I could not then cleanly rotate the hands with the crown set to the second position. Off with the hands, dial, day and date wheels, remove the whole gubbins again on the bottom of the movement and discover that, yes, the minute wheel was fouling the hour wheel. With the cannon pinion refitted (properly this time) and everything back in place everything worked smoothly and we can turn our attention to the case.

The case itself was previously on my second 6309-7290 mod (now sold) but its bezel click ball was recessed, irretrievable and therefore non-functioning. When I sold it the buyer asked me to replace the case with one with the click ball present and so this case then found its way onto the surplus stock pile. Anyway, it is basically sound and had been refinished as part of that earlier project. So all that was required was a clean. Here it is with a polished aluminium chapter ring from Noah and the crystal gasket and ring fitted:

On with a new tempered mineral glass 6105 crystal from Ebay:

and in with the movement, now fitted with a set of plongeur hands from Yobokies and a second hand from Motorcitywatchworks


Now at this point, having been running happily the watch mysteriously started gaining about half a minute per minute. Yes, you read that right. The usual suspect in circumstances such as this is the balance hairspring. The balance will oscillate too quickly i.e. with a much reduced amplitude if two or more of the coils get stuck together and so I removed the balance, dipped the hairspring in lighter fluid, gently stretched it out to dry and refitted. All was well again.

Now we can move to the bezel and some final shots of the finished watch. The insert on this one is taken from a SBBN007 Tuna bezel and had previously been fitted to my 6105/6309 hybrid but that's now gone black again and so this seemed like a good home for the insert.

I think this hand/dial combo works extremely well with this case style as does the bezel. The only thing left to do with this one is to replace the crystal retaining ring (which is cracked) with a new replacement, currently en route from the Philippines.

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That is a beauty and thank you for the detailed shots of the movement, very informative post for a "movement" newbie. Thanks, Sensei Christopher
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