ETA Part Number System?

[Hoe]

Hi there

A rookie question:

I am working on the two vintage ETA movements 2783 and 2873 and will need spare parts for the automatic winding assemblies. While searching for these parts I came across obviously different ones which have the same part number.

Furthermore, some ETA parts are interchangeable between ETA movements.

How do I determine which part number I really need, how does ETA’s part number system work?

So far I am going for photos rather than numbers when looking for parts on Ebay.

Best wishes

[JohnR725]

a problem with this particular numbering system is that the numbers represent a part. Such as a stem is referred to part number 401. But part 401 without the movement number could refer to literally hundreds of different stems. So it's kind of a two-part system the number as opposed to the word stem bike 401 and then the movement number. Otherwise ordering a 401 all by itself it isn't going to fit.

helpful when looking for parts is the third link where you can see the differences of the watches you're looking for they appear to be in the same family. Then the first in the second plank are the parts. If you click on the part number in each of the listings it give you the cross reference the parts.

 

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=ETA_2773

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=ETA_2783

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&ETA_2783

[HSL]

I think those numbers refers to the system EBAUCHES SA tried to introduce a while ago. ETA has change their system a bit and do not always use these reference numbers nowadays.
The older tech sheets still do so I attach an old document describing the different parts and their referens number.

Dictionnaire Technologique-EBAUCHES SA.pdf
 

[HSL]

To get which parts are interchangeble between the different caliber would be a mamuth book.
So insted one can buy access to an database provided by BestFit.
Here you can see the actual part number and which calibers share this part.

Access to the database is sold by Esslinger
https://www.esslinger.com/matsys-online-from-bestfit-lifetime-membership-watch-parts-lookup-software/

This is the Caliber Search

And the Interchangable list


 

[Nucejoe]

Dose this database or any other, also provide tech specification for parts, like CGS for HS? 

TIA

[HSL]

13 minutes ago, Nucejoe said:

Dose this database or any other, also provide tech specification for parts, like CGS for HS? 

No unfortunately not, to get the CGS numbers one still have to meassure the hairspring or use a bunch of old lists.