Omega Deville Cal 625

[Knebo]

On 3/29/2023 at 11:03 AM, JohnR725 said:

I find this a very interesting cross reference. Unless you just happen to remember which I do you could go to the website below where they still lists the names of their oils before they had nifty numbers. But classically the Synta-Visco-Lube is 9020. That's an oil my favorite oil for use in just about everything. Then the 9504 is my favorite grease which I wouldn't classify as an oil.

there's several reasons not to oil the pallet fork pivots unless you're Seiko. Then depending upon the tech sheet or maybe when the tech sheet was produced because I've seen at least one caliber that was yes no yes for the pivots but classical a as long as is not Seiko you never oil the pivots at least in a watch. There is several reasons for this in that it's not considered a revolving component so it has  basically nothing to wear out. It has to move really really fast and lubrication can have a dampening effect. In other words you going to lose amplitude and if you are using non-synthetic oils and with time when the oils go bad did really lose amplitude. But it makes you happy a tiny bit of 9010 isn't going to hurt it just isn't going to help either.

https://www.moebius-lubricants.ch/en

then at the next link you get a whole bunch of documents download all that you like but while you're here get number 40 it's for lubrication.

https://www.cousinsuk.com/document/search?SearchString=working

then the problem with official tech sheets are well watches can be old and tech sheets can be old. Plus the tech sheets change with time typically was Omega they appear to be going for heavier lubricants. So then there's the other little problem with the tech sheets they don't tell you everything. I can the case of Omega they will refer you to other documents like the working instructions that is a link for up above but that's only a tiny fraction of the actual working instructions. So if you have the working instructions you find out that they use things like epilam which may explain why they use insanely thin lubricants in my opinion. Unfortunately all those other working instructions are hiding behind well basically you're never going to get those.

for instance they have a working instruction on timing specifications here is the page covering the relevant movements in this discussion.

Thank you very much for this extensive feedback. 

Your first point made me review my understanding of the functions of (thick) oil vs grease in metal-on-metal applications. I now understand. Pheww, that averted some mistakes!! 

Pallet pivots: got it. 

Yes...old technical sheets. The first watch that I fully serviced successfully (about 2 weeks ago) didn't have a technical sheet either and that made me try to understand lubrication, rather than just follow a document. That being said, your first point (oil v grease) showed me that my understanding wasn't fully correct. But now I think I'll do good on my next/ongoing service (of the Omega 625).

 

Thanks again! 

[Knebo]

In practice, the "amplitude 24h" isn't as low as it seems. A comparison with a fully wound movement in a horizontal position would be apples and oranges. 

1. This is after 24h with watches of 30-38h of power reserve. So after 24h they start to run low on power. Don't compare it with a watch with 48+h of power reserve. 

In my experience with Omega calibres 625 and 244, this will cost 60° compared to the fully wound watch. 

2. The spec refers to the lowest amplitude across tested positions. So this will be a vertical position (crown down, when looking at 3 positions only).

This will cost another 40° of amplitude. 

In sum, you loose 60+40=100° compared to a fully wound watch in a horizontal position. 

In other words, when the spec says "amplitude 24h: 170°", you need to achieve at least 270° when the watch is fully wound and dial up (or down). 

And voilà, that's our "usual" minimum target. 

And finally, size matters. As @mikepilkwrote. Getting 270° degrees on a cal 625 with diameter of 17mm is certainly harder than getting the same amplitude on a modern Eta 2824 with 26mm diameter. Another 10-20° difference in amplitude. 

 

On 3/28/2023 at 4:04 PM, mikepilk said:

On 3/28/2023 at 3:50 PM, Knebo said:

 

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One problem with smaller (ladies) watches, is that due to the smaller part sizes, the frictional forces are relatively larger - especially on the smaller balance due to it's much lower inertia.

 

On 3/29/2023 at 11:15 AM, mikepilk said:

That's interesting @JohnR725,  especially "Amplitude 24h". They are lower than I expected. A note for the "amplitude fanatics" - relax 

 

On 3/29/2023 at 11:39 AM, JohnR725 said:

I rather like amplitude fanatics. If you look at the technical specifications of the Swiss companies typically the only worry about amplitude at 24 hours usually in a specific position or basically they only worry about amplitude at 24 hours. The Omega timing  specification as you've noticed as long as the watch maintains time the amplitude can be low very low. Low enough that on this group would have to probably tranquilize some people.

then even though the timing specification goes on for a sizable quantity of numbers they even have vintage in case it's not listed. No notice that the acceptable amplitude for the smaller watches is much lower but the timing specifications are not as great. Then in case you're curious what three position timekeeping as I've attached that. That's all they officially care about but if you're testing your watch it's always nice to look at it and six positions just to see what it's doing just remember the official timekeeping specification is not for six position unless it's a chronometer. Which typically a ladies movement is not.