I'd clean the ball after each use, and just think about surface work once the track area starts tracking out - it becomes dull, and the ball will have less length. Sometimes, this can be a wanted effect, but that's when you should IMHO consider a surface refreshment.
In any way, make sure that the whole surface area receives an even treatment - that is, re-sanding it from 4 or 6 sides to the appropriate grit, and evenly apply polish or compound on top of that.- this ensures that the ball remains round and complys to regulations.
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DizzyFugu - Reporting from Germany
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