Seiko - Seikomatic Slimdate - Calibre 840 - 30 Jewel Automatic

Just in this past week or so was this slightly neglected Seiko Slimdate featuring a stunning 30 jewel automatic movement. Seiko collectors eyes light up when it comes to the fancy and famous pieces (Pogue, 62MAS, SKX etc ) but there are plenty of great quality pieces that are very under appreciated and certainly worth collecting.

This gem is not a customer watch but one i found at auction and it seemed in fairly good condition for a gold plated Seiko as most tend to be badly worn. The styling is simple but smart and originally this line of watch would have been intended for the businessman of the era but could easily have been worn for evening occasions as well. The watch is fitted with a high quality 30 jewel automatic movement in the form of the calibre 840 ( Suwa Large 1963-1969 ), although there were higher jewel counts available i think 30 jewels is plenty enough.

Below is a series of photos during the strip down, we can see an advanced auto winding mechanism when compared to the single stage gearing of the more modern 7S26 style movement calibres. Also visible is the indirectly driven seconds pinion as you would find on high quality Swiss watches of the same period ( or even today for that matter ). Note also a small winding gear for the watchmakers benefit in order to manually wind the movement prior to testing :)
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As is fairly typical after years of use the crown has seen better days, so this would need to be changed for something new. Finding originals can be hard work but thankfully there are a good amount of generic crowns that can work and are of equal quality.
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Not much material left here, thankfully its not manual winding :)

After some TLC and a good service the watch was finally ready and boy did it shine ! Im not a fan of gold watches but sometimes you can just admire something for what it is and this Slimdate is one of those things. Feel free to view the gallery photos >>
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I could not source an original glass for this model but luckily i did find a nice flat glass with an attractive bevelled edge to give it that extra wow factor, sadly this is harder to show in photo form than real life :)

More blogs to follow so check back soon !