Newb question,

I'm attempting a home hardwood floor refinish, and I've got the first coat of Poly (Oil-Based) down. I've buffed it - but here is where I've messed up at the end of a tired day.

I tacked the floors with Mineral Spirits - and in hind sight, probably far too much. I basically mopped it - maybe a cup of MS over 600 sqf., - instead of using a damp cloth. I've read that I may have issues with streaking, but I was more worried about adhesion with the next layer.

Will too much mineral spirits "dissolve" the buffing in the oil-based poly? Do I have to buff/screen again? It'll be a week before the next coat of Poly.

Thanks,

PF.

You will not dissolve the poly-urethane by tacking or washing the floor with mineral spirits once it has dried enough to create powder when buffing.
If you used a hundred grit screen and a white driver pad to buff the floor between coats of finish after the seal coat has dried, you may use only a rough pad like a black or red one to polish off any powder and scuff the floor before your next coat of finish. You can also use the used 100 grit screen on the side that has been used before with your driver pad so you make less powder and take off less finish.
Tacking requires a towel sightly dampened with solvent. It can be water, too.
I spritz a towel under the kitchen tap to just dampen it, then "cook" it in the microwave to have the steam penetrate the whole towel, so I use less water.

Thanks - I was worried I'd undone my initial buffing by "dissolving" my scuffing.

After the first coat I pole screened with 120 grit screen (and then mopped the floor). Should I rescreen with a finer grit after my excessive "cleaning" before the next coat of poly?

I would save the used screen and buff with it before you apply another coat. 120 grit is fine. Sometimes a 100 grit screen will leave swirls in a finish if the coat is too thin.