This is the bobbin winder from Maria's Jones Family CS machine before I started attacking it with the metal polish. The easiest way to clean it was to unscrew it from the machine.
On close inspection you can see the black oily grime clinging around the screws. After scraping the worst off with a wooden cocktail stick, I used an interdental toothbrush to get the metal polish into all the awkward little corners.
After a good rubbing with cotton wool buds and a soft cotton cloth, the metal began to shine.
There are a few blemishes on the metal where the chrome has begun to lift, but considering the machine dates from about 1931, it is in very good condition.
To get all the rubbish out of the thread and the teeth which engage when the winder is in motion, I used a tiny bit of metal polish on an old toothbrush and rubbed it off with a cloth afterwards.
To clean the black japanned parts of the winder, I used a tiny drop of sewing machine oil on a dab of cotton wool.
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