How challenging is it to sand a stained oak floor?

Question

I am about to do a little touching up of a stained oak floor.

I am concerned that sanding the floor with a machine would be infeasible because it means that the stain would be gone from some parts more than others, and then it will be necessary to do a heavy sanding, staining from scratch, and apply multiple polyurethane coats.

In your experience, is it possible to do local touching up of such a floor, perhaps by a tedious but more gentle hand sanding? Or is it just a job that has to be done for the entire area?

Answer 1

It depends. If it's fairly small, doing it by hand can save time and money and effort. But how small? On top of that it's location is also important. Is it the size of a small throw rug and in the middle of a high traffic area? then it might be a lot harder to get it to match and not stand out like a sore thumb, especially if you haven't done something like that before. Is it under a window where there is some water damage and can be hidden by a piece of furniture? then it might be worth the trouble of hand sanding and refinishing.

My dad has completely done several wood floors. Renting a big sander for the floor and doing the whole floor at once (according to my dad) really doesn't take that long and leaves you with the best finish. Last one was my Sister and brother-in-laws dining room floor. It's about 15' x 13' and they had it all sanded in less than a day. So with a little help and planning, the entire floor could be sanded down and refinished in a weekend. (depending on size of floor)

Answer 2

I would opine that hand-sanding any significant area of floor is just not viable. It's not that it's actually impossible, but the amount of work — both time and effort — needed to do it is just so great that it's infeasible for the average person. It's backbreaking work, both literally and figuratively.

You can however get down to bare wood by handwork in a reasonable timeframe, by using one of a couple of types of scraper. For a small enough area, anything roughly the size of a table, you could comfortably use a card scraper (see bottom of previous Answer). For much more than that you're probably better advised to use a scraper plane or a gullwing scraper, e.g. Stanley no. 80. I should mention that neither of these last two options is inexpensive; card scrapers on the other hand are cheap.

Or is it just a job that has to be done for the entire area?

Broadly speaking, yes. Varnishes are considered un-repairable finishes, while this isn't absolutely true it does mean that touch-ups and additions are hard to impossible to do without them being obvious and in addition to visibility fresh varnish does not bond well to fully-cured varnishes so there is a high potential for peeling at the edges.

Answer 3

The correct answer or at least the canon answer @bowlturner has already mentioned. Doing the whole room is the best way to do things. That said...its more expensive and more time-consuming.

If your problem is in the middle of a floor, in a high traffic area, spread out over a decent sized area (2 sq feet ore more really) or otherwise blatantly obvious...yeah you are going to have to sand everything (it would be best if you could post a picture of the area you need to fix).

Now...all that said I have touched up spots on floors before...and while they personally drive me insane because I see every minute flaw, most don't notice.

For a relatively small flaw/area here is what I have done (and to all the perfectionists, no...I am not proud of this :) )

Tape around the area as tightly as you can, meaning don't make it a square. Give about 1/2 inch between the tape and the flaw(s) all the way around. Make sure you use quality tape that will not pull up.

Sand...yeah I said it...sand. Now. How much you sand depends on the depth of the flaw. If it is just a flaw in the finish...ignore everything I said, get some floor wax and buff the crap out of it. Problem solved.

If it is deeper, meaning into the wood, sand as needed to smooth things out, apply a stain absorbing filler if necessary. Sand the entire taped area at least enough to roughen up the finish.

Clean really really really well.

Apply finish. I actually use an aerosol spray finish most of the time, they usually come in satin, semi-gloss and gloss. Spray the finish and let it dry completely, use thin coats of finish.

Sand.

Apply finish.

Sand

Apply finish.

Pull the tape painter style (back on itself rather than up).

Sand with a smooth grit paper or sometimes you can get away with a 0000 steel wool...be gentle either way.

Once that is done buff/polish the floor and it should blend in pretty decently.

This method is all about touch, go light, if you're heavy handed it'll just be a pain