Omega Seamaster 300 165.024 transition to screwed crown... or not

Knudsen1971

So in the end I have the tube custom made from L316 steel. Whoever wants to need to have it done here is the amateur drawing, all diameters are in milimeters 10:1, which is very confusing so, for example 75= 7,5mm and so on:

And to the general topic, here is my research related to usage of Naiad/SD crown, based on pictures of watches, mostly together wit the Extract of Archives.

Knudsen1971

And here it is how the custom made tube looks like, made of L316 stainless, on top is the original Omega 90ST9002 with 2mm neck to case, middle one is the custom made 2,2 mm unpolished, bottom polished one and ready to be mounted on the watch. Thanx again to Archer, who helped me a lot with his measurements to avoid dead ends 😀

tomvox1

Pursuant to a previous thread it was stated by member @Baz9614 that later iterations of the Seamaster 300 reference 165.024 were supposed to be equipped with the upgraded screw-in crown rather than the Naiad push-in originally supplied. The claim was based on this very informative article, which contains the assertion that "The Naiad was fitted to SM300s up until 1967. The screw-down after was fitted after that. As always, earlier versions with screw-down should raise suspicion. The same goes with later models with a Naiad crown. Although this, according to my experience is rarely seen."

Source: http://thatwatchandmore.blogspot.com/2013/03/buying-vintage-omega-seamaster-300.html?m=1

Now I personally had always believed that the screw-in crown was a post-factory upgrade perhaps made at buyer request of the dealer for those more serious about their diving and after the flaws with Naiad system had come to light. I'm willing to accept that I was mistaken in that belief and that later SM 300 165.024s left the factory in Switzerland with the screw-in crown.

However, I still have my doubts about this somewhat early timeline for installation of the screw down crown and the idea that Naiad crowns later than that are somehow worthy of suspicion. So I did a simple, easily duplicated Google image search of "Omega Seamaster 165.024 1968." These are some of the voluminous results, as I always feel sample size is a good way to go in decoding these sorts of trends and changes with vintage watches -- keep in mind that both 26 million and 27 million movement serials are given as 1968 production dates according to Omega's own table:

27.1 mil SN -- Naiad:
http://www.josephbonnie.com/en/prod...00-vintage-ref-165-024-caliber-552-year-1968/

27.4 mil SN -- Naiad:
https://forums.watchuseek.com/f29/f...tritium-dial-plexi-1171-bracelet-4659643.html

27.9 mil SN -- Naiad:
https://www.lunaroyster.com/archive...-300-sword-hands-165024-on-flat-link-bracelet

Serial number blocked but claims 1968 -- Screw-in:
http://www.secondtimearoundwatchco.com/watches-for-sale/a/a/11395

26 mil SN -- Screw-in:
https://www.craftandtailored.com/products/1968-omega-seamaster-300-ref-165-024

26.2 mil SN -- Naiad:
http://watcholdtimes.de/en/produkt/omega-seamaster-300-ref-165-024-from-1968/

27.9 mil SN -- Naiad:
http://www.lionseek.com/watches/bra...aster-300-sword-hands-165-024-on-strap-874ed6

26.2 mil SN -- Naiad:
https://www.thevintageur.com/product/omega-seamaster-300-big-triangle-165-024-diver/

27.1 mil SN -- Naiad:
https://www.europeanwatch.com/21526.html

25.6mil SN -- Screw-in:
https://wannabuyawatch.com/product/omega-seamaster-300-ref-165-024-circa-1967-2/

27 mil SN -- Naiad:
https://www.hqmilton.com/timepieces/eoexy204/1968-omega-seamaster-300-st165.024-A281

27.5mil SN -- Screw-in:
https://www.hqmilton.com/timepieces/40dprp0e/1967-omega-seamaster-300-166.024-big-triangle-4756

27.0 mil SN -- Naiad:
https://www.hqmilton.com/timepieces/mo2leg0x/1967-omega-seamaster-300-165.024-6274

27.1 mil SN -- Naiad;
https://www.stetzcowatches.com/prod...024-1039-bracelet-w-516-end-links-1968-steel/

So as we can see here the Naiad crown is still quite prevalent well into the 27 mil range, which is likely well into 1968 production. We also see some screw-ins appearing obviously and I've also included an early outlier that was almost certainly retrofitted.

This is not say that I draw any hard and firm conclusions other than the apparent fact that the Naiad was not actually phased out by late 1967. It seems highly unlikely that so many of these would be "reversed" for the push-in Naiad either, especially as that requires an entirely different tube and is not just s straight crown swap. In other words if you have a later 165.024 with a Naiad and not a screw-in crown I would have to conclude that it's perfectly acceptable.

As for myself, I still kind of feel like the screw-in crown was some sort of ex-factory option and not really standardized. Otherwise why so many surviving Naiads so late in the 165.024 game? Could be replacing the crown was also a recommended procedure for factory service later on when these watches were turned in for overhaul. Hard to know for sure and YMMV on that. But IMO, both crowns can be found later in production and it should not prejudice the overall opinion of any given 165.024's authenticity. Clearly a screw-in crown appearing too early is another story, of course. But again, if we are looking at an overall customer or Omega-recommended upgrade scenario even that might take on a different hue.

Best to all & all opinions welcome,
T.

bigtriangle68

Is a takeaway from your research that for United States consumers, the Niad crown was used from 1963 - 1970? And that screw down crowns were prevalent for military applications?

Knudsen1971

If you read my post from 2019 above, you`ll be probably able to put 1+1
There was nothing US spec related to crown used.
Facts:
This model was designed for the naiad crown (the cutout in the case is made for the larger naiad crown and SD crown looks a bit odd).
The SD crown was a Military spec, but there are few early military examples with Naiad also.
Most of the civil versions started their live as Naiad crown watch, but large number was converted to SD for obvious issues with Naiad system water resistance.

Knudsen1971

So in the end I have the tube custom made from L316 steel. Whoever wants to need to have it done here is the amateur drawing, all diameters are in milimeters 10:1, which is very confusing so, for example 75= 7,5mm and so on:

And to the general topic, here is my research related to usage of Naiad/SD crown, based on pictures of watches, mostly together wit the Extract of Archives.

Knudsen1971

I have to update my statement, I have found 165.024 with SN 279212xx SEP1970, so it seems like both civilian/military versions were last produced in autumn 1970.
From what I know, the SM300 last appearance in catalog was in 1970.
I almost sure, that the watch above were produced as SD crown watch, nice condition, but very expansive.

bigtriangle68

Any idea when the 552 and 565 movements were discontinued by Omega?

I'm wondering if these movements being phased out might have been a contributing factor to the termination of the 165.024 and 166.024 Seamaster 300.
Can you post a link to the 1970 catalog with the 300? Thanks!

bigtriangle68

Hi Knudsen1971: another idea on fine tuning the entry date of the screw down crowns. Did Omega produce any dated service bulletins or parts brochures targeted at independent authorized watchmakers that mention the screw down crown part number? If so, such a bulletin or parts brochure could help better determine when Omega introduced the screw down crown.

Knudsen1971

552 and 565 were used in another models by mid seventies. Were replaced by inhouse cal 1000 derivates, start of quartz era etc, there is any relation with end of 165.024 model.
The catalog can be found here: http://www.old-omegas.com/