With the basic sanding you lay down the surface before you apply polish. And, yes, there is a difference between the grits before you use non-grit polish like Brunswick's High Gloss Polish. The higher the grit, the smoother the surface will be. Sometimes, when you use 400 or 600 grit as a base, you can still make out the sanding marks "under" the polish and use them to influence ball reaction.
A ball will be different, depending on the basic grit. Therefore, 1.500 grit polished (on Storm balls) is something different than 400 grit polished (on Brunswick balls) and might be the best option for the particular coverstock material and company polish. Changes will make differences.
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DizzyFugu - Reporting from Germany
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"All that we see or seem, is but a dream within a dream..." - Edgar Allen Poe

When you change the surface, to what ever grit, that's the grit of it. Adding a polish that has NO grit compound in to, will only 'cover or fill' the sanding lines. The grit will not go up, that much. UNLESS...you apply so much pressure and 'burn' the polish into the cover, then it's a pretty good change. To what ? good guess, since pressure and ampunt of time on each side varies from person to person.

I've seen a guy that can really bogg down his single speed spinner with pressure. I apply a lot of pressure when starting a resurface, but as the grits increase, the pressure is lighter. Polish is simular, so to say that a polish will bring it up to XXXX grit, again unless it has a grit finish in the compound, then it's tough to say what you will finish.

What I'm saying is, I know MY pressure, I don't know yours.

JMO
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AZ Guy aka: R & L Bowlers Pro
rlbowlerspro@cox.net
www.rlbowlerspro.com

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