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!

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

  • 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…….

  • 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.


  • Yet another excellent piece of work.

    Thank you