Movement identification - olma deluxe

[Deggsie]

Hello all. It’s been a little while since I joined here and would just like to say how very useful I find the site for information and mostly just a pleasure to read

I recently received a vintage olma with 17 jewels, but unfortunately the staff pivots are worn away and I need to either replace the staff, or, the balance wheel assembly complete with hair spring.   The trouble I’m having is identifying the movement.  Having removed the balance cock the numbers 727 can be seen, but no indication of the movement manufacturer.  I have attached some photos and would be most grateful if anybody could please advise where i might find out the exact movement so that I can obtain a spare balance assembly.  

Thanks in advance and seasons greetings to you all. Regards Eggsy 

[wls1971]

In order to establish who manufactured old movements it is almost essential (few manufactures had unique bridge layouts)to remove the hands and dial so that the setting parts of the watch can be seen they are unique to each individual manufacturer and can provide positive identification. Most part catalogues use  pictures of these parts to identify movement maker, books such as Bestfit , Flume, Paulsons and Catalogue Official.

In watches from the 1920's to around the 1940's most manufacturers used almost identical bridge layouts making it very hard to establish calibre and maker.

Another useful thing to know would be the approx measurements of the movement.

 

[Deggsie]

Thank you WLS for your very useful response. I remove the hands and dial, take some photos of the keyless works etc and report back to you all.  Once again thanks. Regards, Eggsy

[clockboy]

This I found difficult to find a few pics of the keyless side might be helpful as I can then peruse my "Bestfit" books. 

It might be a modified ETA 727 as this calibre it is real close but not exact.

[rogart63]

I say ETA 727 with a different bridge layout.  Not that uncommon. 

[Deggsie]

Thanks everyone for you replies. I have now had opportunity to remove the hands and dial, and take a few photos of the keyless works along side a ruler just to give an idea of scale.  Hope this is of use and looking forward to finding out more about this little movement . Kind regards to all, Eggsy

[Deggsie]

Well it seem unfortunately that my photos won’t upload.  I’ll try again later guys.  

[Deggsie]

If it’s an eta 727, is the balance wheel assembly readily available or do I need to fit a new staff?

[Deggsie]

[Deggsie]

Not sure what’s preventing me uploading photos.  I’ll try later.  Thanks again for your help this far, I also now think it’s an eta 727. Kind regards. Deggsy

[rogart63]

Can't see there is a balance on Cousinsuk but there is a balance staff. Not on ebay either. I repaired a ETA 717 some months  ago. Had to find a donor movement to get a good balance. According to http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&ETA_717  that is the same as ETA 727 

 

[clockboy]

4 hours ago, Deggsy said:

If it’s an eta 727, is the balance wheel assembly readily available or do I need to fit a new staff?

Yo need to identify the movement first before searching for parts.

[wls1971]

As clockboy as stated double check you are dealing with a eta 727 I've lost count of the times I have ordered parts wrongly before I had a good selection of reference books.

Cousins lists a balance complete for a eta 717 looking on Ranfft Eta 717 through to 719 , 724, 726 ,through to 729 all have the same specs as regard basic architecture, and staffs are the same, mainsprings, and stems are the same I would think that the 717 balance complete would fit it is listed at £20.74 on the web site under Eta 717.

Do a bit of research it may be suitable.

[Deggsie]

Thanks gents.  You have been most helpful and as soon as I can get the photos on here I will.  Having looked at the eta 727 on ranfft I believe it to be a good match.  I don't have the tools to swap out the staff alone, so will need a balance staff assembly with hair spring. Kind regards Eggsy

[StuartBaker104]

The most common problem with uploading photos is that the file size is too large. Don’t know what the limit is but it’s less than 2Mb.

[Deggsie]

Edited December 18, 2017 by Deggsie
Thanks Stuart. File was too large

[clockboy]

I have  cross referenced with my "Bestfit" and the setting lever for the 717 is slightly different. According to "Bestfit" the 725 is compatible with the 717 also a variant of these calibers is some were fitted with a sweep seconds hand. This might account for the slight differences. 

[rogart63]

Setting lever looks like it could be a ETA 717 . Just like the one i have. So think it's a ETA 727 as they are the same. The little plate over the hour wheel is more Eterna looking . 

[Deggsie]

Hello all.  First thanks for your work in referencing with books etc to try and ascertain the movement number.  I notice that If you look about 17mm up and slightly left of the centre line, you can see a shallow recess.  This is where ‘ETA’ is usually marked.  For some reason the brand marking has been machined off.  I’m hedging my bets on this movement being an ETA 727.   Even if it is a 721, the balance assembly is the same part number.  Thank you all again for your help and guidance, I would not have got this far alone  and I hope you have a very merry Christmas. Regards Eggsy