This calculator didn’t need much repair.

1. It was cleaned inside as well as outside. For the inside a solution of  gasoline with ca. 5% thin oil was used.
2. Parts that seem to be heavily loaded were lubricated. Light oil for shafts etc. Teflon grease for gears.
3. The commutator of the motor was cleaned and slightly polished. The brushes were cleaned as well.
4. The drive belt was quite stiff.  Leather grease seems to help well
5. A capacitor directly connect to the mains connector pins exploded.  It’s only function is some interference reduction.
   That may have been useful at  the time when mid-wave radio’s were in full use.  I left it out for now.

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