Thanks for visiting my vintage Hamilton watch blog. I like to restore US-made Hamilton wrist watches back to their original glory and share my experiences with other enthusiasts. Use the "Search" space below if you know what model you're looking for. Feel free to leave polite comments or questions in the spaces provided. Also check out my "watches for sale" on my Etsy site - the link is on the right, just below.

Sunday, July 31, 2016

1966 Aqua-Date (Skindiver)

There has been one Hamilton watch that I've been on the hunt for a long time.  It's not an uncommon watch, in fact, it's easy to find.  However, they always sell for good money - typically well north of $500.

The model is the Hamilton Aqua-Date.  It was made from 1966 through 1962.  It's a "super compressor" model and specifically designed for scuba diving.

I think the Hamilton marketing folks were on the tight track with their media advertisement of the Aqua-Date but I'm not really sure why they thought wearing the watch on your goggles would be the best choice.

There are several different designs of "compressor" cases.  A super compressor typically has a robust screw down case back and two crowns.  One crown winds the watch or sets the time/date.  The other crown rotates a chapter ring inside the crystal so you can estimate the elapsed time.

The Aqua-Date can be found with the 17 jewel 694A movement inside or the 64A, depending on the year of the watch.  The transition was around 1970, based on my guesstimate.  The movements are largely the same with the exception of the 64A having four extra jewels in the automatic reversing wheels, bringing the total jewel count to 21.

As fate would have it, I was able to score what I thought was a decent-enough project watch.  The seller's photos were so-so, the watch wasn't very attractive and his description made no sense at all.  So I got a fairly decent deal of just south of $300.  That's a LOT for me - but as I said above, I've been looking for one for a long time.

Looking at the watch, the crystal is cracked along the side.  The dial is an orangish brown.  The hour markers and hands have been filled with black enamel - they should be lumed.  The proof for lume is the dial is marked T-Swiss-T.  The T stands for tritium luminous paint.  On the other hand, all the parts are present - so that was a positive.

It wasn't clear in the seller's photos or the description that the case back has a damaged section on the outside rim.   It's mostly cosmetic but I don't think this watch should be used for scuba diving in the future.  That's okay - I recommend you keep all vintage watches away from water, even if they are supposed to be "waterproof".  That's only true if all the seals are new and intact.

This watch has a 64A inside and it's very dirty.  The crown on the top is the time-setting / winding crown.  The other crown rotates the black elapsed-time ring inside the crystal.

You can see inside the case back the super compressor markings.  Notice the damaged section on the outside edge of the back.

Two retaining clips hold the movement to the inside of the movement ring.

This watch came to me from Columbia, in South America.  I guess balance cocks are in short supply down there, as this watch has a balance assembly from another movement.  Notice the pink color of it - and it's also missing the import code for Hamilton in the USA.  It doesn't really matter since it's tucked inside the case but I have a replacement for it nonetheless.

When I took the dial off I noticed an extra jewel floating around inside that got stuck under the set bridge (my tweezers are pointing at it).  All the required jewels are present and accounted for so this watch came with a spare, making it a 22 jewel 64A.

When I removed the crystal, the black elapsed-time ring came right out the front of the case.

What to do about the dial?  The hour markers should be lumed, not black, but the black doesn't look too bad even if it's a little sloppy.  The finish on the dial has crackled and is a mottled.  The hour hand is missing it's black section.  So I can either leave it all alone and just add black to the hour hand or I can try to redo the dial and hands with fresh lume.  The latter would require getting rid of the black paint on the hour markers,

The hour markers are held on with tiny rivets.  I could punch each rivet out and then boil the markers until the paint comes off.  That's a lot of work though... hmmm.... what to do?

I decided to soak the dial in my watch cleaning solution while I took the movement apart - maybe that would loosen up the black paint.  Unfortunately it turned out soaking loosened up the orange lacquer too.  Ugg - now I've got a splotchy dial!

Anyway, the movement gets fully disassembled and cleaned.

The running movement with a Hamilton balance cock is ready to go to the timer.  Hamilton's import code is HYL and you can see it near the crown wheel.

Uh oh, something is making a little extra noise inside.  I'll reclean the hairspring in case there's a piece of dust caught on it.

Ah, that's much better... running just a smidgen fast but that will do for now.

Well, I was able to remove all of the orange lacquer and black paint.  Miraculously I did not lose the printing on the dial too.  I sprayed it with a light coat of lacquer but got a little too much on so the finish on the dial isn't as good as I was hoping for - but at least I don't have to get the dial redone entirely.  I thought for sure this dial was a lost cause when the orange lacquer bubbled off.

Now I can relume the dial and hands.

The reassembled movement goes back into the case and it's ready to be sealed up by the case back.

Voila!  You have to look very closely to see the uneven lacquer finish I applied to the dial, including a tiny piece of lint that got stuck to it... oh well.  The crack in the crystal is now by the 6 and it's an obvious distraction.  This watch will look even better when I replace the crystal.  I also will order a nice strap for the watch... maybe a silicone strap or something "dive-like".

Regardless, I'm pretty happy with how it turned out and I think it looks better now that the dial and hands are re-lumed.


It turns out getting a proper crystal is a bit tricky for this watch.  The crystal has to have the proper diameter inside and out, depth and a white reflector ring.

There are a couple of options, one is a GS Diver Tite and another is a Tru-Seal.

The inside of diameter of the crystal has to be able to fit elapsed time ring surrounding the dial and allow it to spin when the crystal is installed but not lift away from the gear that turns the ring.  It looks like the Tru-seal is a better choice.

The crystal is pressed into place and when I first installed it there was too much friction holding the elapsed time ring.  I installed a very thin o-ring under the crystal and that offset it just enough to properly seat but also allow the ring to turn.

I couldn't find a rubber or silicone strap in the proper width.  I was able to find a shark skin strap though and although I'm not a fan of exotic skins from an environmental perspective, I made an exception since this is a dive watch and shark would seem to be a proper material.

This turned out to be a pretty nice project watch, don't you think?

Saturday, July 30, 2016

1964 Thin-o-matic T-409

Apparently "this was in" in the 1960's.  Although Hamilton's first automatics arrived on scene in 1954, automatics in general date back to the 1930s.  One thing they all have in common is the were thicker than manual winding grades, mainly because the auto-winding mechanism was an added layer on the back of the main watch mechanism.

The first Thin-o-matics in Hamilton's line up were introduced in 1959.  Initially, some Thin-o-matics use ETA movements with "thin" case designs but most of the time you'll find a Hamilton micro-rotor movement inside that was the product of Buren.  In fact, after a few years Hamilton acquired the Buren Watch Company, located in Switzerland.  Eventually, Hamilton moved all production to Buren's Swiss factory, but that wouldn't be for another 10 years.

There are over 70 different Thin-o-matic models, including the Dateline models with calendar complications.  So acquiring all of the Thin-o-matics models would be an impressive collecting feat.  Personally I find the micro-rotor movements to be a real bear to work on - so I haven't pursued them while there are other fish to find but occasionally I still go after interesting Thin-o-matic models.  One of my recent finds is a 1964 Thin-o-matic T409.

The T-409 is a one-year wonder and was only produced fro a single year.  It was a unique looking model with very interesting lugs that added visual interest to what would have been potentially just another round watch.

Although the T-409 was only made in 1964, you might confuse with the 1966 Dateline T-481.  It has a very similar case design - in fact, it might even be the same.  However, the T-581 has a date window  so it's very easy to identify.

The T-409 came in a 10K gold filled case and if you look closely at the catalog image, there is a gold chapter ring surrounding the dial.  Tucked inside is a Hamilton 17 jewel 620 movement.  The 620 is based on the Buren 1005 grade.

I've had my project watch for a couple of months while I worked up the courage to tackle another micro-rotor.  You might recall the February post I did on the 1959 T-401 - one of only two square automatics in Hamilton lineup.   That was my first attempt at a micro-rotor in several years.  They are VERY complicated calibers.

Looking at my project watch, it's in decent enough shape.  The bright lugs contrast well to the florentine engraved bezel.  The radial-finished dial is better than it appears in the photo.  The crystal has some smudges on it.

It wasn't until I started to do this write-up that I realized my watch doesn't have a golden chapter ring.  It has a plain gold reflector ring instead.  I suspect that a previous watchmaker couldn't find the correct crystal and made a swap.  I've seen other T-409's with a similar plane ring though - so maybe this is a factory-original set up.  Who knows?

The T-409 has a substantial case.  It's a large watch by vintage standards in addition to being thin, thanks to the flat back.

The 620 inside the case looks identical to the T-401's 663 movement.  Sorry for the slightly blurry photo - there are better one's below.  I'll have to look more carefully to see if I can find a difference between the 620 and the 663.

The inside of the one-piece case is fairly unrefined.  Normally the inside of the case is as nicely finished as the outside but not in this case (pun intended).

The dial-side of the main plate looks fairly typical.  The large ruby jewel on the upper left is part of an axle-less wheel that's involved in the winding mechanism.

I took a bunch of photos - but not as a step by step guide.  They were mostly for me - as an aid in putting this movement back together.  You'll see in a bit that there are a ton of parts inside this watch and the goal is to not have any left over when you put it back together.

Letting the mainspring down is a challenge on micro rotors so I my approach is to bull the balance and then carefully remove the pallet fork.  Without the pallet fork, the movement is free to unwind on it's own.  I also took off the oscillating weight, although the mechanism below it will take a while to work my way down to removing.

Next off is the middle of the autowinding mechanism, along with the ratchet wheel.  You can see how the motion of the oscillating weight is transmitted through various gears to the mainspring barrel.

Now the crown wheel has been removed and I'm deeper into the movement.  One more little plate to remove at 6:00 and the barrel can come out.

The bridge that covers the transmitting gear train parts can now come off.  In the shot below, you can see the opposite side of the axle that connects to the oscillating weight.  This little gear turns all the other wheels that winds the watch when you're wearing it.

Here's the gear train that is hidden below the bridge above when it's in place.  There's a little click with a long spring.  All of these parts need to be aligned in order to get that bridge back in place.  Did  I mention this is a tricky movement to reassemble?

Phew!  The easy part is finished - getting everything apart.

Everything is cleaned and dried.  Things are bright and shiny now.

Very carefully I put everything back on with lubrication in all the bearing surfaces.  I'll put the weight on last.  Next step is the balance and hopefully the watch will be running.

The watch is now ticking away.  If you look closely you might be able to see that there are no jewels in the balance cock.  I'll install them next.

There are two jewels on each end of the balance staff... a setting jewel and a cap jewel.  The two are held in place by a shock spring.

With the jewels lubricated and installed, the next stop is the watch timer.

Well, the watch is running but the beat rate of 19,800 isn't correct.  It's running a wee bit fast so I'll re-clean hairspring and try again.

The movement goes back onto the timer.... note the position of the regulator, near slow.

The watch is running with a proper beat rate but it's also a bit slow at -103 seconds per day.  The amplitude and beat error are good so just a tweak of the regulator is all that's needed.

Note the new position of the regulator - it doesn't take much to speed the watch up,

There - that will do nicely.

The oscillating weight goes back on and I'm now in the home stretch.  I just need to add the parts to the other side of the main plate, install the dial and hands and button it all up in the case.

Well, this watch was all the challenge I expected it to be.  I don't recommend trying to tackle a micro rotor unless you are very experienced with less complicated movements.  It requires a delicate and patient touch.  This watch turned out great though and I'm very happy with the results.  For a round watch, the T-409 is really sharp!

Tuesday, July 26, 2016

1963 Accumatic A-503

Back in April, 2016, I did a post on the 1959 Accumatic VIII and in December, 2013, I also featured the 1961 Accumatic VIII-B.  Those two watches look almost identical to each other.  They also look almost identical to the 1963 Accumatic A-503.  The main differences are the case designs and the movements inside.

The A-503 is the only one of the three to come in a one-piece case.  The other two have separable case backs.  The A-503 also uses the 17 jewel 689 movement, where the other two use earlier ETA-based grades.

In addition to the one-piece stainless steel case, the A-503 is also identifiable by the bracelet, assuming it has one, as the bracelet for the A-503 was different than the earlier VIII models.

I recently received an A-503 project watch along with it's original bracelet.  This bracelet is made by Admiral.  Overall the watch is in good shape.  The dial has toned a little but I think that's mostly the lacquer on the dial so it can't really be cleaned without losing the printing.  So I'll leave the dial and hands as they are but the rest can go into the spa.

The watch has a 689 movement but I'm not sure this is the original rotor.  The main difference between the 689 and 689A is the oscillating weight carrier covers the balance on the 689.  You can see that this watch has the balance exposed - so it might be a 689A carrier with a 689 weight.  It's not a big deal one way or the other but it's an interesting bit of trivia.

My photo of the disassembled movement was blurry so I'll skip to the reassembled movement ticking away nicely.  Notice this watch has the longer two-piece stem.  Watches with this movement sometimes use a shorter stem or a longer stem, depending on the case design.  That's a good thing to know if you need to replace the movement.  Since this watch appears to be ticking with good motion, tt's off to the timer to see how well it's running.

The beat error of 6.3ms is way too high, especially for a movement like this one, where the beat error is so easily adjusted.

The two parallel lines collapse closely together as the beat error approaches zero.  As you can see, I've reduced the error to near zero and sped the watch up slightly so it's running just a smidgen fast.  It will slow as everything settles back in.

This bracelet is a little short for my pillow shot so the links have opened up slightly.  You can also see the golden patina of the dial - it's nice and even so it's not a distraction and wouldn't warrant getting the dial refinished.