Shanghai Shoubiao Chang 7120 – Part 2: Reassembly

After having taken the watch apart, I put all the parts that can take cleaning fluid into the stuff for a couple of hours. Then all the parts are taken out and thoroughly dried. As I had a couple of days until I wanted to reassemble the watch, I put all the parts on top of a tissue into a dust-proof container ready for the day.

Today is the day, and I’m getting ready. Three types of oils in my oil tray – clock oil, watch oil and a super-fine watch oil for the escapement and pallets.

As the pallet fork can't go into the cleaning fluid, I start off by manually cleaning the pallets. I hold them with a piece of tissue paper and clean them with a sharpened stick of pegwood

Starting off with the centre wheel, I then put in the pallets. Before tightening the screw that holds the pallet cock, I make sure that the pallets move freely

The centre wheel has its own bridge. After that is screwed down, the other wheels go in

Now the wheel bridge goes in. Before screwing it down, I nudge all the wheels into their jewels and make sure that they all turn freely

When the wheel bridge is tightened, I apply oil to all the jewels in the bottom plate and in the bridges

The barrel bridge is put in. I put a couple of drops of oil into the spring barrel

The transmission wheel screw and the barrel screw look almost identical, but the transmission wheel screw tightens anti-clockwise. I check with a loupe which is which

The balance jewels have to be oiled before the balance goes in, as you can't oil them from the top. I carefully check that the balance wheel turns freely before tightening the screw of the balance cock

With the top plate complete, I turn the watch around and put in the crown and castle wheels

I put in the wheels for the time adjustment, oil them and put the cover into place

Now the date wheel is put into place, and the pawl without the pawl spring is put into position

The pawl spring goes in after the date wheel cover is screwed down

I polish and clean the hands by lightly rubbing them over a piece of paper

To put the hands on, I manually adjust the watch until the date wheel changes date. Then I put the hour hand to midnight. Afterwards, I forward the watch to 4, and then put the minute hand on, making sure that the hour hand is exactly on the hour. After that, I check the date jump again and make sure it's exactly at 12

The movement goes back into the cleaned case

The back is screwed back into place

And our watch is ticking nicely again

This is a nice little watch and I'm quite envious of Joris!

Before sending it back to the Netherlands, I will leave it on my bench for a day or two just to make sure everything is all right.

9 thoughts on “Shanghai Shoubiao Chang 7120 – Part 2: Reassembly

  1. Hi Christian, this particular blog inspired me to buy one of these watches…£15 on eBay incl P&P! New old stock! There are 3 left, although a search on eBay doesn’t bring them up on the page….very strange. There are also 24mm case diameter, ladies versions available for £14; might be an ideal mechanical watch for your daughter. PM me if you want the link.

      • No problem.

        I’m tempted to buy one of the ladies watches for one of my two youngest daughters (7 & 9). There is even a second metal dust cover over the 17j movement behind the screwed case-back; unusual for a utility watch.

  2. I really love these watch strip dons and rebuilds. Thanks for taking the trouble to publish them. I have a watch with this movement in, though mine is an automatic so it will at the very least have the extra parts for winding in it. I think the rest of my watch is just the same as this from my inexpert and cursory inspection. It keeps remarkably good time, surprisingly because it cost next to nothing and came from Hong Kong.

  3. That watch has made quite a journey in its short lifetime so far. From the factory to the seller, to me in Canada, then to Joris in the Netherlands, to you and back to Joris. I’m so happy you were able to revive it, it was a give away inspired by the generosity of another watch enthusiast. My daughter chose Joris to receive it because of his touching account of life with his sister. I wish him many years with this watch and thanks to you for servicing it.
    David

    • This watch is getting quite a story – and a very typical internet story. We wouldn’t have done this 20 years ago 😉

      Nice to see such a great amount of goodwill all around. May Joris wear is in good health!

      Christian

  4. Pingback: Reassembly: Shanghai Watch Factory 7120

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