To compare the 4992B 24 and 12 hour . . .

The 24 Hour is 1945-48 vintage S/N 4C110078, and the 12 hour (conversion Lindell?) is c.a. 1943, S/N 4C69651.

The movements look (to our un-trained eyes) to be identical . . .

The 4992B 24 Hour watch "Hacks" . . .

Now given (that we can all guess or know) the only changes to a 24 hr to make it 12 would be to replace the 2 24 hour hand gears with 12 hour "922" type gears, and put on a 12 hour dial . . . then WHY is the 12 hour "conversion not a "Hacking" watch?

Perhaps the hack spring was removed by a watchmaker because it was too much trouble to adjust after cleaning?

Norman

I have just bought a 24 hour and 12 hour 4992B, though as yet only the 12 Hour has arrived. It is very nice, very acurate and is has a hack lever installed, but not working.

I can see the 'stop wire', and some very minor movement of same when the stem is moved. However the hack is not functioning.

Does anyone have any ideas why? I guess there must be some thign wrong in the stem, clutch, lever area.

Tony

Hi David. In the photo of the backs, I am not seeing any of the standard military markings. Are they just worn down or are they absent. If they are absent it would seem that as part of the later conversion that either the back was ground down to remove them, which is a shame as the markings are so important these days, or the back or entire case are replacements as well.

My 12 hour 4992B does not have gov markings on the back and has never had them. My guess is that these were either not made to service government contracts, no US Gov engraving on the movement either, or they were civilianised.

As mentioned above, the hack lever is evident but not working.

Tony

Movement

Hello, this just arrived. It is a really nice Hamilton 4992B.

I posted it here because I thought all 4992B watches were built under military contract, but there is no "US Gov" engraving within. The serial number puts it somewhere near 1942 I think.

The watch is very accurate and the runs well and only has one minor clutch. The Hack function is not working. You can see the hack wire, but it is doing nothing.

This dial looks like a silver metallic type paint. I have no reason to think this is anything but genuine but though out this forum I have yet to see or hear about anything other than a Black or White Dial.

Any information you may be able to provide would be most welcome particularly about the dial and getting the hack function working again.

Tony


Movement Zoom

Case Back

or not inscribed as to uses and disposed of unmarked at wars end

Well, my 24 hour watch arrived and as described by the seller the balance staff is US. I have ordered a replacement, though I have also been offered a complete balance. I am uncertain of my ability to replace the staff and poise it with put breaking the balance.

To confirm that this was all that was wrong I swapped the entire balance, including the balance bridge from my 12 hour. Please to report it runs perfectly.

The upside though it that my wife loves and now wants a 24 hour watch of her own. This is some form of affirmation!

Next problem is to find one at a price she/we can afford. Surprising many current sellers on the "bay" site wont ship outside the USA go figure. Anyone have a nice 24 hour 4992B then I have a good home for one.

Cheers, Tony