Omega 35,5L-T1 documentation ??

[Endeavor]

Hello All;

Has anybody among us some technical information about the Omega 35,5L-T1 movement? Build end 1920's, early 1930's?

The caliber number is stamped on the main-plate, below the balance and is written with a comma, 35,5L-T1. In English documentation it may well be written with a dot; 35.5L-T1.

So far I assumed a lift-angle of 50 degrees.

[Endeavor]

Nobody nothing ?

@nickelsilverperhaps?

[VWatchie]

I did spend a few minutes searching it but came up empty-handed. I (and I'm sure you as well) did find a comprehensive list of Omega lift angels but no luck. Perhaps someone could make a qualified guess based on a similar Omega calibre?

[Endeavor]

Yes, I've seen that list too. Perhaps in this list they didn't bother with the comma or the dot and describe it as a 355?

Anyhow, it is indeed from this list where I took the assumed 50 degrees from

Currently the movement is in parts and if in the meantime no info is found, I'll find the lift-angle via the 180 degrees amplitude timegrapher trick.

Edited February 4, 2023 by Endeavor

[JohnR725]

59 minutes ago, VWatchie said:

Perhaps someone could make a qualified guess based on a similar Omega calibre?

Typically with the Omega pocket watches that tends to be lots of? Basically just a lot of unknown people trying to identify the watch and they can't.

 

39 minutes ago, Endeavor said:

Perhaps in this list they didn't bother with the comma or the dot and describe it as a 355?

Wishful thinking as the 355 does not look like your pocket watch movement

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Omega_355

Here's one on eBay with an amusing description I will let you be amused by reading it. Although there is a claim that the 35.5 is the diameter of the movement I thought it was in line size not millimeters size? I guess you have to measure the dial side and see.

https://www.ebay.com/itm/383757342877

 

 

 

 

 

[nickelsilver]

You will encounter many watches with an unknown lift angle. The best thing to do is to learn to see the amplitude by looking at the balance arms. It's very easy with a 2 arm balance: from unwound, wind a tiny bit, just until the arms are coming right over the pallet fork, this is 90 degrees. Continue until the arms are switching places, this is 180 degrees. From there it's a matter of visualizing the further degrees; if it makes it to the arms directly over the pallet fork that's another 90 degrees, so you're at 270. Halfway there, another 45 degrees, so you're at 225. It's not too hard to divide a 90 degree quadrant into 4ths, you're in the realm of 20 degrees there (22.5).

 

I've found that the listed lift angle is off by several degrees or more just double checking the balance visually.

 

 

[Endeavor]

7 hours ago, Endeavor said:

Currently the movement is in parts and if in the meantime no info is found, I'll find the lift-angle via the 180 degrees amplitude timegrapher trick.

@nickelsilver Thank you for further explanation   Exactly this is what I meant with the "180 degrees amplitude timegrapher trick".

Perhaps it was just my illusion that Omega, everything they ever produced, was well documented by them; guess not

An illusion less, an experience wiser

Everybody, thank you for your time & help

 

 

[nickelsilver]

12 minutes ago, Endeavor said:

@nickelsilver Thank you for further explanation   Exactly this is what I meant with the "180 degrees amplitude timegrapher trick".

 

 

 

Ah I missed that you wrote that! So often folks seem to want to avoid looking at the amplitude...

 

When I was in school it was a transition time for timing machines, we had about half and half old paper tape machines with no indication of amplitude, and more modern Witschi with amplitude. So we were forced to learn to see it, and as mentioned above, you learn that the official lift angle isn't always right!

[JohnR725]

16 minutes ago, Endeavor said:

Perhaps it was just my illusion that Omega, everything they ever produced, was well documented by them; guess not

The only time documentation exists for us is if we need the documentation. Documentation for amplitude is only needed if the timing machines exist. Timing machines in the hands of everybody to measure amplitude is a relatively new thing.

Yes Omega does have a timing sheet of all of their calibers but how far back do they go? To give you a clue almost none of the watches in the timing sheet or 18,000 beats per hour don't know if their watches are actually numbered in order but it looks like 100 a is the lowest number in the old caliber section.Then looking at the revision section the see if I can figure out when the oldest version of this documentation came into existence it looks like 2006.

Then but don't worry vintage is included in the timing sheets this will give you a clue because it lists the watches by size. The clue here is I don't see any pocket watches.

 

 

 

[Endeavor]

Than, Omega doesn't seem to have inherited the "Deutsche Gründlichkeit"?

As far as I know Mercedes and BMW has a record of every car they ever build. Of course, I didn't expect Omega to have a record of the movement serial number, but as a minimum some info about the caliber number........ Hmmm , a bit disappointing, especially if I were to break a balance staff pivot; search for balance-staff number "unk". Didn't expect that from Omega

 

Edited February 4, 2023 by Endeavor

[JohnR725]

4 hours ago, Endeavor said:

I didn't expect Omega to have a record of the movement serial number,

I do know that some of the companies will look up the serial number of your watch but you have to give them a little money but let's Google and see what we find we find a link like this

https://www.vintagemasters.eu/omega-serial-numbers-check-and-verify/

Then you can go here but it's unhelpful as you need to go to an Omega boutique and they can look up your authenticity and yes I'm sure it's my costume little money

https://www.omegawatches.com/en-us/customer-service/certificates-and-extracts

Then it looks like they have some boutiques in Denmark.

https://www.omegawatches.com/en-us/store/country/denmark

4 hours ago, Endeavor said:

but as a minimum some info about the caliber number

I like I've said this before I've seen this come up with Omega's where any of the vintage pocket watches are doesn't seem to be any way to find anything out on them other than I think the first two numbers are size reference. Because typically only get parts listings if parts were available.

4 hours ago, Endeavor said:

search for balance-staff number

If you are searching for a balance staff it would be helpful to have the dimensions because often times you will find that they use the same balance staff for several different watches.

How do curiosity has looking in the bestfit book more Omega pocket watches and they have clocks listed a couple of those they don't actually say the word of pocket watch and they don't seem to have anything big enough to be a pocket watch.

So basically we just need of vintage material Log before bestfit

 

[Endeavor]

@JohnR725; Well according to your serial-number list it would put the movement production-date around 1922-1923, if the production serial numbers are reasonable linear (?). Even if they are not, around 1925-ish would be a reasonable estimate. About a 100 years old PW.

Both, main-plate and barrel-bridge do have the same serial-number;

Here a close up of the caliber-number and the main-plate measures indeed exact 35.5mm (and has banking pins too)

I like to add that Omega has done a very fine job in decorating the movement, I even wonder whether the main-plate and bridges are silver plated ??

 

Edited February 5, 2023 by Endeavor

[JohnR725]

I was thinking because the age isn't super vintage it may be best fit does have it listed. So what online and looked and they do have a 35.5 and it gives some part numbers so I went back to the bestfit book the civic you get dimensions for those part numbers and sort of. Then there's a minor mistake in the fingerprint system is says 33.5 but it's supposed to be 35.5 so if your fingerprint matches the 35.5 in the image then all the parts should be right. It looks like the 35.5 shares parts 39.5 which is helpful if you decide to break a pivot and you need a balance staff

I was thinking about it I went to the watch stem site and did get you stem dimensions that's another way to verify your watches just to measure the stem size and see if that corresponds. Of course it still is not going to get you technical data comes technical data didn't exist back then because there was no cheap relatively cheap timing machines.

 

 

Edited February 5, 2023 by JohnR725

[Endeavor]

@JohnR725: I don't hope I'll ever need it, but this is valuable information ! Thanks a lot for your detective work

[Endeavor]

@JohnR725@nickelsilver@VWatchie; the movement is back together and it runs very strong with straight lines.

I've done the 180≈185 degrees amplitude test and came to a (to me the lowest I've encountered) lift angle of 36 degrees !!

In the list which VWatchie referred to (above), the lowest lift-angle given among all those Omega movements is 38 degrees. Taking an operators error into account, I take over the 38 degrees lift-angle.

Fully wound, with a lift angle of 38 degrees, gives me 290 degrees amplitude horizontal and 250 vertical. This corresponds (≈ish) with the slo-mo video on my iPhone.

I guess, my initial assumption of a lift-angle of 50 degrees was "slightly" off

 

 

Edited February 6, 2023 by Endeavor

[VWatchie]

14 minutes ago, Endeavor said:

Fully wound, with a lift angle of 38 degrees, gives me 290 degrees amplitude horizontal and 250 vertical.

Fantastic!  And a very beautiful pocket watch!

I've never serviced a non-shock movement, but I have seen how to go about it. How fiddly was it taking the cap jewels out/in?

[Endeavor]

33 minutes ago, VWatchie said:

I've never serviced a non-shock movement, but I have seen how to go about it. How fiddly was it taking the cap jewels out/in?

In this case, you don't. On the balance side the regulator arm comes off (two tiny screws) together with the cap jewel disc. This allows you to clean & oil the cap-jewel. That's also the moment you peg the pivot-jewel. Best / safest is to remove the complete balance wheel so you work with the bridge only.

The main-plate cap-jewel sits in a disc, which can be removed by undoing 1x tiny screw. Again, clean & peg the pivot jewel, clean & oil the cap-jewel before replacing it.

 

 

[JohnR725]

6 hours ago, Endeavor said:

In the list which VWatchie referred to (above), the lowest lift-angle given among all those Omega movements is 38 degrees. Taking an operators error into account, I take over the 38 degrees lift-angle.

The problem with the typical lists are they only really represent the modern watches they don't represent the vintage pocket watches. So is always best to just figure out what it actually is rather than guessing. Although amusingly on this group somebody did find a pocket watch list on another group  and referenced it which I did find amusing because that was my list  that I posted on another group of pocket watches.. But I just now checked I don't have  any of the Omega pocket watches that I've done listed probably because I just wasn't worried about it..

Then if you like PDF lists here's one attached..

Lift angle Scope Schlagzahlen def 2-3.pdf

[Endeavor]

That's some interesting "pulse" information which I hadn't seen before, thank you for that !

Of course 2 degrees lift angle doesn't make a big difference on the timegrapher amplitude readings. The errors with this timegrapher-method (or perhaps the way I do it and with my Chinees Weishi 1000?) may easily exceed a 2 degrees accuracy.

Yesterday, with the movement just being serviced and assembled, the problem I noticed was that while doing the test, the amplitude was slowly on the rise. So it may already have been 190-195 degrees after watching the slo-mo video and making the timegrapher adjustments, which would bring the lift-angle for sure closer to the 36 degrees.

I will try again at a later date, but my current best guess is that it's somewhere around the 36 degrees

Thanks for your help

 

 

[JohnR725]

1 hour ago, Endeavor said:

The errors with this timegrapher-method (or perhaps the way I do it and with my Chinees Weishi 1000?) may easily exceed a 2 degrees accuracy.

The Chinese 1000 machine does a very nice job even compared to the witschi machine. But like any timing machine they can be influenced by things. The problem isn't so much the timing machine the problem is the watch it's mechanical and typically not perfect. So if your power fluctuations through the gear train that will ripple through to the balance wheel and cause variations.  Or if the signal is not nice and clean that that will cause issues.  Or even things like moving the watch around the balance wheel takes time to stabilize 10 speed less of a problem in a modern high frequency watch.

 

[VWatchie]

14 hours ago, JohnR725 said:

Then if you like PDF lists here's one attached..

Thank you very much @JohnR725! I've seen those "waves" many times in several videos but never understood what to look for, so very useful and interesting