Question for Archer

[CHIP]

Roger posted an article on ETA scaling down and companies like Selita stepping up their production.
I also noticed that you mentioned that some Oris watches are now using Selita, and I know that TAG models have recently been popping up with Selita movements.

My Muhle is also a Selita powered watch.

I have done some research and I now know a bit about the brand but I wanted to see if you have worked on any Selita powered watches and if yes, what is your take on their movements?

Thank you in advance Archer.

[Archer]

I don't see as many Sellita movements as I do ETA based watches, but I have worked on a few. Mostly the Cal. SW200, which is quite similar to the ETA 2824-2. I may have serviced a 220-1, but none of the 2892 clones (SW300)or the 7750 chronograph clone (SW500) as yet.

My general impressions after working a few are that they are not quite as accurate as the ETA based versions generally (although individual watches can be quite accurate). This may also be a factor of the brand, as some brands just slap it in the case, and others take the time to adjust and regulate more.

Early on the SW200 and SW220 had issues with broken teeth on the ratchet wheel, as shown here:



Now Sellita made a change to several parts in the automatic winding system to resolve this issue, and they used to have a technical guide on their web site that explained this in detail - here is a screen shot I took back at that time:



Note that it's clear they changed the profile of the teeth to beef them up, in order to avoid the teeth shearing off, and this became the SW200-1. This required the ratchet wheel to be changed plus a few other parts in the automatic, as tooth profiles changed on several parts and you can't mix them up.

Unfortunately they have since removed all this information from the technical guides they post on their site, so IMO this is a bad move as it does not help the watchmaker who is repairing the watches, and it's more likely to end up with someone only replacing 1 part when they should replace several.

Now the observant among you will note that the first picture above shows broken teeth, yet this is an SW200-1 movement, so this problem was supposed to have been solved, but certainly not on this watch. I'm not saying I never see broken teeth on an ETA 2824-2 in this location, but it's quite rare.

Now again my impressions are based on only servicing a few movements, so I can't apply these to all Sellita movements, as the numbers that have crossed my bench are just too small to say for certain what they are like long term. Time will give us a better impression of the performance and longevity, but for certain they have not been without issues early on at least.

Hope this helps.

Cheers, Al

[CHIP]

Thank you Archer for the informative post.

In regards to my Muhle...

According to my research, watchmakers are not allowed to slap Glashutte on the dial unless at least 50% of the value of the movement comes from Glashutte.

Muhle changes the plate (3/4 plate... does that sound right?), adds a woodpecker regulator, an extra jewel, a custom rotor and heat blued screws and they add the Glashutte specific finish to it, which I can never manage to capture in photos. (it's that cool looking spiral like finish)

So far this has been an accurate watch but the power reserve is not too great, I would say around 34 to 36 hours. Give or take.


Photos from the web...

[Archer]

Okay so this is the SW500, which is one I have not worked on yet. Looks like they have changed the train bridge (the 3/4 plate) and added a cap jewel to the escape wheel, and I see a portion of a new spring in the shot of the plate you posted, so it looks like they upgrade it enough to meet the 50% requirement you mentioned.

I'm a bit surprised that the power reserve is so low. For the 7750, which this is "based" on, the stated power reserve by many brands is 44 hours. However if you look at the ETA technical guides, the reserve is stated at 48 hours (brands are just lazy with their documentation). I service quite a lot of the 7750's and it's not unusual for then to run well into the 50 hour time frame. I think I've even had one or two that ran as long as 55 hours on a full wind.

The Sellita technical guide for the SW500 calls for a 48 hour power reserve, just like the 7750 does. What does the maker claim for power reserve?

Cheers, Al

[CHIP]

Looks like I made a few mistakes in my post.

I did not even realized that at least one of the photos I posted depicts a chronograph model, which is not what I have.

Mine is just a three handed model. Can't believe I missed those pushers even though they were staring at me in the face!

[katgirl]

Chip,

My Frederique Constant has a Sellita SW200 movement, which is an ETA 2824 clone, with an extra jewel. Like your new watch, it is Swiss made, hand assembled at the factory in Geneve, and the movement decorated and regulated by FC. Mine has a gold plated rotor, visible through the small window on the case back. It's called an FC-303 movement. Power reserve is listed as 38 hrs. I'll do an accuracy check and a power reserve check, and report back.

KAT

[Archer]

Jul 16, 2013 6:47:09 GMT -6 CHIP said:

Looks like I made a few mistakes in my post.

I did not even realized that at least one of the photos I posted depicts a chronograph model, which is not what I have.

Mine is just a three handed model. Can't believe I missed those pushers even though they were staring at me in the face!

Well looking at the photos again, at least 1/2 of them are for sure of a chronograph.  In the first shot you can actually see "7750" marked on the plate of the movement near the right side if you look closely, so that one does not appear to have a Sellita movement on closer inspection.

So the Sellita SW200 would have the same power reserve as the ETA 2824-2, which is stated at 38 hours.  They will often run a tad longer than that, but 41 hours is about the max I see on those after I service one.

If it's an SW300, then it would be 48 hours, the same as the ETA 2892 that the movement is based on.  Again I regularly see for example Omega Cal. 1120's (2892 base) run for over 50 hours on a full wind.

Cheers, Al

[CHIP]

www.muehle-glashuette.de/en/wristwatches/manufacturing-technology/the-technology-of-our-movements.html

Here is a link that talks about it more.