Service: Bulova Accutron 2181

IMG_0049Some watches travel quite far before they land on my bench… This Accutron came all the way from Brazil. Victor contacted me a while ago and asked how to get his winding stem back in, and I tried my best to convince him not to attempt that himself. As he couldn’t find anyone locally, he sent the watch over to me.325-01

Under the microscope, you can see quite a bit of dirt on the pawl finger and index wheel, and that’s not a good thing. Time for a good clean.325-03

There is also dirt on the magnets of the fork.

IMG_0051The bottom plate looks clean enough. A simple, but effective construction.IMG_0055

Before removing the wheel bridge, you have to swing the index and pawl fingers away from the index wheel to avoid damage. The index wheel (the smallest wheel at the bottom) has 320 teeth! With the watch humming at 360 Hz, the index wheel completes 1 1/4 turn every second. The two jewelled fingers and the index wheel are the heart of the watch, and a technological feat that I admire to this very day.IMG_0068

As usual, there is a bit of corrosion under the centre wheel that drives the minute hand. This happens when condensation builds up in the watch, as it moves from the inside of the crystal through the dial hole straight down onto the plate.IMG_0057The tuning fork with the two coils and the electronic circuit. The wire of the coils is so thin that nobody out there has managed to re-wire one of the coils. We all depend on broken watches and old stock for coils, and one day, they will be all gone.IMG_0069

There are a fair amount of parts that have to be hand cleaned – the tuning fork, the index and pawl fingers, and the coils, as the cleaning machine would either destroy them or, in the case of the fork, load the magnets with lots of metal bits.IMG_0129

Most of the jewels have caps that can’t be removed. So after the cleaning machine, you have to check that no dirt is left in there, and that they are dry. Then, with a Bergeon oiler, you can lubricate the jewels.IMG_0133

With a new battery, the movement is humming again. I adjust the fingers under the microscope, and there really is no other way to do it properly. Bulova sold a stereo microscope with the standard kit for repairers.IMG_0135

The bottom plate is now ready for the dial and hands.IMG_0138

Back together and humming happily, I will need a good week to properly adjust the movement, and then it’s back to Brazil.

If you don’t have a tuning fork watch in your collection, go get one. For me, they are an essential part of watch history, and a technical marvel. And you can freak out people by telling them to hold it to their ear ๐Ÿ˜‰



13 thoughts on “Service: Bulova Accutron 2181

  1. Hi Christian.
    I purchased a Tissot tissonic (9162) yesterday and it worked all just fine during the day in my bag and until I got home to set the time of the watch.

    I set the time and now the watch is not working properly. The seconds hand moves and then stops after about 5-10 seconds and after a second it starts up again.

    Afterwards I read that the seconds hand wasnยดt supposed to spin during setting and that this was a sign of bad cleaning, and that the clutch that operates when you pull out the crown to allowe the hands to moved seperately from the watchtrain, didnยดt work.

    Do you think it is the index wheel that is broken or something else?
    How much do you think it would cost to get it fixed/replaced?

    Thank you for your time!

  2. Nice story with great pictures ๐Ÿ™‚ I’ve got a lot of accutrons and the Esa 9162 watches (speedsonic!) But my Omega megasonic F720 makes the weirdest sound, you’ve ever heard a Tie fighter?

    • My Tissonic (9162) makes a noise vaguely reminiscent of water rushing through a pipe ๐Ÿ˜‰

      I don’t know if Christian’s TimeGrapher has an option to capture the sound of a watch – or maybe an audio-out option – but the sound of some of the watches he repairs would be an interesting addition!

      Cant recall if this is one of my Accutrons or one I found somewhere;

      The sound has many layers… you can hear the hummmmmmm above all, but if you concentrate (and wearing earphones helps) you can start to pick up other sounds below it. I guess the acoustic signature of each movement – maybe even each watch – is unique ๐Ÿ˜‰

      • Thanks for the extra info. They are a lovely watch and the Bulova watches seem reasonable in cost. I have my eye on a few but the cost of post and import into the UK is making it prohibitive. I love some of the dials on these watches.

        How loud is the watch in reality?

        • You can hear it in a quiet room, and you won’t be able to sleep if you put it on your bedside table.
          During the day, you won’t be able to hear it unless you hold it against your ear.

          • Wow that is quite loud then.

            I don’t think I have come across one of these watches on any friend or relative. Which is surprising as I always enquire about watches people own that I know. There seems quite a few for sale though.
            Maybe I should just pay the excise.
            Is it a good idea to buy a few spares for these watches?

          • There are still people out there with spares, and I know a guy in Brighton that I pass work onto if I can’t get hold of the parts.

  3. Accutrons, IWC/Certina/Omega f300’s (ESA), Omega Speedsonics and last but not least the insane Omega f720 Megasonic. They should be on every collectors radar. In my opinion some of the greatest achievements of Swiss watchmaking before it all turned belly up in the late 70’s. (Yes Bulova is US based, however the Accutron was still a Swiss design from the start),
    True marvels of their time!

  4. Yes, everyone needs an Accutron… or 4 in my case, though 2 are non-working and 1 runs rather slooowly.

    This is a rather handsome one – wish mine still had its original bracelet!

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.