Restoring A Rusted Scrap Automatic Chronograph – Valjoux 7750

In this video we take a big bunch of scrap valjoux (ETA) 7750 watch parts to see if we can build a working and reasonably accurate Automatic Chronograph wristwatch.

This project presented quite a few challenges, not least the amount of corrosion which needed to be dealt with. Can we get it working? If so., can it be accurate? Let’s see!


  1. Thanks for producing yet another fascinating video. I haven’t attempted a chronograph yet but this gives me the confidence to have a go.

  2. Love it Mark…
    Need to buy some of that rust remover!
    Loved changing the lower balance jewel setting upping the amplitude like that.
    Just spent the last few days building a Seiko 6138b from spare parts…….

  3. Like this a lot. I have a Valjoux 7750 in a watch I have which has a fault for my to identify and correct, namely a continuous running hour register. This video inspires me to have a go and shows what can be done with a “basket case” of bits.

    Thanks Mark.