Featured BEST WAY TO CLEAN GREEN TARNISH FROM WII NAVAL HAMILTON CHRONOMETER?

I found this at a local estate sale over the week-end - it is a Hamilton Chronometer Model 22 that were used by the US Navy during WWII.
I paid $400 - which looking at sold prices on eBay is less than 1/2 what they sell for (it was Sunday so everything left at estate sale was 1/2 price)
It is missing a first cover on inner box (they have 2 covers seller told me), but the gimbal? box is in a rare outer box that would be screwed into ship to hold clock steady/safe during rough seas (last photo)
I wound it & it has been keeping perfect time, but one side of the clock has white & green tarnish; what is the best way to remove it? (googling it shows everything from Magic Eraser to vinegar to toothpaste!)
Where is the serial number located? There is a number (14093) on the clock & on the bezel ring, but every serial number I've found has a letter (usually F) in it - or is that the serial number?
Thanks all, I appreciate the help


BOX/CASE THAT IS SCREWED INTO SHIP TO SECURE CLOCK - As rare as seller claims?

 

Beautiful piece.

It's difficult to tell from the photos, but it looks like there's an antique brass finish on it. There may have been a coating on top of that finish to protect it as unfinished brass would tarnish fairly quickly in those conditions. I would suspect that the white areas that you're seeing are issues with that outer coating/finish. If this is the case, the tarnish removal methods may not give you the results that you're looking for.

If you have a jeweler's loupe, maybe you will be able to tell if there's a finish and protective coating.

Good luck.

 

Oooh, I live with someone who would want that.

I am not telling him it's here.

 

Is there a method to fix it?

 

I don't the process, but surely can be done. Check the link below. The photos are kind of small so I can't tell if there were the white spots and whatnot on the piece. But they did an amazing job:

http://jlcrabtree.com/M22/M22.html

 

sabre123 is correct. All such scientific instruments were originally lacquered to protect the metal from corrosion. The fact that there is so much corrosion indicates the coating has broken down. Cleaning and repairing the damage is a major undertaking. You might be able to improve the appearance with a bit of mineral spirits on cotton swabs. Using any kind of polishing compound is more problematic, as you need to be sure to remove any polish residue. If left, it can cause further corrosion. Do not use vinegar. It is acidic, and if it gets down into the nooks and crannies you could be causing more trouble.
Ideally, the instrument would be disassembled, and each part carefully cleaned and re-lacquered.

 

The serial number would be on the movement itself

 

At the VERY BOTTOM of @sabre123's link, there's a link to contact the owner of that Chronometer that's just like yours......says "CONTACT ME" in the green strip at the very bottom......so contact him and ask what HE used to get the old lacquer off!!!!!!

 

In the jewelry trade we'd call that oxidation "the greenies". In this case it looks like "old green" i.e. inactive and not likely to do further damage. It won't hurt the piece to leave it alone if need be. If you want to get it off, I'd try ketchup. It's what you use on brass when there are rhinestones present. Dunking brass in vinegar will get rid of the greenies, but it puts paid to rhinestones. So... get some ketchup; those packet thingies from a fast food place will work fine if nothing else. Smear a good layer onto the green areas, let sit for a few hours, and wipe off with a damp cloth. The green ought to come with it. If not, you haven't lost anything but some fast food ketchup.

 

Very nice find ! Such great clocks !

 

Please! No ketchup!
With an object like this, you can't "dunk" it in anything, so getting anything like ketchup completely off of it would be difficult. Ketchup contains vinegar and tomatoes (of course), both of which are acidic. This is why it can remove some types of corrosion, but you risk doing more harm than good. It may look fine for awhile, but if you can't rinse it off completely the acid will eventually cause more corrosion.

 

...which is why it has to be completely removed, if leaving bad enough alone isn't an option. On "active" green, I start with a fingernail. If it's still wet it scrapes right off, no chemicals required. That may not be an option here.

 

I will try the mineral spirits if it doesn't sell right way (I was offered $500 today but I paid $400 & after eBay fees...s I countered with $600 & am waiting)
Than you all!
PS - the serial number is on the movement itself; doe that mean inside?
Finally - then what are the matching numbers on side & on the bezel ring?
Thanks again
PSS - Here is the leather firefighter's helmet (with the coolest shield I've ever seen!) & the fire extinguisher grenades I got at same estate sale (I also got a mint Singer 221 Featherweight with a lot of options but that sold the same night I listed it on eBay! I paid $500 for Singer and helmet so that means as of now the helmet only cost me $75!! )- the estate was that of a former Ft Lauderdale fireman; what a house and what a collection!)

 

What the heck - here is the Singer I also got there; I've bought & sold 3 or 4 of these before (Always finding them at thrift stores), but Never one as nice as this one! It was like they bought it & displayed it, never using it! Enjoy!

 

Are you planning to sell the sewing machine? @journeymagazine

 

It sold 4 hours after I posted it on eBay, I'm sorry.
Also - The Chronometer Just SOld!! I just accepted a $685 offer

 

Great eye, and great finds, journey! Congratulations on the profit so far, too.

 

Muchas gracias - wouldn't sell half of what I find without forum telling me what I've found!

 

Now that's what I call a score. That is a sweet helmet too. I'm not sure about those fire grenades; they may have to be sold locally because I don't think the USPS or shipping services want anything to do with the chemicals inside. The helmet could end up anywhere; I once shipped a fire helmet to Mexico. Fire collectors are everywhere.

 

Thanks. My latest find - I am on a roll!!
1992 Mountain Cycle San Andreas mountain bike: The first year model of the 1st bike to use inverted forks, hydraulic disc brakes & more - I found it at a local pawn shop yesterday for $60 and just accepted $700 for it on ebay!