World War II Hamilton 37500 Cockpit Clock

Hamilton 37500 Front

The most rewarding projects in watchmaking are the ones you know are way beyond your depth, yet you try anyway (and most importantly succeed.) This Hamilton 37500 aircraft clock was undoubtedly the hardest and most complex piece I have worked on to date.

This clock was one of the most complicated pieces ever made for military aircraft and as such has a huge amount of parts. To avoid too much clutter and confusion, I decided to familiarize myself with the movement and find the problem by disassembling and reassembling it in segments.

The first goal was to replace the balance complete. I knew that this was not working because the balance staff was broken. Once that was done it ticked but stopped. Something more serious had to be going on so with that in mind I went about the rest of the process.

I first disassembled the mechanisms on the front. This included the civil date, date jumper, and the elapsed timer. Once I got all of these properly cleaned I oiled and reassembled them, I then wound up the movement, and although it ran it still stopped after a short time. The problem was not with the front.

I the set about taking the back mechanism, which was the chronograph. Here I noticed something was awry. There was way too much play in the fourth wheel (the gear that drives the second hand and by proxy the chronograph. A closer look revealed that the jewel that holds it had been shattered causing it to tilt and stop the movement.


Fortunately I had a harvester movement on hand. Although expensive, it was no where near as expensive as a service for one of these (almost $1200.) The harvested back plate was perfect and after swapping those out the movement worked perfectly.

Next I disassembled the entire clock. Ultrasonically cleaned everything and got it all back together. Although that only took two sentences to describe, it was way more work than the few words might suggest. After oiling and regulation I made sure that it runs properly through the full 8 day wind. A timing machine can only tell you half the story with large capacity mainsprings so it is always important (although time consuming) to let these clocks run through.

IMG_1912 IMG_1903

Pieces of WWII history like this are always a touch more rewarding than regular restores and come with an extra sense of pride. As does being able to restore such a complicated piece. That being said, it’s back to smaller pieces for a little while.

Hamilton 37500 Front Hamilton 37500 Angle

Hamilton 37500 Tilt Hamilton 37500 Back


Railroad Approved Hamilton Electric Caliber 505

Hamilton Electrics Feature

For anyone who has ever ventured into the repair of interesting watches they have undoubtedly been seduced by the idea of fixing a Hamilton Electric. I can say that there has never been a more frustrating and time-consuming restore than these. They are kind of like the Los Angeles of watches. They combine everything that is wrong with New York (Mechanical watches in this analogy) and Miami (Quartz) and roll it into one city. Their restore encompasses the delicacy of mechanical assembly with the frustration of dealing with electronics to create a watch that many have tried to repair but few have. I succeeded by luck and persistence alone. I do not advise trying this at home. If you do be prepared to face the most annoying piece you have ever dealt with.

All whining aside, this is an incredible and largely forgotten timepiece in the history of horology. Hamilton became the first company to replace the mainspring in wristwatches with their introduction of the Hamilton caliber 500. I tried one of these but quickly discovered that there is a good reason that there is only one person still capable of servicing them (he is also considered the foremost authority on their history.) Compared to the innovations that came shortly after like tuning fork movements and then quartz, the electric watch looks like an odd prop from an old sci-fi movie rather than a reliable timepiece. The truth is that this was the first and arguably most important step in the development of battery powered watches that would first cripple and then fundamentally change the Swiss watch industry.

After years of R&D development at Hamilton they introduced the electric watch in 1957 and coupled this technological breakthrough with fantastically avant-garde case designs for the time. They were produced for 12 years. The fact that they were made for a relatively short period of time coupled with the fact that they were made by only one company make them an absolute nightmare to track down extra parts for.

Used with permission of Rene Rondeau

Used with permission of Rene Rondeau

These two Railroad Approved models attracted me with their simplicity. The offset crown and the lightning bolt second hand very subtly indicate that something is different about these watches, but it is not apparent until you look under the hood (so to speak.) Their size is also very large for that era.

It took several re-assemblies and tweaks to get these things going strong, and now that they are I can safely say that I will never venture near one of these ever again but am very happy to have done so and added them to my work history.

Check out the video below of these two movements running!

P.S. – Should you need yours repaired I highly suggest contacting René Rondeau (the guy I refer to earlier as the one person capable of repairing caliber 500s) at He is THE authority on these pieces and the only one I know of capable of professionally restoring them.

Hamilton Electric Gold Side Hamilton Electric Stainless Side  Hamilton Electric Stainless Dial Hamilton Electric Stainless Front Hamilton Electric Gold Front

WWII Hamilton Military Caliber 987A

There is a certain amount of pride I get from being able to restore timepieces like this from WWII. This Hamilton Military 987A is a prime example of the durability of a well-designed and solidly built piece.

The more watches I get to restore, the more they seem to cement my personal restoration and vintage watch beliefs. If you are a stickler for a perfect case, then this restore isn’t for you. It is banged up, scratched, and battered, but in many ways that is what is so great about it. It also speaks to the craftsmanship of the case design that this piece went through so much and yet the movement, dial, and hands were nearly untouched. This watch has been through WWII worn on the wrist of a soldier and no re-plating or re-dialing should ever cover up a history like that.

This Hamilton is an early WWII design before the military demanded a few additional complications (See A-11, A-13, etc.) and came up with their own classification system. These specified types included the sweep-second hand rather than the sub-dial, and had a “hack” function meaning that when the crown was pulled out the movement stopped, allowing for precise time coordination. Hamilton did not participate in the manufacturing of the A-11s or any other A-specified military wristwatch but that didn’t stop them from delivering over 110,000 of these to the military.

That being said, I have never come across such a great example. I got this with a crystal so scratched and cloudy that I couldn’t even see through it. After it arrived, I removed the crystal to find gems of a dial and hands. The dial is a matte black with just the slightest hint of the Hamilton name (see the last picture of the dial out of the case.) With watches of this age, it is very rare to find a matching original “lume” meaning that the patina of the hands perfectly matches that of the dial. Over time, the lume paste dries and becomes incredibly brittle and flaky. All it takes is a little knock, or a bit of misplaced force while removing the hands and the paste turns to dust; forever ruining that perfectly matched patina.

The movement is an amazing contrast to the rugged condition of the exterior. As can be seen in the pictures, this movement was finished with the care and beauty that Hamilton was known for, and it is still in unbelievable shape. The 987A movement was perfect except for one thing: the balance was broken. I don’t know if vintage Hamiltons had incredibly weak balance staffs, or if I just happen to buy a ton with broken balances, but this is the most common problem I find when restoring old Hamiltons. After the full cleaning, inspection, assembly, and oiling, I installed a new balance complete and it sprung back to life in that magical way that makes all the labor worth it. A quick regulation to make sure it kept perfect time, and this piece was almost complete.

I feel like a leather band just would not look right on this watch. No one (at least in my mind) wears a fancy leather band on the battlefield, and so I needed to find something more fitting. Luckily I was able to track down one of the canvas bands commonly used at the time. The aesthetics just go together perfectly. The beige/green hue of the band meshes wonderfully with the patina on the hands and the dial.

All together this is a magnificently well-worn piece of WWII history that I was lucky enough to be able to restore.

Hamilton Military Feature Hamilton Military Side Hamilton Military Flat Hamilton Military Back Cover Hamilton Military Movement 2 Hamilton Military Movement Hamilton Military Dial

1953 Hamilton Lyndon CLD

The Hamilton Lyndon is a model that was only manufactured for 2 years. Given its serial number I would have to guess that it was a 1953 making this year its 60th birthday.

This watch came to me dull, not running, and with with an ill-fitting crystal, but cosmetically it was in good shape. After getting the movement back up and running (some old oil and dirt were holding it back) and fitting a new crystal I gave the case a polish and it was back to its former glory.

If you look closely at the dial you will see a little “cld” below the Hamilton name. Pronounced phonetically this sounds out “sealed” (or something close) and that was what this watch was meant to be. The CLD line was designed as one of the first watches designed specifically to be water and dust proof. They achieved this by using a new case design combined with new gaskets. While this is certainly no longer waterproof it is a beautiful and well-designed watch. The champagne dial is a variation I have never seen before, and I think it is a unique touch to an already distinguished piece.

Decoratively, the lugs set this watch apart and add a definitively deco feel to the watch. These wing-like steps are a unique stylistic addition that makes this watch a standout among other plainer vintage Hamiltons and the rest of the CLD line.

Built on the robust caliber 748 (one of my favorite Hamilton movements), this watch should easily run for another 60 years if cared for properly.

Hamilton Lyndon Left  Hamilton Lyndon Flat  Hamilton Caliber 748  Hamilton Lyndon Right

Hamilton Rodney

For most people an engraving on the back of a watch is a huge negative. For me it is the purest expression of provenance. It shows its story, in this case (pun intended) explicitly. It’s not as simple as “guy saw watch in window, guy bought watch, guy sold watch on eBay.” To me that’s boring. There are hundreds and in many cases thousands to tens of thousands of identical watches out there, it’s the engraving in the back that gives context and history to a piece, making it truly unique. This Hamilton Rodney I just finished has a great engraving on the back congratulating a man for 25 years of safe driving for the Michigan Bell Telephone Company. For me at least I find that to be an awesome addition to the story of a watch. Beyond the engraving, this has a sparkling and solidly built caliber 748 manual winding movement. The two-tone dial is great, and the light oxidation on it brings this vintage piece to life. The sharp lugs add a certain elegance to the aesthetics. Although it’s pretty old it shows almost no plate loss and is as shiny as the day it was engraved. It is slim, sparkling, has an interesting story behind it, and is now ready for its next owner to enjoy!

Side note: the big black spot on the picture of the engraving is not a hole; it’s my camera lens. I’m an amateur watchmaker not a photographer, so please cut me some slack from time to time on the photographing.