Over coating a varnished floor

[Roger Feeley]

We have a very banged up wood floor in an 1860 farmhouse. This part of the house might be newer but it’s hard to tell. The floor appears to be some sort of pine. It has a lot of scratches and dings that go through the varnish and stain. We tested the finish with solvents and a paper towel with mineral spirits seemed to dissolve the varnish.

I want to be fairly minimal in refinishing the floor. I don’t want to sand the whole thing. What I want todo is:
1. Go over the floor with a liquid stain to darken the scratches. Wipe of excess. Waterborn ok?.
2. Lightly sand the whole floor with a handheld random orbital just to provide a bit of tooth and take care of any s remaining stain. Maybe 180 grit?
3. Varnish. My favorite varnish is from Vermont Natural Coatings and is an almost odor free. I will experiment on a small section to check bonding.

I put my specific questions in bold but I appreciate any suggestions.

[Mel Fulks]

If the pine is rift grain or vertical grain ,it’s really good stuff, and will hold up well . Some of the stuff looks like it never had any finish, and
some just keep it like that or just wax. 180 might be too fine ,but you are right to proceed carefully.

[John TenEyck]

We have a very banged up wood floor in an 1860 farmhouse. This part of the house might be newer but it’s hard to tell. The floor appears to be some sort of pine. It has a lot of scratches and dings that go through the varnish and stain. We tested the finish with solvents and a paper towel with mineral spirits seemed to dissolve the varnish.

I want to be fairly minimal in refinishing the floor. I don’t want to sand the whole thing. What I want todo is:
1. Go over the floor with a liquid stain to darken the scratches. Wipe of excess. Waterborn ok?.
2. Lightly sand the whole floor with a handheld random orbital just to provide a bit of tooth and take care of any s remaining stain. Maybe 180 grit?
3. Varnish. My favorite varnish is from Vermont Natural Coatings and is an almost odor free. I will experiment on a small section to check bonding.

I put my specific questions in bold but I appreciate any suggestions.

Varnish does not dissolve with mineral spirits, nor does shellac which is the film finish I would have expected on a floor that old. Are you sure it has a film finish on it and not just wax? That would be more likely on a floor that old. Mineral spirits does dissolve wax, and that's what I would expect was used on something built in the 1860's, unless it had been updated at some point along the way. But again, mineral spirits doesn't dissolve varnish, shellac, or any other finish I can think of besides wax.

If it is wax I'd say that's great news. If so, I'd just clean it really well with mineral spirits and a white or minimally abrasive pad. That will remove the dirt and fill in the scratches and dings, too. If you want it darker then apply a darker wax after it's clean. If you want to apply a true stain you will have to completely remove the wax, and that won't be easy. And if you want to top coat it with waterborne then you need to get the wax off 10X over in order for it to bond.

John

[Tom M King]

If it's Moisture Cure Urethane, which was the most used floor finish for several decades, nothing will stick to it.

An 1860 farmhouse probably didn't have anything put on the floors until well into the 20th Century. They would have just scrubbed them.

[Robert LaPlaca]

Well, to John’s point.

My neighbors house was built in the 1920’s (as was mine), her home has the same 1 1/2” wide quarter and rift sawn white oak floors as my house, where we differ is the neighbors house still has waxed finished floors to this date, by the way they are beautiful. She was concerned of a ‘dirty’ look of the floors, some helpful guy at Ace hardware told her to use Mineral Sprits on her floor, the Mineral sprits did a lovely job removing the wax from the floor.

[Roger Feeley]

Well I’ll be. I was taught to try mineral spirits first. If it cut the finish then you have old fashioned varnish. Then try denatured alcohol for shellac. Then try lacquer thinner for lacquer. If nothing cuts it you have polyurethane.

[John TenEyck]

Well I’ll be. I was taught to try mineral spirits first. If it cut the finish then you have old fashioned varnish. Then try denatured alcohol for shellac. Then try lacquer thinner for lacquer. If nothing cuts it you have polyurethane.

If by old fashioned varnish you mean oil based varnish of the non poly type, mineral spirits will not dissolve it once it's cured. If you mean something they called varnish from 150 years ago, then maybe that's true. I don't know what they used back then and might have called varnish. I do know that what we now call varnish consists of a resin and an oil that are cooked together to create a new compound called varnish. After it is cooked it is dissolved in mineral spirits or Naptha. When applied to your project the solvent evaporates and the varnish crosslinks through reaction with oxygen to cure. At that point it is no longer soluble in mineral spirits.

John

[Jason Roehl]

Sanding for floor refinishing usually stops at 100 or 120 grit. The standard of the industry is whether or not you can see sanding scratches from a standing position. Anyway, 120 grit would be appropriate for creating some mechanical tooth in a cured polyurethane that is to be topcoated. From the sounds of it, though, you may very well have a wax finish, as evidenced by the mineral spirits dissolving the finish. I also think over-staining is more likely to highlight the scratches than it is to hide them.

Addy protocol: refinished wood floors professionally for 10+ years

[Maurice Mcmurry]

Your old floor might have been oiled. Watco used to make "floor finish". It was a heavy duty version of their Danish Oil. It was popular for antique homes. I used it on Pine flooring at the recommendation of a restorer of historic buildings in Boston in the 1980s. Pine floors are a difficult finishing dilemma.

[John TenEyck]

Your old floor might have been oiled. Watco used to make "floor finish". It was a heavy duty version of their Danish Oil. It was popular for antique homes. I used it on Pine flooring at the recommendation of a restorer of historic buildings in Boston in the 1980s. Pine floors are a difficult finishing dilemma.

That brings back the memory of my father telling me that he had to "oil the wood floors" every week at the restaurant he worked at as a teenager. That would have been back in the 1930's. I don't know what kind of oil it was but suspect it must have been something really light and mostly solvent in order to be dry by the next morning. Whatever protection it offered must have been minimal since he had to do it every week.

John

[Roger Feeley]

Thanks to all that replied. I’m thinking that this is going to be more of a trial and error as I test different approaches. Fortunately, there are a few spots where no one will ever look.

[Roger Feeley]

Well, we finally got enough access to the floor that we could look under a large area rug. There are places where the old finish has peeled and cracked off. Underneath there is bare unstained wood. I assume that the old varnish had the pigment in it and there was not a good bond between that finish and the wood.

I’m wondering if I should play it safe and use some sort of penetrating oil instead of a varnish.

[Maurice Mcmurry]

I wonder what the chap from Norman Rockwell's "The Painter" was using? he sure was a patient fellow.

IMG_0651.jpg Its Monarch 82 floor varnish. I wish I had some.