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.

Polyurethane peeling in some of the joints

Q: We had our hardwood floor sanded, stained and polyurethaned in May and now in March (less than a year) they are peeling in some of the joints, and the joints are now white in color. what would cause this and how is it fixed?

A: There are so many possible causes for this, without knowing what finishes they used, how they applied them, and a host of other elements I can only wager a guess. It sounds like during the heating season your floor, because of low humidity has shrunk a bit, and the finish cracked on the joints. The peeling is at the joints, not over the entire floor.

The fix is to have the floor buffed really well, paying close attention to board edges and apply another coat. Any gaps should be filled first. Try to keep a relatively stable relative humidity in the house.

Similar Q: I just had my 14 year old wood floors sanded and stained, and 3 or 4 coats of polyurethane applied. There is now peeling at the seams where the boards come together. The floor guy says it is because the floor gives when you step on it. Could that cause the peeling?

A: If there is significant flex the finish will stretch and then break and perhaps chip, but not peel. In my opinion a more likely reason for peeling on board edges would be contaminants such as wax bleeding up from between the boards, or if there is a lot of movement from one board to the next, the mans polisher probably went over top but missed abrading those edges and he hasn’t gained adhesion.

(After further correspondence…) 3rd A: The problem I am having with their explanation is that you can pull the finish off in the middle of the board with a piece of scotch tape. This is totally unrelated to the movement of the boards and would seem to indicate lack of adhesion in general across the floor. I have seen tape pull of the top layer of water borne, but I’ve never seen it happen to oil modified. However, when it happened it was because the workers taped the floor around the perimeter of the rooms soon after the coating was applied (not cured) and it was in place for days before they started trying to remove it. It wasn’t a case of applying a piece of tape and then pulling it off right away with the floor finish stuck to the tape.

I can’t question the ability or integrity of the company who did the work. After 35 years I know sanding, staining and finishing is so hard and technically difficult, sooner or later a job will go south. I would think that if they care about you, their customer, care about the type of work they do, and want to have a good reputation, they should try and make this right even if it means starting over. That really seems like the only option to fix this. Putting another coat of finish over top of one that is not adhering is not going to fix the problem.

You would probably be well served if you could find someone local to provide you a second opinion with a home visit.

Similar Q: What can be done about white lines in between boards of Walnut wood flooring?

A: Difficult to say. What caused the white lines? If the boards shrank and stretched/cracked off the finish you will need to control the environment and humidity or lack of it. A buff and re-coat may get rid of the lines.

Will applying additional coats correct fish eye bubbles?

Q: We attempted to apply a top coat of polyurethane on our old floor with a roller. It is full of bubbles. Will applying additional coats correct this?

A: You will have to rub this coat down really well to knock off the bubbles, especially so if they are fish eye type. Some finishes roll on very well but you must make sure there is no air movement across the floor for several hours after applying the finish so that it doesn’t set up too quickly and allows the finish to flow out smoothly.

Similar Q: Why does our floor have bubbles between most of the floor boards, after it was recently refinished?

A: Is this just bubbles or actually beads of finish on board edges?

Bubbles can appear if the solvent is evaporating too quickly. This can happen, for example, if there is a sky light or a lot of window exposure with direct sun light heating the floor. Best to cover the windows while coating.

Polyurethane coating is flaking

Q: We have a guest house with pine floors. I have sanded them, applied and oil base stain, then went over them with a polyurethane. I applied about 4 coats of poly in 7 days time. The floors looked great for about a month (they weren’t even walked on) and we had a cold snap in weather. I noticed my floors had almost a frost look to them and they were flaking like crazy. Can I just buff the floors with a screen and redo the poly in a day instead of a week? I am learning that I should not of let them dry that long between coats. The floor scratches like crazy.

A: If the coating is flaking seriously you will have to start over. It’s likely you have flaking between all the coats between the first and second all the way up to the fourth. What you have here is lack of adhesion. Adhesion is attained between coats by applying a coat of polyurethane, allowing it to dry and then thoroughly buffing or abrading the coating with a fine abrasive. Essentially you are applying a fine scratch to the finish to allow the next coat to grab. This has to be done between each coat. You will know if a coat of finish is dry enough to proceed if it turns to a fine powder as you buff it and you aren’t having the finish roll of in little strings or clogging the abrasive. 3 coats of finish initially on a stained floor is plenty to start with.

Follow-up Q: Can I do this with just a screen buffer? I am thinking that a sander is to much. I don’t want to pull off the stain.

A: You can certainly attempt it as a last ditch effort before going the extreme but necessary route of total resand. The difficulty is you don’t know for sure on where the peeling starts. Is it failing from the second coat up? You will likely have to screen it fairly heavily, removing a lot of the finish and so there is a very real risk of cutting into the stain with the screen.

Related Q: We have white lines where the polyurethane looks like it is flaking off. The floor was stained with Miniwax and an oil based polyurethane. The main areas of stain were applied at least five days before any polyurethane was applied. The polyurethane was applied in three consecutive days. We have been using a cleaner that contains ammonia and washing the floors every two weeks. Could this have caused the white lines? If not what could be the cause?

A: It sounds clearly to me you don’t have adhesion between coats. This is achieved by thoroughly buffing each coat, that is scratching and deglossing prior to applying another coat. It is really a mystery to me why you waited so long to start applying the finish coats on the stain and why you would be using such a strong cleaning solution in the meantime. Preparation is everything. Clean environment. Good temperatures. It seems clear to me this has not been professionally done.

Finish bubbling in darker spots of exotic wood floor

Q: We had a pre-engineered Brazilian Mahogany floor installed circa 2004. We started to notice dull spots and tiny bubbles in finish over time, but only evident where wood has darker colors. I brought it to attention of manufacturer, and they admitted it was product defect. (They provided cash settlement!) I experimented with one board that was badly bubbled.. sanded out bubbles, recoated with poly. In 6 months, finish is again loaded with tiny bubbles. If I have floor sanded and refinished I fear the problem will recur. 95% Of floor is unaffected.

I wonder if I should have the worst boards replaced with lighter color boards and be done with it, or do that plus refinish?

A: I sounds like an abundance of oils in the wood causing this issue. There are water borne sealers and finishes which are advanced as excellent blockers for oils in exotic woods. www.poloplaz.com has at least one such product they recommend. If course, it you have some boards left over it would be less expensive and far less disruptive to simply remove the offending boards and pop in replacements.

After three months finish started to blister

Q: A floor contractor sanded our oak floors to the bare wood and finished them, leaving a lot of small grit and hairs under the finish, so he redid the floor, and it looked even worse after. On the third try his job satisfied us. He used an oil coat of some type and a water based poly for the final coat. I am not sure what his exact process was.

However, after three months the finish started to blister, mostly starting in the cracks between the planks. This is happening throughout a very large area in several places. What would be the correct way to fix this problem? Our General Contractor wants to have it buffed and one coat applied. Does this make sense?

A: I suspect the first coat he applied went between the boards and didn’t dry. Is this blistering or tiny beads of polyurethane? If the latter, this condition is known as poly beads or poly balls. You may have to keep scraping it off until it finally dries and stops.

If it is actual blistering, you likely have a reaction between the incompatible solvent in the initial coat (mineral spirits) and the water borne poly. In that case you may have to sand yet again. A clean environment and clean finishes are imperative to provide a good looking floor.

Fisheye and many rough spots after finishing

Q: We had our 48 yr. old oak floors refinished by a pro, sanded to bare wood and 3 coats of oil base satin poly. I complained that there were many very rough edges and swirl marks from the buffer, so the pro then buffed and did another coat of poly. This time with a different brand, Fabulon, oil also. (Not sure what brand the previous three coats were.)

While applying the 4th coat he started seeing what he called fisheye, spots where the finish didn’t adhere well. He buffed and did a 5th coat, not as bad, but still some fisheye and many rough spots. I don’t think he tacked with mineral spirits after buffing, would that help prevent fisheye? Should he use a finer screen to prevent swirls and rough spots? Thanks.

A: Everything we do when sanding and coating floors involves scratching the wood and the finishes to gain adhesion. The aim is to make such scratches fine enough that they are not visible from a standing position. I’m surprised you could see swirls through the satin. I wouldn’t use a screen any rougher than 180 grit when buffing between coats, and prefer to use even finer 220 when possible but that depends on how hard the previous coat is when I buff it. There are also newer abrasive pads created because of the swirl issue. 3M makes a maroon pad which can be used with 180 grit sanding strips and now Norton Abrasives has created a line of abrasive pads which promise not to leave such marks.

I always vacuum then wipe the floor down with a micro weave mop before coating. Wet or dry doesn’t matter. All air movement should be prevented after application so the finish will have time to smooth out before setting up.

Similar Q: Is there any other way to get rid of the tiny air bubbles in my floor besides another coat of poly? Can I sand them with 220 grit screen and then apply a wax to bring back the finish?

A: You will need to abrade the surface coating to knock down the bubbles and apply another finish coat. Make sure no air is moving across the floor while it sets up. I definitely would not recommend applying wax over this top coat. It will be very slippery and impossible to keep clean.

Lines and streaks in tung oil finish

Q: We have an old home that needed new floors. We decided to put down pine, wide plank floors. They are very beautiful, but the manufacturer had us use tung oil on them. Through the process I found out there were two types of oil: one goes on first and one goes second. Well, by that point, we had started putting the second one on before we had two coats of the first. We then just had to go with what we had done.

The problem I have now is that the floors are uneven in color and you can see lines and streaks in the floor. Not to mention they are impossible to keep looking clean. You can see every footprint and so on. What can we do?

I would like to try and go with urethane. We have been told we can put it over what we have. I am scared to death to make a move and ruin them more, or worse.

These floors took well over half of our budget and they look terrible.

A: I would have someone come in, polish them with a fine abrasive and apply a couple of coats of polyurethane. Tung oil, in and of itself, isn’t a practical finish for a floor. If you had used Waterlox which has tung oil as one of the 5 main ingredients you would have had much better results.

Unfinished bald spots in several rooms

Q: We have just bought a house and had some new wood floors put down. We showed up the night we were allowed to walk on the wood, to inspect the job. We have found about 12 bald spots in several rooms, as well as a square nail back sticking out of a board in the middle of our dining room. I called the contractor and he said he’d saw the nail and will sink it and cover with putty. He couldn’t believe we saw bald spots (some 5 inches long). He says he’ll just patch them up and it’s no problem.

I feel we have a big problem. Should we insist he polyurethane the whole floor over again and move in later? If so, how many coats should we insist on? I don’t want these floors to age prematurely because they have too thin a coat. Also, I can feel the grain texture over multiple areas of the floor, which makes me think the poly was put on too thin. It is suppose to be 3 coats now.

A: It sounds like the floor needs to be buffed down and another coat of finish applied. Most coatings have a spread rate of 500 feet per gallon. Given so many spots he missed with the finish, I think a full buff and coat is really the only way to fix it up. Buffing with a fine abrasive should knock down any rough spots or grain raise.

Related Q: I had my oak hardwood floors sanded down and refinished with polyurethane (oil). I’ve noticed that some spots along the walls have been missed during the finishing part with polyurethane. It looks a bit dull in those spots. Would another coat fix the issue?

A: Yes, another coat will fix the missed spots but the floor will have to be buffed down again to make sure you have good adhesion.

A few spots poly will not stick to

Q: I have been using oil based polyurethane to finish a bar top. I have 6 coats of poly over 1 coat sanding sealer and one coat stain. There are a few spots, one is about the size of a dime, that the poly will not stick no matter what I do. I have tried sanding just in those spots a little more than the rest, between the coats of poly, but it doesn’t make any difference in how the poly sticks.

What really confuses me is that the rest of the bar, the sides and the arm rest, do not have any of these spots, it is just the top. Do you have any advice on what to do to make the poly stick to those spots?

A: I would think this has to be caused either by some sort of extractive in the wood itself or a contaminant on the bar top from outside sources which hasn’t been removed. Try wiping the spot down with denatured alcohol to remove the contaminant. Or apply a small amount of de-waxed shellac (Zinsser seal coat) to those areas where this is occurring.

Finish eroding in a bubble-like pattern in some spots

Q: We have a four year old floor and around the fridge and some cabinets we have found places where the finish is eroding in a bubble-like pattern. We just had the whole floor refinished and that day the bubbles returned. They are not like air bubbles but are the same shape. What are they and how do I get rid of them?

A: My guess is that when the floor finish was applied the fan on the refrigerator started to blow air across the floor, causing these “fish eye” bubbles to form. The only thing that can be done is to rub them down with a fine abrasive and apply a fresh, thin coat of finish to the entire affected board.

Removing sealed grit from finish

Q: I have a BR 111 Triangulo Santos Mahogany wood floor. I use Bona Kemi products on the floor, which are safe. However, I put the refresher on the floor with a less than clean rag and ended up sealing grit, etc., in the floor. Is there a safe way, below hiring a professional, to take the refresher off and begin again?

A: I have not used their refresher product. I would suggest lightly abrading the coating with a 3M maroon pad, clean it well and re-apply according to their directions.

Finish peeling in sporadic areas

Q: The old owners refinished our floor but they are peeling, in odd and sporadic areas all over the house. Can the areas be fixed or do I have to redo all the floors?

A: I would definitely recommend a complete re-sand and finish. You are either dealing with a contamination issue between the coats of finish, or improper preparation between coats to ensure adhesion. What you apply on top of this now will only be as sound as the coatings it is sitting on, which by your comments is not stable, but peeling throughout.

Peeling off someone’s hack job coat of polyurethane

Q: We recently bought a small condominium that has an engineered (5 layer) maple hardwood floor. Someone attempted to refinish the original satin finish with a high gloss polyurethane. The shiny top layer is peeling off in sheets all over the floor. My question is, is there any way to “buff” off the shiny coat and get back to the original satin finish WITHOUT having to sand and re-finish the entire floor? The places where the new shiny coat have peeled off reveal a perfectly fine original satin finish which is what we would like to get back. Thanks.

A: I can’t see buffing this off. For example, if you used a car paint finish buffer you would face the risk of flakes of polyurethane getting under the pad and scratching the original finish. Unless you can patiently peel off the gloss coating a situation like this generally requires totally sanding the floor.

Pit marks after buff and coat of prefinished floor

Q: I had a 10 yr old glossy Bruce 3/4″ prefinished hardwoood floor screened and buffed a satin finish, now it looks and feels like there are pit marks on the floor. What could this be from and can it be fixed?

A: It is very difficult to impossible to adequately screen the coatings on these floors given their abrasion resistance. This is why a chemical treatment has been developed to gain adhesion. So I would be concerned about this coating peeling off at some point. What this pitting is I don’t know. Was the floor not thoroughly cleaned before the finish was applied?

Follow-up: I don’t know if it was cleaned properly. The same company did the same procedure, screened and buffed, three other rooms in the house and they all came out awesome; the difference is they were not prefinished.

Since the room involved is my daughters and she just moved back into it, she does not want to go through the aggravation of moving out of the room again, so will live with the floor as is for now. I guess it can be called the distressed look! Thank you for your reply.

Delaminating finish and stain coming up as well

Q: We bought a foreclosure a year ago which had lots of urine stains on the wood. The flooring contractor sanded everything down and patched where needed. The bare floors looked great. We had them use a dark stain and gloss water based poly finish. Again, everything looked great when done. A couple weeks later, we noticed a small round spot where the poly had come off. More spots appeared over the next several months. In most cases, the stain seemed to come up as well. Some spots were tiny, some up to 1 1/2 inches, mostly round but not all. They sanded the floors down and redid everything. 2 Weeks later, I’ve found 2 spots where it is starting again. What could be causing this?

A: This is very strange. Delaminating finish is one issue which can be explained by some type of contaminant on the floor or between coats which prevents adhesion. Stain coming off too is a different animal altogether because the stain does penetrate into the wood surface a little bit. It isn’t just something that sits on top of the wood like a coating, unless he used a tinted polyurethane. Can you tell me what stain he used?

Follow-up Q: Unfortunately not. When my contractor went to have the floors redone, the sub claimed not to have a record of the stain used initially. It was not a tinted poly. It was supposed to be two coats of ebony stain (brand not known), but we found a plain silver can afterwards that had written on it “plus 12 oz. black”. When they redid the floors, the color came out much lighter. My contractor had scheduled a different sub to come in and strip them down again and try to get the color right, but now we have these spots coming up again and don’t know what to do to prevent that. The original contractor argued that some outside contaminant might be being brought in either on our shoes or the dog’s paws. While the ongoing nature of it and the fact that the spots are mainly in traffic areas would tend to support this, the fact the most of the spots were perfectly round doesn’t, plus I don’t know what we could be tracking in that could do this. We don’t have any contact with anything that caustic or acidic. Also, there have not been any problems on the stairs, upstairs, or master bedroom, which are all entirely new wood. Is there anything they could have used on the old floors that would cause this?

A: While I’m not suggesting this caused the problem, I’m not a big fan of applying two coats of stain, especially when using very dark, heavily pigmented stains with more pigment added. If I want to achieve a darker version of the colour I will water pop the floor, which simply means wetting the surface and letting it dry to open the surface and allow better penetration. I tend to think as was mentioned, that a contaminant is being introduced. I was called in to refinish maple floors that somebody made a real mess of. Everything I did looked excellent until I applied the finish which still looked amazing except in areas where the finish was being repelled. The home owner turned his garage into a Harley man cave with plastic tiles on the floor. I walked back and forth constantly over this floor to get to my trailer. I asked if he treated these tiles with anything. Yes, Honda spray. And he had renewed the spray two days before I started work. So, that was the culprit. I was able to polish the floors, wet buffing with Poloplaz Tie Tac which removed the contaminant. Then I screened a recoated. I’m no so sure this will work for you because in this case your finish is peeling off. In my case the finish was repelled and didn’t form a film over the areas of contamination.

Follow-up Q: So that was something that was being tracked in during the refinishing process before the poly was applied?

They are talking about something being tracked on an ongoing basis after everything was finished. That’s part of the issue – that the de-lamination has gone on over a period of months. What type of situation could cause that?

A: When the finish is delaminating and pulling away from what is beneath it, clearly contaminants on the surface are irrelevant. The problem is what is beneath the finish. Someone or something could have walked a contaminant across the freshly sanded floor or over the stained floor before any finish was applied.

Another possibility I thought of as the previous email was leaving is the slight possibility, if the workers who did the job wore knee pads that had something on them. But you say two different crews did the work with the same results so this possibility is stretching the limits of probability. I generally try to look for the simplest, most obvious explanation first: something finding it’s way onto the floor before the finish was applied. That contaminant could be the heavily pigmented stain itself, especially if they used a water borne finish and the stain was not 100% dry. The solvents from the stain would not allow adhesion.

Tons of little scratch marks on wood floor

Q: Hello, I recently sanded down to bare red oak floors Wednesday. I put down the first coat of oil based high build gloss poly Wednesday night. All looked decent. I did a light sanding with 150 grit this morning and cleaned and re-coat. I look now and I see tons of little scratch marks all over. I do not know what to do at this point to get rid of the scratches if anything. Please help. Thank you.

A: You will need to buff it all down and apply another coat. I would recommend a lower shine, say satin which looks very nice and is easy on the eyes. Gloss is particularly unforgiving when it comes to things like little scratches.

Follow-up: OK. Thank you. I was going to use 220 grit in Palm sander then reapply with satin.

A: You should be fine. Just make sure you thoroughly buff the entire floor. 220 is more than fine enough. I often use 180 grit with no issues.

Follow-up Q: Okay thank you. Is buffing different than sanding using 220 grit sandpaper?

A: Not necessarily, though sanding generally can invoke the idea of removing all finish to clean wood. Buffing or lightly sanding with the intent of scuffing or scratching the existing finish coat to gain adhesion is what we are aiming for. Accomplished with the finest abrasive that will do the job, thereby minimizing visible scratches.

Related Q: Hello. We at redoing our hardwood floors for the first time. After sanding and cleaning we applied old masters penetrating stain with a rag. Then we applied satin polyurethane with a brush. After the poly dried we noticed several little bubbles that we sanded down with 120 grit sandpaper. Now we have sanding marks all over the floors and I am worried that if we apply another coat of poly the marks will show through. How can we fix this before we put another coat of poly on? Thanks!

A: When applying more than one coat of polyurethane you must sand or buff between coats with a fine abrasive to gain adhesion between coats. So scratching is part of the process. The idea is to have scratches fine enough that a good finish will cover and hide them. After thoroughly buffing the entire floor, being careful not to cut into the stain, clean up and apply another coat following the spread rate of the finish which is generally 500 sq. feet per gallon. You may want to use a top quality finish such as Poloplaz Primero satin. It’s is a great product to apply with a 3/8 or 1/4 pile roller.

 

Black spots appearing after refinishing

Q: I just had my oak engineered floors refinished by professionals. Everything looked great. Days after black spots started appearing in one room. The spots are getting bigger and more are appearing each day. This room is on a second floor, so no water problem.

A: I can only make a guess on this. It sounds like water but as you say water is not involved. Then I would suggest a fungus, probably present right from manufacturing. Perhaps they used a water based finish which re activated it. I would call the guys back and have them assess this. You can also contact the National Wood Flooring Association who do have inspectors. They also have a huge repository of information and have likely come across this issue before.

If you take this course, I would be grateful to know what is concluded.

2nd Coat of polyurethane rough and grainy

Q: We sanded, stained and oil based polyurethaned a wood floor with 2 coats. We did not sand between 1st and second coat. 2nd Coat dried rough and grainy looking. We sanded second coat. Smooth but still grainy looking. Do we need to start over? All 5 rooms look like this (put 1st coat down day 1 and put 2nd coat down the next day). Have not applied 3rd coat. Can this be fixed without sanding down to bare wood again. Would attach picture if I could.

A: Roughness can be caused by rough preparation in sanding, grain raise or debris in the finish for example. A light but thorough sanding with fine abrasive should take care of this issue. The floor needs to be completely vacuumed and wiped down to remove all dust and debris. I’m not certain what you mean by grainy. I’ll take a guess. If you are working with oak for example that has a heavy grain pattern the finish will soak into that much more than the surrounding wood. The grain is much softer. Finishes have a spread rate they should be applied at, generally about 500 sq. feet per gallon. Applying thick coats is a bad idea. The heavy grain is really part of the wood species. If you are trying to duplicate the look of a factory finished floor where they boast multiple coats of finish, don’t. The process is much different and all done by machine.

One more coat should make a difference if you follow what I said above. I wouldn’t use rougher than 120 grit to rub the edges. If you have access to a polisher, I would try 180 grit screens and work down if you need to. Be careful not to cut through and remove the stain.