Scraper scrapes off finish in layers

Q: Two weeks ago I had my hardwood floor refinished. We moved the furniture too soon and caused damage. The contractor who finished the floor is coming back to refinish; however, now we can take a scraper and all the finish scrapes off in layers. Is this normal? Has the floor not cured? Will it eventually harden? This is one room and there were four others done at the same time.

A: Difficult to say if he has failed to gain adhesion between coats or if he applied the finish in too thick a film. Many finishes have a spread rate of 500 feet per gallon.

White scratches on teak floor

Q: We had a water leak and had to replace a small section of teak flooring. The insurance contractor said that we needed to sand the entire floor down so it would all match. They put 3 coats of oil based polyurethane on the floor: satin, then a semi and then a satin since I was concerned about scratching. Our floors were beautiful and were fine prior to this work. Now there are white scratches everywhere from shoes and our dogs.. within days. Do you think this could be from bad bonding between the coats, not enough buffing between coats? It is getting worse and worse. We had normal wear and tear with the way our old floor was but never white scratches, which really are not scratches in the floor but the top coats of oil. I am trying to figure it out between the contractors and the people who did the work. Thank you.

A: It sounds like the finish is rapidly wearing off because of a poor bond. I suspect the cause is the oil in the wood reacting with the solvents in the finish. I would instead use a water base finish such as Poloplaz Prism or similar coatings from other manufacturers who provide a barrier coat with their sealers.

Is this shellac on my hard wood floor?

Q: I was hoping you could give me some advice. I rent an apartment which has nice hard wood floors. I have been here for 2 years now and have noticed the shellac (I think it is) is peeling off in spots. It is becoming worse and more noticeable. How can I fix this and prevent more shellac coming off? I want to take care of it before it gets worse.

A: If your finish is shellac it will dissolve if alcohol is applied. More than likely somebody has applied a coat of finish (polyurethane) over an existing coat without proper preparation to gain adhesion. The real solution is to remove at least that top coat of finish by screening with a polisher and abrasive screen, or more realistically to have the floor completely re-sanded and finished.

Mystery peeling around perimeter after 18 years

Q: We’ve had a decorative wood floor in our dining room for about 18 years. installed by a local guy, with pickled ash finish and a dark cherry perimeter. The wood was prefinished when we installed it. Today we picked up a cardboard box off the floor, and the finish seems to be peeling off the dark cherry. It doesn’t seem to be caused by the box (it was there for a day and was heavy, but no residue on it). The only thing I can reason is that we have skylights above the dining room and they are unobstructed to the sun, perhaps ageing the finish. What happened, and how do we fix it?

A: This is quite a mystery, isn’t it? The sun shining through your sky light didn’t peel the finish in 18 years and I know of no reason it would suddenly do that. The card board box wouldn’t cause this either. At least not on it’s own. Unless something was spilled inside the box or at some point the bottom of the box was set onto any chemical which would attack polyurethane coatings. Things such as strippers, acetone, perhaps nail polish remover? If this is restricted to one or two boards I would wipe them down with a wet cloth to neutralize anything which may be on the board. I would gently but thoroughly rub the entire board down with fine sandpaper or other appropriate abrasive. This scratches the existing coating allowing adhesion of a new finish coat. Apply a thin coat of polyurethane with the same level of shine. If a second coat is needed, repeat the process.

Lap marks in amberized sealer

Q: I am in the middle of refinishing a 75 year old white oak parquet floor. The customer wanted the older yellowed look and opted for amberized sealer. While applying I noticed I left a large 10 inch path a few feet long where it wasn’t smoothed enough and now shows a line. I applied a second coat of amberized sealer and am waiting to see if it disappears by tomorrow morning. If not, how do I get these huge lap marks out of a water base amberized sealer?

A: I’ve never used amberized water born sealer. I would call the manufacturer of the finish. However, especially being white oak, isn’t it possible the streak is a tannin reaction? I suspect you will have to scrape the mark out and try that spot again.

New wood is shiner than the old wood after finishing

Q: I have a original 1957 wood floor that we sanded. We had to replace some parts due to damage. When we put semi gloss poly on it the new wood is shiner than the old wood. How can we make it come out all the same?

A: It should all be the same if you stirred the finish well. It could be the old wood is now well dried out and more porous than the new. You have more of a build on the new wood than the old. Apply another coat. Satin also looks very nice and would be closer in look to a floor from 1957 where wax was common. In any case make sure satin or semi gloss are stirred well, not shaken. This will evenly distribute the paste in the mix which determines the level of shine.

Oil based polyurethane finish looks “dimpled”

Q: We recently had our red oak floors refinished, using Min-wax Red Oak color, and we chose oil based polyurethane. We contacted the refinishing company after the third coat of polyurethane was applied because we thought the semi gloss sheen looked somewhat cloudy where the light hits it, but clear when standing directly over it. Is this normal for semi gloss finish?

Also, I’m not sure what the correct word is, but dimpled comes to mind. The poly appears to be dimpled, or lightly bumpy, meaning not totally smooth. Is this normal? It’s not referring to sand or granule stuck in the finish, but a subtle dimpling across the entire floor.

The room was kept at 60 degrees for drying, and one day in between each coat. The flooring company explained this “dimpling” was normal, as the floors take 6 months to cure and therefore appear smooth, I am wondering if this sounds accurate.

A: The finish may have set up too quickly, not allowing it to flow out level.

I don’t know what finish was used but all except gloss have a paste (silica) added to reduce shine. I don’t know if something was up with that – not mixed well enough or an issue with the paste settling to the bottom of the film.

I had that happen once years ago. But since using Poloplaz Primero I’ve never had any issues. It is an excellent coating.

Blending finish overlap “ridge”

Q: I just redid my hardwood floors and they turned out great except for one area. There is an overlap ridge and I would like to know how to get rid of that ridge so it blends better. It has been sitting for almost 24 hours.

A: Are you saying this is with the finish you applied? If so, it sounds like probably a water borne urethane which sets up very quickly generally. You could try lightly abrading (very fine sandpaper or an abrasive pad; don’t use steel wool with water borne coatings) the entire boards affected, taping off the boards involved. Apply another thin coat and immediately remove the tape. If that doesn’t work you will have to re-coat everything. Remember, thin coats are always better than thick ones. All finishes have a recommended ‘spread rate’ such as 500 sq. feet per gallon.

Milky marks appearing in finish of exotic wood floor

Q: We have Brazilian cherry floors with Swedish finish, installed in 2004. There are milky marks appearing in the finish. They now look like tread marks from athletic shoes. We don’t have any shoes that match the pattern. Any clues to what is happening?

A: I don’t have a great deal of experience with exotic woods such as Jatoba. To tell you the truth, I try to stay away from them.

I know it can change colour rapidly and in fact have seen it.

I’ve also heard that white marks can appear in some batches of Jatoba as an interaction with extractives in the wood and solvents in floor finish but I don’t know why it would take this long to appear if that were the issue.

Finish peeling due to too many coats of stain

Q: We really need some advice. We just moved into our new construction home about a month ago. The moving company used packing tape to tape down blankets to protect our newly finished hardwood floors. When they pulled off the tape, big sheets of the polyurethane came off. Thinking it was just an issue with the adhesive on the tape being too strong, the floor guy came back and “redid” those areas. However, we have noticed that wherever our dog (about 50lb and nails always clipped) has made any scratches (even slight) in the floor, the polyurethane is flaking off. You can literally peel it off with a fingernail. We have had dogs before on other hardwood floors, and while they may scratch it, the clear coat has never flaked off like this. We have wide plank, new heart pine. It was stained with 3 coats of Dura Seal Dark Walnut stain. They used 3 coats of Gerner Clear Satin polyurethane. It was sanded in between coats. Any guidance you can give us as to why this is happening would be greatly appreciated.

A: This issue is definitely not the fault of the tape. I’ve done tests on boards I’ve stained and finished with a variety of tapes including Gorilla tape, pressed onto the boards and left 5 days. I removed the tape after that with no issues. I have to ask why your floor guy applied 3 coats of Dura Seal stain. I’m afraid to apply two coats in case the first coat of finish isn’t able to reach the wood to gain a bond with that. 3 coats? Wow, I’ve never heard of that and as you can see, it isn’t a wise thing to do. If they wanted a darker colour they perhaps should have considered water popping first which opens the wood grain for a darker, more consistent colour. The only way to fix this I’m afraid is to start over.

Follow-up Q: We did 3 coats to achieve a darker color. 2 coats wasn’t enough to achieve the color we wanted. I’ve never heard of water popping. Can you explain that please?

A: It is easy. After all wood has been completely sanded and prepared with dust vacuumed up, wet (not soak) the surface of the floor with warm water. It doesn’t have to be warm. Don’t miss any spots. Allow this to completely dry and start staining. Do not drag or scuff your shoes on this lest it close up the grain in that spot and you end up with a light spot. That is all there is to it. If that doesn’t give you a dark enough colour then go with something darker. Final sanding should be finished with 100 grit and not finer than that. If the wood is too smooth you won’t get any stain penetration and the colour will look awful.

Follow-up Q: So, in your opinion, too many coats of stain were used causing the polyurethane to not adhere properly? And our only option is to start over completely?

A: If each coat was lightly sanded between each coat then that would appear to be the reason. It sounds like it is peeling, not between coats but right off the stain. There is no other way to fix it I’m afraid.

Installers added a coat of finish to prefinished floor

Q: I recently had new hardwood floors installed. They are pre finished flint maple pergo. The guys who installed recommended putting a poly coat down to protect them a bit better since we have a dog. We did the first coat, and it’s peeling in spots. We screened the floors. Will this help for the second coat?

A: We are talking about a real wood veneer and not laminate, correct? I would never suggest to a home owner to try to coat an engineered floor or anything factory finished. For one thing, they use finishes which are formulated to be abrasion resistant which makes it difficult in the extreme to impossible to adequately abrade the finish so as to gain adhesion. Their are chemical preparations designed to help with this, though I’ve never used them. The fact you have peeling spots proves my point. If the surface wood veneer is thick enough you are likely going to have to have these floors sanded to clean wood to fix this. I would suggest you contact Pergo and ask for their advice. I’m sorry this has happened to you. Always research first

Follow-up: Thank you for your quick response, I appreciate it. It is real hard wood yes, not laminate. I will call them today. My fingers are crossed that this is not the case. I followed what are flooring guy told us to do since he is the professional, but you’re right I should have researched.

A: I hope it works out for you. Beside the inherent risks in undertaking what you have started, even for a professional there is another issue that calls into question the advice you got. If a floor has an inferior finish to what you have then it might make sense to apply a better quality coating over an inferior one. This would be an upgrade. It is highly unlikely you would have access to a finish of this nature, so what has actually happened is you have given your new floors a down grade. Sad but true. In a certain sense, it’s like buying a beautiful new couch and leaving the shipping plastic on it to protect the fabric.

Follow-up: As suspected abrasion seems to be the culprit. I called the manufacturer and was told the exact finish they use. An aluminium oxide poly with water base. Oil was used on the floor. Trying to decide best move.

A: You can apply oil based over the water based. The problem is the aluminum oxide polyurethane is abrasion resistant. You said there is peeling in spots. How to know if the rest will fail also? Basic Coatings has a chemical prep you can use. Or you can get a roll of 120 grit and hand sand the finish thoroughly. I prefer oil based finishes. They are easier to work with and I like the look. However, typically water based can be applied consecutively without buffing between coats if applied within a specified number of hours which can be a plus.

Follow-up Q: If you were in my shoes what would you next step be? How would you handle this?

A: I would start sanding the finish with a fine abrasive. Every square inch. It will give you a good idea if you have a bond with the finish which hasn’t peeled yet. Once I’ve done this thoroughly, vacuumed up the fine dust and tack rag it clean, apply a thin coat of the finish of choice. You may have to do this twice. The main objective right now is to get a good bond between the original coatings and the finish you are applying.

Poly repelled from seams of sanded wood floor

Q: I just sanded some old floors that I installed about 20 years ago. I sanded them with 40 grit, 60 grit, 80 grit, then buffed it with 100 grit screen. Then I put golden oak stain from Minwax. After the second coat of Lenmar oil poly, I went to put third coat on and I noticed all through the house at the seams and the butt joints the poly looks dry and the middle of the board is shiny. It looks like I missed polying the seams. What could have caused this? I have picture if you would like me to text them to you.

A: Sounds like a contaminant. Were these floors waxed by chance? Because it can get into gaps between the boards and the solvent in the polyurethane causes it to bleed out and repel the polyurethane.

Q: We moved into a 50 year old house. Before moving our furniture in, I sanded the floors, applied several coats of Minwax oil-based stain, and applied three coats of Minwax polyurethane, also oil-based. Five months later, the polyurethane appears to be separating from the wood at the cracks between the planks in high-traffic areas and in some places the separation creeps toward the middle of the planks. The floor boards do move somewhat, but aren’t particularly unstable.

Is it common for the movement of boards when being walk on to cause this separation of the finish? Should the finish bond strongly enough to the wood to tolerate this? Maybe some contaminate is to blame? Is there any way to fix the problem spots so the bare wood isn’t exposed?

A: If the finish is peeling in the center of the board, you probably didn’t buff/scratch the previous coating enough to gain a good bond.

To fix it you will have to buff the finish down to the finish film that isn’t peeling. This will be tricky to do without removing the stain too. If it is just a couple of boards, maybe you can tape them off and just do those boards over.

Follow-up Q: The peeling doesn’t begin at the center of the board, it begins between boards where there is slight movement when the boards shrink in the winter. Only on some of the boards it spread from the cracks into the center of the board. Are you saying it’s common to see this issue at the cracks but if it spreads to the center it’s indicative of poor bonding? How can I tell if it’s just a layer of the poly peeling up or if its actually exposing bare wood?

Sorry for the persisting questions.

A: I wouldn’t say it is common to crack and peel at the edges. This could happen if there is serious shrinkage. The finish will only stretch so much and then it will fracture. But it won’t peel off the board unless there is a bonding issue.

Too thick coat of finish not drying

Q: Recently I restained our wood floors. Sanded, restained, then put poly on them. When we walk it leaves foot prints and there are some cloudy areas. What can I do to get rid of them

A: I’m not at all sure what is going on here. It sounds like a surface contamination. Was anything else wiped or applied after this work was completed? Perhaps something used on other wood work or furniture where a spray mist perhaps drifted down onto the floor? If that is the case you will need to use a cleaner to remove the contamination. Poloplaz has both a floor cleaner for general use and another for more serious issues called Tie Tac. If this is not the case and you have had no adhesion issues between coats, I would lightly but thoroughly sand down the final coat of finish, thoroughly clean up the fine dust and apply a thin coat with a roller using an excellent finish such as Poloplaz Primero satin finish.

Follow-up Q: When I put the final coat on I put it on thick and it seems soft as if it hasn’t cured yet. Will it harden eventually? Also it was a gloss not satin.

A: It will harden over time but I don’t believe it will ever be as tough as if you applied it at the recommended spread rate which is usually 500 sq. feet per gallon. I’d leave it for now and not even think of doing anything with it for at least a month. At some point later you may get a floor polisher and use 150 or 180 grit screens and buff it down really well before applying a thin coat. The edges will have to be sanded by hand. I use 120 grit for that on my hands and knees.

Follow-up: Thank you for the information. It has been a month but the weather has been all over the map. Hot cold rain etc. I will give it more time and then do as you suggested. Thank you again for taking time to answer.

Related Q: We put way too thick a coat of poly down on our refinished wood floor. It has been a week with the fan on it and it’s still not dry all the way through. The very top has set up but any weight and you sink down into the “un-set” part. Any trick to get this to totally dry?

A: Many finishes have a spread rate of 500 sq. feet per gallon. If you apply it at half that, 250 sq. feet per gallon, I could imagine it will take at least three weeks for this to harden enough to proceed. Lots of fresh air, warmth and time are all you have unless you want to sand it all off and start over. 3 Thin coats are always far superior than one thick one.

Polyurethane went bad?

Q: I had my floor professionally sanded, and then I stained it myself, and put a coat of water based poly on. Now the floor looks very dull and chalky. I waited 48 hours for the stain to dry before applying the 2 coats of poly. I did the same thing in another room 6 months ago, and that floor looks fine. I used the same container of poly. Is it possible the poly went bad in those 6 months?

A: I’m not sure. Is it possible when you first used the finish it wasn’t stirred up that much? I ask, because it sounds like now you have a lot of flattener in the finish making it appear matte.

All finishes have a shelf life of about a year. But it is my understanding that out of date generally affects the agents that control anti foaming and flow and not necessarily the integrity of the coating itself. You could try re-coating with Poloplaz 202, a 2 part water borne which has the cross linker built right into the finish so there is no product waste due to short pot life.

Follow-up: Thanks, I think you hit the nail on the head! I just finished applying a 3rd coat of poly out of a new container, and it already looks a million times better.

Chemical eating poly away; top coat of poly bubbling in two areas

Q: If a chemical eats through the top coat of poly would it also eat through the other 2 coats?

My hardwood contractor did a screen and added 1 coat of oil based poly to some hardwoods that were new in 2006.

There are two areas that have little bubbles popping up and you can scratch off to the next layer of poly. He believes this was something that was spilled or sprayed on after the re-poly and is eating poly away. Wouldn’t the chemical eat through all layers? Could this be caused by bubbles in poly or having heat on after refinishing?

A: I don’t believe this is caused by a chemical stripper. It could eat through more than one layer at a time, but regardless it does dry out and stop activating after a while. There could be some other contaminant on the floor, however, which is preventing proper adhesion on certain spots. Having warm air blowing directly on the finish when it has been first applied is not a good idea either and can cause bubbling because of the rapid set up and evaporation of the solvent.

Finishing hand scrapped floor

Q: I oil rubbed a hand scraped oak floor. The rough grain is dull, while the closed (smoother) areas are shiny. I need to make it look uniform. Less shine. Any thoughts? I am a flooring contractor, so I do have the equipment.

A: Well, of course the open grain, much softer than the surrounding wood will absorb more of any finish so you will require more coats. I would suggest going with a product such as Waterlox. You just mop it on with no need to wipe it off or buff it. It co adheres and builds.

Brazilian walnut finish is tacky

Q: I recently finished a remodel job on a one level home in Northeast Tennessee. The species of the wood is Brazilian Walnut. The troubles and learning experiences outweigh the cost of labor. The home had 1100 sq ft of pre-finished Brazilian Walnut in it already and I installed 300 sq ft of the unfinished. The pre-finished floors were 5/8 x 2 3/4 and the new unfinished wood I installed was over a sunken living room which I raised up to be level with the rest and made a picture frame design because I was unable to find the same floor. So the wood I installed is the 3/4 x 3 1/4 boards. Extremely heavy bundles! Sanding the pre-finished floors were impossible to do with the standard Norton Abrasive papers which were 36 grit. We special ordered the Norton Blaze and the Norton Red Heat and spent $480 on the paper alone and also added 35lb plate from weight bench set and tied it down on the Hummel. We eventually were successful in sanding the floor.

We put a sealer coat on, then applied a coat of Synteco 35 classic, matte finish. The next day I covered the floor to protect as I was finishing some crown, baseboard, and shoe base before the final coat. So a week later I finish the work, pull the paper up, buff the floor like I have always done for the past 15 years and applied the final coat of this tremendous product we use for the final coat. It is oil based and takes usually 8 hours to dry. I used to use Synteco for all coats even final coat but the fumes were starting to affect me and my cousin turned me on to this process of using just one coat of Synteco and using the Niles Black Bucket Super 95.

This process has yielded so many gorgeous floors and very happy customers. My problem now is, it’s now been 5 days since final coat applied and still tacky. I have learned the hard way about Brazilian Walnut. It’s definitely the toughest, heaviest and oiliest floor I have ever done. I’m wondering if I buff this floor eventually when it dries because it didn’t dry correctly and my roll marks are visible where I sectioned it off, which is the reason I love the final coat product, because how nice it evens out. Can I apply a water based finish if I get the oil based finish to come to a dust? The crazy thing is that the newly installed wood is flawless, it’s the pre-finished wood that’s still tacky. I have been looking for answers and solutions desperately, can you please help me?

A: I’ve not worked with Brazilian walnut (thankfully) but have worked with Jatoba. It was really heavy too. All these woods are oily. Poloplaz has one finish they recommend as a seal coat over these floors to block the oils. Prism is my memory is correct. Well, you are beyond that step now. It’s my experience that you can apply water borne over solvent or oil based. But you have to be sure all the solvents are out of the coating. I’ve had a few times where the finish appeared fully dry and ready for another coat. There was no tackiness. No heavy smell of solvent in the air. The finish powdered when screened. And when I applied the next coat, it wrinkled. Only a few times, but given the slowness in your case I’d give it extra time. Put some heaters or fans in the room if need be.

Prefinished floors are miserable to deal with because the coatings are abrasion resistant. The recommendation is to skim the coating with a 60 or 80 grit to break the surface. Then go to a rougher grit to flatten the floor and remove the rest of the coating.

Synteko! Oh man, I haven’t used those Swedish finishes in years. Very tough but the fumes are unbelievable. You could contact Poloplaz for information on a coating they recommend. Perhaps ask for Bill Jauernig. I use their Primero. The stuff is so consistent. I bet the floor with the boarder looked really good. I’ve only done a couple.

Finish feels like sand paper

Q: I just had my floors re-finished, and new one’s installed. The floors felt as if they had a fine layer of dust all over. And there were lots of sanding marks. The installer returned and tried again. The floors are definitely better, and brighter, but still feel like there is a fine layer of dust (like sand paper). There are still visible sander marks everywhere and it is not a glossy finish. What do I do? The are 3/4 Red Oak with a Swedish finish.

A: If you can’t live with the excessive scratches, the floor will have to be sanded and finished over. Swedish finishes are tough, but extremely nasty to apply, and also nasty to remove. The best chance of hiding any flaws is with a low sheen finish.

Similar Q: We’re moving into an apartment soon. We just got the keys and went by the place. They were supposed to redo the floors. When we opened the door, the floors looked wet. I reached down to check it. It feels like sand. Are there additional steps they still have to do to finish it? Or am I stuck with gritty floor?

A: Sounds like they used Hi Gloss and a lot of grain raise. The floor will need to be thoroughly buffed or polished with a fine screen to knock down this roughness. After thorough cleaning of the floor, another coat will have to be applied. They need to make sure their finishes are clean also. I now work out of gallon cans and after every job I pour the left over finish from a plastic bucket through a strainer and back into it’s original container.