[Mondial]

Mike, if you decide to wash the tuning cap in water you might want to remove the mica insulators from the trimmers, or at least open them up fully. Water trapped beneath the mica can take a long time to dry and cause corrosion if they are screwed down tight.

Your cap looks pretty clean, and if it were mine I would just brush off the dust and blow it out carefully with compressed air, being careful not to hit the trimmer micas.