Servicing cal 710

[Jfree]

Hello,
I am a hobbyist watch repairer and am servicing my Dad's old 6022 with a cal 710 movement, that he won in a bingo game in 1952 while stationed in the middle of the pacific ocean on Eniwetok when he was 21 years old. I have been studying horology for about a year and serviced a few watches including a vintage Omega 2179 with a cal 30T2SC, very similar to this cal 710. I have a few questions and would really appreciate any help. I have taken everything apart and getting ready for some repairs that are blatant, before cleaning etc.

1. Past service person broke a case screw off on the plate. Should I extract it with a screw extractor or soak the main plate in alum and dissolve the broken screw. A bit concerned that the plate could be damaged soaking it.

2. Stem and crown were easily removed but stem is wiggly in crown as if the outer diameter of the stem threads are too small for the threads on the crown. It was screwed together but I could tip the crown from side to side on the end of the stem. I have successfully removed the stem from the crown. (photo attached. Am I right to assume that I would need a crown gauge such as the bergeon 6740 gauge? Does any one have a rolex part number for this or aftermarket supplier number for cal 710 stem?

That's it for now. I am sure that I will have more questions when it comes to adjusting the watch. The timegrapher readings before taking it apart were a bit crazy even after demagnetizing.

Thanks,
Jeffrey

[Valenciawatchrepair]

Cool story to go along with watch.

As for your concerns.

1 - I'd probably take a look at the screw from the other side. I don't recall the 710 from memory, but it's possible you might be able to spin the screw out from that side. Maybe not. I just had a different watch with the same issue. I was actually able to use Rodico and form it into a sharp point and actually grip the broken screw and spin it out. That was a relief. lol

2 - You don't NEED the crown gauge. I mean, I have that exact gauge and I rarely use it. I would doubt the thread size is wrong on the stem. Not a model you'd see with other stem tap sizes available. I can't say I've ever seen a crown wear while screwed in, especially to the point it wobbled in the threads.

The tiniest bit of paper with Loctite applied will actually allow you to securely fasten it. Otherwise you'd need a replacement.

eBay is a good place to look as well - https://www.ebay.com/sch/i.html?_fro...crown&_sacat=0

[nboyer]

If you go the alum route, be absolutely certain that you have removed ALL steel parts, as they will be partially or fully dissolved. The mainplate is likely brass or plated brass and should be unaffected by the alum. I used alum once on a broken screw in a Hamilton pocket watch, worked a charm. I left the part in alum over night. The broken screw turned black and was semi dissolved where I could push the broken bits through with a needle and then cleaned up with a tap.

On a side note, be careful handling the watch hands. The lume is likely radium, be aware of any radium dust on the dial, some nasty stuff if you've not read about it. Cheers! -Norm

[Jfree]

Thanks