Adding some luster back to hardwood floors

[SarahFair]

The previous owners left me some lovely deep scratches on the floor while moving her stuff out.
Some of them measure 6 to 7 feet or more.

There's also your everyday worn areas.
I've hid some with Howards, some won't take it. I've thought about sanding those areas and adding a little stain..

To clean the floors I texted some areas with Murphys, but I didn't notice a difference.
Im wanting something to add back their luster.

What would yall suggest to help disguise the scratches and what should I use for an overall cleaning/finish?

[1918ColonialRevival]

All Murphy's really does is clean off the top layer of dirt. If there's a lot of caked on crud, I'd use some naphtha or mineral spirits and #0000 steel wool to get that off, then follow with a wash of Murphy's to remove the residue.

As for the scratches, there's really nothing to get them totally out short of sanding the entire floor, which I don't necessarily recommend. I would find a stain color that is close to the color of the floor and spot stain the scratches. Let the stain sit on for only a half minute or so and then wipe it off with a clean rag and let it dry.

Much of the luster of old wood floors is brought out using paste wax. A lot of rubbing, but they come out looking pretty good.

[cat2014]

What about dog nail scratches? Same procedure? Has anyone used Bona for hardwood floors?

[phil]

you could try a bit of dainish oil. test a spot in a closet or somewhere. Just rub it on and wait then rub every bit you can off with dry cloths. the oil won't absorb where there is finish since that's non porous. only where the scratches are. it'll hide them as it's the whitish mark that really shows more than the missing finish.
If you want to refinish you might need to know if it was shellac or if it was a water based product. If it's shellac you can put another coat on and it'll meld into what's there. If it's poly you can scuff sand and recoat with more. If it's water based I'm not sure about re-coating it. ask the others.

With poly, you can run into little issues where you sand through some areas because the perimeter of the feathered area near where you sand through gets micro thin. The poly solvents then may creep under and lift a little leaving a bit of a roughened ridge where this effect happens. You can knock it down with sandpaper when dry and recoat. If the poly is still gummy and balls on the sandpaper you can try fine wet or dry sandpaper wet with solvent but avoid breaking through or you'll see the problem I described above.

I'd try the danish oil trick and see how you like it. it's easy. It won't fix the scratches but it should make them less apparent. Don't use colored oil or it will enhance the scratches as they will catch the pigment. You could sub blopentine for danish oil. It might take a few applications to make the scratched areas shine like the rest but the danish oil can be used as a finish in itself.

if you do this check after an hour. sometimes the oil goes into cracks and then bleeds back onto the surface and if it's still wet just do another rub down with dry cloths. If it's sticky or anything add some turpentine. clean it and let it dry first so you don't' imbed any dirt.

before you do that, try an experiment on something else or some area to make sure you like the effect but that's what I'd try to do. it won't totally hide it but it'll take your eye off it and you can worry about something else

[eclecticcottage]

I'd try linseed or tung oil-if I'm recalling right, linseed won't darken quite as much as tung.

All of my floors are oiled rather than polyed or finished in any way. If there's a new scratch, some tung oil touches it right up.

[phil]

I'd do a coat of whatever you have on-hand that is a clear oil and not like engine oil or cooking oil it just has to be a wood finishing oil. , sure use linseed and turps or tung if you have that on hand you don't' need to go buy more if you have one of them. just don't use a colored oil for the first pass as it may darken the scratches because that's where the pigments will collect.
If you want it darker you could carefully use darkened oils but you'll likely find any oil clear wood finishing oil will make it a whole lot better. You need so little , just enough to dampen a tiny rag for this since it already has some sort of non porous finish it won't absorb where the finish is. Its just a trick to hide the scratches without resorting to refinishing the floor. If it were an oil finish I'd do the whole floor but from the pics it looks like its got some sort of clear coating. Knowing what dissolves the clear finish and what does not might give clues as to what is on there and you;d want to know that if you want to do more and actually refinish it.

[nhguy]

Since we're on the subject of flooring. I have yellow birch flooring with a clear finish, I believe to be varnish since it, doesn't discolor when it gets wet, like shellac. There are a few worn spots, my wife is talking getting them sanded, ugh. Will using tung or or my favorite 50% linseed and 50% mineral spirits work on the thin spots? I hand stripped 3000 sq feet of pine(hemlock actually) and used the above mix. I've never tried it on hardwood flooring before. Thanks

[phil]

my suggestion was to use it to hide some scratches. You can test before you do the whole floor. it sounds like you have some bare spots. I think it would help make it look better and may be a way to make it look better enough that you can leave the floor as is. You can only sand too many times and since there is no wood loss you can still sand it some other time if you have enough wood to work with.
what is varnish exactly? a quick definition online reveals "resin dissolved in a liquid for applying on wood, metal, or other materials to form a hard, clear, shiny surface when dry." so that really means any clear coating and not necessarily a specific product. If you are looking to recoat over the existing finish then you should try to determine what it actually is. It might mean polyurathane or it might be a mixture of some different products.
I dont' think it matters what the finish. test first but in my opinion you can use the technique of putting some linseed and turpentine on with a cloth and wait a few minutes then wipe all you can off, You can repeat the next day if you want to. the idea is that it will only soak in where the floor is scratched and wipe off anywhere else so the wiping up is important.

If it were fresh sanded work it would soak up most of the first application and on each subsequent application it will take less oil into the voids and since some is already near its maximum absorption. the rule of thumb is one coat a day for a week , then every week for a month , then once a year thereafter and yes you can use that as the only floor finish with great results. poly , or shellac or other clear coatings like lacquer don't really soak into the wood they lie on top and form a clear protective shell over the wood. You can do both , oil , then your clear finish and that will harden the floor ( the wood) a bit before you put the shell over it. many prefer to leave just oil and do applications periodically to restore the finish. Its not quite as hard wearing in some ways as poly which is why poly is more common but it does have the advantage of being easier to recoat. It looks nice because it doesn't have that shiny shell over the wood. Applied properly it's a beautiful wood finish and yes it is suitable for floors all on it's own.

"Polyurethane was discovered in 1936 and became commercially available around 1940 "
http://thecraftsmanblog.com/a-history-of-wood-floors/
...So it's not a new finish. but some of us have older houses and many had shellac on the floors so the option is yours.

water based polyurethane is a different animal. it wets the wood like water wet. this raises the grain on the first application and the coats go on thin like water. I haven't; much experience with the water based stuff or in recoating it so it might show some different tendencies than the traditional oil based polyurethanes. if your floor is oil based polyurethane you could also just give it a good cleaning and sand it lightly to give the new "shell" something to stick to, you can re-coat right over the old poly if you want to. normally poly is put on in more than one coat , maybe 3 coats. if they are done when it is dry enough to walk on but not fully cured then subsequent layers will cross link so between these layers you have a chemical bond. If you coat an old poly floor with more poly it will only bond through mechanical means it won't melt into the previous coating. That doesn't mean it will flake off or anything like that. most paints and coatings dont' combine with whats underneath through cross linking. If you paint something it's a mechanical bond usually.

another example is the comparison between lacquer and enamal paint. If you put lacquer paint over old laquer paint it will combine. If you put oil based paint , like a common spray bomb over previous coats of oil based paint, the new coat will lay right over the older layer. It isn't really melting in to the old finish like lacquer or shellac might. It will stick fine as long as the surface is clean but it isn't' melting in to the old finish.

If you don't' know if your finish is oil or water based polyurethane I am unsure how you can detect the difference on the finished wood but maybe someone else knows this. The water based stuff is more common these days and many industrial practices are leading towards the water based stuff because of VOC's. Some commercial floor finishers may tend to avoid the oil based products and some may refuse to use oil because their health is part of the equation.
another way to make some of the finishing products harden is by UV curing and there are products out there that are designed to be hardened by UV lights.

one important difference is with the way these products combine when re coating. if it is just oil it will accept more oil. if it's got shellac or poly or lacquer it will seal the porosity and it won't accept oil. If it's shellac and you put more shellac over top, the alcohol in the shellac will meld into the old shellac underneath so you are combining the two finishes. lacquer is the same , if you put lacquer over old lacquer, the lacquer thinners in it will melt into the old lacquer and combine. You can do this but in each case you have different things happening. with poly, it cross links as it hardens. once hard poly can't be dissolved easily by it's solvent. in fact if you do a poly finish and need to sand it within a day or two you'll find it tends to ball on the sandpaper because it isn't really hard yet. it takes time to cure so if you were between coats and wanted to finish you can sand the poly with its own solvent , wet or dry paper wet with solvent wont' dissolve the fairly new coat of poly and will help to stop the stuff from balling up on your sandpaper. if you do this try not to break through to the wood as you can sometimes see a slight effect where it is feathered to almost nothing , then the solvents can get under the micro thin where it is "feathered" to where it sanded through. the problem can be hidden by more coats if that happens.

you mentioned mineral spirits. this term seems like it may be different from one person to the next. Both can be used as a thinner for oil based paints but some may think it's the same thing and some may refer to mineral spirits as any paint thinner. If you go to buy it look for turpentine. Im not saying it wouldn't work but I think "real" turpentine is more expensive and works better than a lot of the cheaper solvents that you might use for cleaning brushes and thinning paint. turpentine is also good for cleaning brushes so if you have good paint brushes that you care about and you use them for oil paints then I'd use turpentine to clean them in, for a cheap brush it might be too expensive, but a good quality paint brush is worth taking care of.

turpentine wont' dissolve shellac but if you used a solvent that had alcohol in it the results might be that it might start to dissolve your finish and that might not be good so do tests to make sure it isn't causing issues and you like the effect. above I have compared some different products but there are a lot of products on the market. You might find that not all turpentine or all lacquers or all types of polyurethane are the same and if you were a chemist who could analyze more you might note some chemical differences between brands. I think "real" turpentine is a derivative of the liquid you find between the bark and the trunk of a tree and may come from different trees and some may contain things like alcohols. . I think a lot of the things you might find to wash brushes in are likely petroleum based products.

note that if you pile up used oily rags they can spontaneously combust. The pile can start to actually bust into flames with no heat source. the heat is produced in much the same way that you may see in your compost pile. If people aren't aware of it they can sometimes start fires when they just weren't' aware of the danger. If you go turn over a ripe pile of compost you may see sparks. Fires can start naturally this way even out in the forest under the right conditions.

[nhguy]

Wow, that is the most amazing answer I've had on an old house board. Phil, thanks so very much for your explanation. I'll take some time over the next few days to experiment and find out what the finish is on the floor. When I say varnish, I mean the old fashioned, oil based type that came in a gel form or brushed on in either a satin or gloss finish. I try never to use polyurethane either or or water based. Again thanks.