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, March 30, 2014

1955 Automatic K-403

There are 59 different Automatic K-XXX models from the 1950's.  Even more if you consider all the different dial variations, colors, etc.  I have a long way to go if I plan to detail them all on this blog.  Of course, some of them are solid 18K and 14K gold so I will have to dig deep if I ever see those versions for sale.  The gold filled and stainless steel examples are much more in line with my watch allowance.

A good example of the more affordable Automatic K-series watches is the 1955 Automatic K-403.  It was produced for three years.

The K-403 comes in a 10K yellow gold filled case.  Only a white dial with yellow embossed numerals and markers.  The hands are luminous to match the luminous  dots applied to the markers and numbers on the dial.

Behind the dial is a 17 jewel, Swiss-made Hamilton 661 automatic movement - the typical movement in almost all K-series watches from the 1950's.

My K-403 project watch was in decent shape but in need of some care, for sure.  You can see the upper left lug is bent inward and the case has it's fair share of bumps and bruises.  The movement is not running.

I like when the case back is the same material as the bezel.  I don't mind stainless steel backs though - I just prefer when the case back is gold filled to match the front.  A little gentle polishing will make this watch shine brightly.  You can see that a metal bracelet has taken it's toll on the lugs and worn slight grooves into them.

If you follow my blog, you've seen me overhaul lots of 661 movements.  If you've got an eye for detail, you might notice the ratchet wheel screw is missing.  This is the screw that holds the large ratchet wheel into the mainspring barrel arbor.  That screw keeps the ratchet wheel from popping off and releasing all of the mainspring tension.  I'll need to get a replacement in order to complete the overhaul - you wouldn't want to risk running the watch without this screw.

The rotor is easily removed by sliding the toggle switch near the center to the left.  Then the rotor will slip off when it is rotated to the right spot.  Taking the rotor off makes it a little easier to handle the movement when taking it out.

In the shot below, you can see the rotor off to the side and only the rotor carrier is left on the movement.

Well, here's a pleasant surprise!  The ratchet wheel screw in upside down and next to the balance wheel (just left of center).  That would explain why the watch wasn't running - it's the proverbial "wrench in the works" and kept the balance from turning.  That's a good bit of luck!

The dial is a quality refinish.  The main tell is the word "Automatic" should be slightly curved.  But that's a very minor detail and the rest of the dial details look very nice.

Everything is now cleaned and set out to dry before being reassembled.  I think the hardest part of reassembling a 661 is getting the rotor carrier back into place.  You need to line up four different pivots and there is very little room to fiddle with them and get them in place.

The watch is now running vigorously and tweaking the regulator eventually got it to maintain a nice beat rate.

Putting the hands back on requires looking at them from this angle.  You install them at 12:00 so you know they're synced but you also need to make sure they are parallel to each other and to the dial as well.  As long as they are parallel they won't run into anything and stop the watch.  I haven't put the second hand on yet but it will go on top in the same fashion.

The last step is to put the newly serviced movement back into the case.  Then the rotor can go back on before buttoning it all back up.

Here's the finished project watch, all polished  and looking great.  I was able to bend the lugs back into proper position.  I can't do much about the wear to the lugs but I think the watch looks great - it is over 50 years old, after all.


  1. I have what appears to be a K-403 with the same lugs and size, but with a black dial and a different number configuration which includes gold 2,4 8, 10, and 12 Arabic numbers and teardrop hashmarks at the other numbers. There is also a gold dotted track between "Hamilton" at the upper part of the dial and "Automatic" on the lower part and the hour numbers or hashmarks. Was this a manufactured model or is this an altered re-dial?

    1. It could be a K-401 or a K-402. They are very similar and the dials are as you describe. The shape of the numbers is important.


      Or you could have a K-401, K-402 or even K-453 dial in a K-403 case.

  2. Hello from Montreal.

    I found an almost identical (if not identical) watch at a garage sale this weekend. I wound it up, set the time, and walked away for an hour or so. When I came back, it had kept the time perfectly, so I figured it was worth the $15 the seller was asking.

    It really is the same watch, I think, right down to the lugs. The only difference from yours is the word "AUTOMATIC" which is curved, presumably in the original way.

    I removed the case back and found that the rotor lifted out without sliding the release toggle. The inside of the case back has many wear lines from the spinning rotor, which I imagine is not how it's supposed to look.

    If I may ask a question or two, Without seeing this watch in the flesh, so to speak, do you have a theory as to why the rotor was disconnected from the rest of the movement?

    And do you have a rough idea what an horologist might charge to fix it, assuming the parts (if any are needed) are available?

    Thanks very much,


    1. $110-$150 wouldn't be out of line. Of course, I'm sure you could find someone to charge you a lot more.

      I couldn't tell you why the rotor came off... maybe it's broken or maybe it just came off.