I wanna be a hooker!

[J Anderson]

Given that the lane surface smoothes out the finish on a reactive resin ball, I would assume the same is true for polyester. If that's the case, it's not worth sanding.

I think its the the lane surface changes the finish of any ball. A ball that is finished with a very coarse grit will get smoother. A ball with a fine grit finish like 4000 will get rougher. Either way your advice to polish the spare ball is right on.

[Tampabaybob]

The spareball I use is a pyramid, If I try, I can hook the ball quite hard on dry lanes, and even a decent amount on oily lanes. The ball will also grab the dry parts of the lane at times and change the ball direction slightly resembling a hook. I wonder if there is a straiter spareball out there, or do I just need to polish it up, or maybe even sand it. I havn't heard anyone talk about sanding their spareball yet, sounds like a bad idea.

Polish your spare ball once every two league sessions and you "should never" miss another ten pin or six-ten.