This is a historical watch for Seiko fans and collectors. The Seiko Sportsmatic (418970) This was the first Seiko “5” model! The Sportsmatic 5 was launched in 1963.
The 5 was named by Seiko from the following points. (Source https://museum.seiko.co.jp/en/seiko_history/milestone/milestone_05/ )
1.Self-winding (allowing high winding efficiency)
2.Water-resistant mechanism (protecting quality for many years)
3.(Visible) day-and-date-integrated window in the 3 o’clock position
4.Crown (which does not require manual winding) hidden in the 4 o’clock position
5.Masculine design (with a metal band)
My watch was is dated July 1964 so still an early version. This one has also been a very long project indeed. I had the watch in 2018 and its not been completed until 2021!
It was in very poor shape when I got it. Wrong stem and crown were fitted that just didn’t really work well. Movement was running intermittently and I was relatively inexperienced in 2018 and had never even seen one of these yet alone work on one.
Despite this I still opened it up and started the disassembly. I blindly took it apart taking some photos along the way.
I cleaned all the parts and started assembly. It was pretty straightforward on the main movement side but the dial size threw up some difficult challenges. Firstly the keyless works as they were not working correctly I had no idea what might have been causing this or if any parts were missing. I remember fumbling with this for hours until finally getting it in place. There is a quite difficult Sheppard crook spring that pushed the lever which holds the date wheel in place until the next change (I forget the name of this part)
Once this is in place you have to carefully fit a cover plate over the top, once false move and the spring launches itself into orbit.
Once this was fitted it was then I noticed that a spring was missing, it should fit under the cover plate in a recess and its responsible to hold the day wheel in place between changes! damn. As I more recently found out this was fitted on many models and is quite delicate and very easily lost. Did I loose it on disassembly in 2018? who knows..
I could not find this part online so decided at the time to make my own as I had a bunch of old springs. I fashioned quite a few and one worked but not very well.
By this point the movement was also not working great either and in the end I gave up completely and put it in a container in my “to do” pile.
By 2021 I had gained more experience and had worked on similar movements with success but never really gave this watch a thought until one day when I was asked to service a watch for a friend it was the same movement! well it was a 6619 and my watch says 410. I believe the 410 and 6619 to be the same movement.
On working on this watch I found that there was also a very small ring that was fitted between the train cover and the 4th wheel (second hand wheel) its like a spacer. I didn’t remember seeing this on my watch all those years ago.
Once finishing my friends watch I immediately stripped mine down again to find that the small ring was missing.
I went onto https://speedtimerkollektion.com/ site which is a place I buy donors from and searched to 6619 and I was in luck he had some movement only watches. I bought the cheapest at around £25. I scavenged the spring and the ring from it and re-cleaned the movement and assembled. This time a lot easier than in 2018. Still a fiddly movement with nice gotcha springs all the same.
With some fettling I was able to get it running well enough to wear although I may well change the mainplate as mine as clear marks there a previous watchmaker has tried to lift the balance cock to adjust endshake by scouring the mainplate there the cock screws on thus making it fit slightly higher.
For now though I just want to enjoy this watch. It is quite large for the era and has a lovely vintage look. Also knowing the significance of the model makes it more special.
So here is is.
