I am refinishing floors in a house I just bought. I think the floors are pine, not really sure of the species. I do know that they are not oak. The floor is perfectly flat, its in great shape as far as the quality of the wood. I want to apply a dark stain when I am done sanding. But I do have a couple of questions for you guys.

1 Do I need to sand inbetween coats of finish with a small handheld sander?

2 How many coats of poly should I apply?

3 Whats the time frame inbetween coats of poly?

And if there is anything else please feel free to let me know. I have refinished a floor one other time with a drum sander. Not a bad job but the finish had bubbles. This time I am going to try one of those 4 disc sanders at Home Depot.

all the anwser to your questions should be on the can of finish you will be using. you can learn a lot from reading those labels. as far as bubbles in the finish it doesn't have to do anything with the drum sander.could have been from the stain not being dry enough before you apply the poly.

A dark stain on pine will blotch, that is it will come out very uneven. Use a pre stain conditioner before staining. Follow the directions on the can carefully and make a test run somewhere inconspicuous like a closet.

Staining is very difficult on floors for a DIYer. It can very easily blotch or highlight the sanding scratches. If you use a random orbit sander (4 disc sander) you will more than likely have little pigtail swirls all over the floors that the stain will highlight. Make sure you go through all the grits and finish with a fine grit. Its the courser grits that leave the visable pigtails and you must get them out with the finer grits as you go. Also as Jan said use a preconditioner. I have found the Miniwax pre stain conditioners to work very well. I would not recommend staining a floor unless a very experienced person is doing it. Try to start with the finest grit you can to remove the old finish.