Solid Hardwood, Engineered and Laminate Flooring - Grits for sanding and other questions

Greetings all, we're in the middle of our floor refinishing project (pine floors), we just got done stripping all the old finish off using 20 grit on a drum sander. From reading the online project How To on this site, it suggests going to 80 and then 100 grit. Is this also what most people would reccomend? Or is it needed to go to 36/40 to 60 to 80? Our stain manufacturer says not to go higher than 100 grit before staning (we will be using wood conditioner). Polyurathane says no staining is neccessary between staining and the polyurathane. Do we need to put the polyurathane down the same day we finish staining, or can it wait a day? How about waiting a day between sanding and conditioning/staining? (I know from the label that the stain must be applied within two hours of conditioning.)

Thanks all!!!

Never skip more then 20.

20 40 60 80. Or you will be there all day trying to get the scratches out from the coarse paper.

20 grit is very aggressive for pine. 40 60 80, is usually recommended for soft pine.

You can finishing instructions at the National Oak Flooring Manufacturers' Association website: www.nofma.org