Russ,

I am pretty much the same way.  I do ball maintenance after every 6 to 9 games.  Anytime I use something that is to clean the oil and dirt off the surface of the ball, I go ahead and repolish it.  If I was you, I would sand the ball back down to a 400 or 600 grit (starting at 400 and working up to 600) to get the surface fresh.  Then take some Storm 1 or Ultimate Quick Cut and do a once over followed by Storm 2 or Storm 3.  If they do not have Storm polishes, go with Ebonite's Factory Finish Polish.  After I polish a ball for about 3 months, I do the same process over again, due to polish build up.  Every 3 months, sand the ball down and then repolish.  I have done this to several balls that I still currently use.  The balls react as good now as they did back then without a loss in hitting ability.  The polishes durability also depend on how you roll the ball.  High rev players such as myself, will develop a track in the ball usually after 3 to 6 games.  A stroker can go probably closer to 18 to 21 games before ball maintenance is needed.  Another factor is the lane surface (wood or synthetic).  Wood might eat away the ball surface faster because it is a higher friction surface.  Either way, for me, I clean and polish after every 6, but no more than 9 games.  I hope this answers your question.
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