How to identify chrono cases?

DManzaluni · Apr 27, 2016

I just picked up a few chrono cases, one with a flat bezel, 38mm across, dial about 34mm, movement 31mm across. movement height seems to e about 3mm, with an additional 1mm to accommodate the dial

the other one has a normal bezel, the case is 35mm , movement is 33mm across movement possibly 4.25mm high.

Neither are marked with anything other than a serial number.

Is there any way of identifying what movement was supposed to go in either of these please?

Amadeus · Dec 2, 2016

Hi, are you sure your movement height measures are correct? There's no way a chrono movement would have just 3mm of height. Revise your height measures.

The flat bezel case ( 34mm x 31mm x 3mm) number 709 is a Breitling case and the correct movement for it is a Venus 175 like this one:

As to the regular bezel case I can't tell you for sure until you tell me the correct height dimensions.

DManzaluni · Apr 27, 2017

Amadeus
Hi, are you sure your movement height measures are correct? There's no way a chrono movement would have just 3mm of height. Revise your height measures.

The flat bezel case ( 34mm x 31mm x 3mm) number 709 is a Breitling case and the correct movement for it is a Venus 175 like this one:

As to the regular bezel case I can't tell you for sure until you tell me the correct height dimensions.

Sorry for delay on this Amadeus but i have been trying to figure out how to measure height inside a case properly. The height of the Venus 175 one seems to be a shade over 5 mm between the base of the case and the bottom of the plate above which the dial goes. Now that you point me in the right direction, I see Ranfft says 5.7mm and I can imagine the plate on which the dial sits is .6mm high so my measurements cannot be as bad as I think

The other case takes a movement which is about 5 mm high. Can you tell what movement this takes or does the shape of the parts behind the pushers help?

Not sure why my earlier measurements were so bad but thanks for your help so far

DM

Amadeus · Apr 27, 2017

Hi, could you send me pictures from different sides (including the inside) of the first case (the one with the 375131 serial number) if possible without the glass and bezel, so I can try to figure out which movement could fit the case.
From a preliminary guess this could be a possible movement that could fit that case:

DManzaluni · Apr 28, 2017

Thank you again for your assistance, do these photos help?

Amadeus · Apr 28, 2017

As I thought that case seems to be for either a R Valjoux 22 or a Valjoux 23 movement. My recommendation would be to try and get any of those movements and try them on the case, if you're having problems doing it, try to take it to your local watchmaker.

DManzaluni · Apr 29, 2017

Well thank you for putting me out of my misery on that at last, but the movement is so nice that I cant see myself ever picking one up for any sort of reasonable price! Even one without stem and pushers.

Maybe I should concentrate on the Venus 175 for the moment.

Amadeus · Apr 29, 2017

No problem, I'm happy to help.

DManzaluni · May 10, 2017

Actually it shouldn't be difficult to identify exactly which movement from the Valjoux 22 family this case is: Which of them was 33mm across the movement and had an equidistant 7mm between the centre of the crown and the start of both pushers?

Kwijibo · Jun 2, 2017

they look like pre war watches (second of course). most of theses chronos were fitted with venus movements. An other thing I notice is some of yours a plated and others seem to be made of solid steel which makes a noticeable difference. The harder thing in not to find a movement but a fitting dial.

Modest_Proposal · Jun 10, 2017

Honestly - unless these cases are sentimental to you... this effort is not worth it. This is one of those rabbit hole projects.

Best to simply buy a whole watch than built one from scratch. Considerably less work and considerably more valuable to other collectors, should you sell.