"Amateur" wrote in message
news:5fe082ba8f4ccea2a90b9298e0e42954@homerepairli ve.com...
What kind of preparation needs to be done before applying an oil-based
stain to a pine floor, other than sanding down to bare wood and using wood
filler where needed? How long would the time interval need to be between
the stain application and the first coat of polyurethane? Thanks.

Pine stains best with a sealer or spit coat of shellac on it. That wood
filler is probably going to stand out too once stained. you may want to try
it on a pine board first to be sure it won't look like crap.

Once stained, wait about 24 hours for the first coat of oil based poly.