Never seen one of these before...

[JEC]

I came across this watch in a junk pile at my office. It was disassembled but complete, and the movement was free of rust or corrosion. It had been sitting in a drawer, with the movement exposed to the elements, for at least 15 years.

It's a 10k gold filled case with an American hallmark inside the case, the case is exceptionally well preserved. The plating is thick and undamaged. I gave it a light buff with a cape cod cloth and replaced the crystal, then had the movement overhauled. It runs great now, and it is in remarkable condition. I think the dial and hands are original too, if not a really good period redial. Since taking the photo I have replaced the crown with a period-correct Omega signed item.

What's unique is that it is a calibre 510, which was a small-run manual wind movement made in a series of less than 30k examples in the 50s. It looks similar to the 30mm calibres, but it's only 25mm diameter. 30mm calibres were made in the millions, to give you an idea of how rare these movements are. The case reference isn't on the records, I couldn't find any info on the model. The serial is from 1956-57.

The only downside is that it is a rather puny 32mm, but I have small wrists so it looks ok. I was looking for an interesting, thin dress watch and happened to stumble upon this one.

[jmsrolls]

Nice looking piece.

It's similar in style to my cal 442 bumper automatic from 1950:



This one is 36mm 18k RG and is my special occasion watch.

Fr. John†

[WJGESQ]

Originally Posted by jmsrolls

Nice looking piece.

It's similar in style to my cal 442 bumper automatic from 1950:



This one is 36mm 18k RG and is my special occasion watch.

Fr. John†

Bumper?

[Alcan]

Originally Posted by WJGESQ

Bumper?

Here ya go, a great thread on the bumper rotor movement:

http://forums.watchuseek.com/f20/wha...ent-41996.html