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Question:

Just got 300 square feet of 6" x 6' x 9/16" engineered unfinished maple hardwood strip for my living room (concrete floor..want to glue down, going to use Urethane - Bostik Best). I believe it needs only to be "screened" (lightly sanded?). Want to stain it a nice satin black. I read your article on staining...First, what type of sanding is involved and can this be stained with a water based stain? Do I have to stain twice, once with the water base and then with the varnish type for the pores? Any other tips you can give me on getting this floor stained right, (be specific)? Also, I'm installing this adjacent to Travertine. What type of separator can you recommend? I've seen a thin steel type, anything else?

J.P.

Answer:



Dear J.P.

You might change your mind about installing that floor, and then fine sanding it in place. Two thing can go wrong with the method you propose. Using a urethane adhesive is fine, but if you get even a smudge of glue on the surface of the wood, it will make a sealed area in that one spot. With only light sanding, this area will not absorb the stain at all, and you will only learn of this when you apply the stain. And by then, it is difficult or impossible to touch up.

The second problem, is that you must use dye stains for sure for the black floor you want, and with these laminated boards the stain will creep up the ends of the boards and possibly create a dark edge on all the boards. That's if you do the staining after the floor is installed. I will first address the methods when you do it YOUR way (hey after all you paid for it), and after I will give you an alternative method for the whole job. Hang on now here we go.

First be carerfull with this glue. Know it's "open time" and don't go past this or the glue will cure too early and the boards you installed in the dried glue will fail to stick. I hope this material is well milled, but if you find that some boards won't stay put use the 3M releasable tape, the Pergo floor ratchet or when really desperate use long boards on the opposite end of the room set against a tall board on the wall. Tap the long board down until it pushes against the floor board edge and the "wall board" (set on the wall studs with a blanket). You may find that with some stubborn boards, you will have to let them set overnight with the ratchet strap on before you can proceed with installing the next day. Take your time, even pros have a tough time with some bargin brand laminated wood floors.

Maple wood flooring is one of the most difficult woods to stain, because of it's flat, plain grain, it tends to blotch and streak. And it will show any sanding lines in the wood like crazy. So, I'm not really fond of just screening the floor after the installation. It may make circular marks in the wood. If this is really well milled wood, and the edges have fitted almost perfectly, consider hand sanding the floor with about 120 and then 150 grit floor sanding paper on a large flat sanding block. You might have to use a wood scraper to remove some of the over wood, but by hand sanding with the grain, you will create the smooth swirl free surface you need for dark staining this unforgivable wood.

If you wish to use a screen instead you will need to find and use 120 grit/ 20 mesh and then 150 grit/ 20 mesh screens and these will be tough to find locally. But the fine grit 20 mesh will leave the least swirl marks in the wood. Most rental stores only sell 16 mesh screens.

But if after installation you find the wood is irregular and bumpy, you WILL have to hire a professional floor sander to level the wood to 120 grit. And only a pro with his expensive 200 pound 3 HP machines can do this. You will have to hand sand and scrape out any errant edger marks, if he won't do it, this you can do. And you can read about these methods in how to do this in the article "How to Sand Floors Without Machine Marks". The advantage to having the floor professionally drum sanded, is that any glue spots will surely be removed, and the floor will be perfectly level.

Of course this sand on site method comes with a BIG warning. I only hope you bought a engineered floor that has at least a 1/6" top wear layer. Only these floors can and should be sanded level on site. Let me know.

So after the floor is sanded to perfection, apply a Black NGR dye stain to the floor. NGR stains have a alcohol or lacquer thinner base, so not only are they difficult to use, but very flammable and poisonous. You will need to use an activated charcoal mask, and be careful not to ventilate too much, or else even with this stain, it will lap mark and blotch. You may have to apply two coats of the NGR stain to get the wood dark enough. If you have gone overboard and the floor is too dark you can remove the stain with the same solvent it is mixed with. Be sure to find out what solvent this is when you buy it. Oh, and don't worry about the blue appearance of this stain, once you apply enough stain on the wood it will appear black. And once the final top coats are on they will be their true black color. Let these coats of dye stain dry at least overnight, and then apply another coat of a fast dry pigmented wiping stain.

The reason why you cannot apply a water based dye stain on the laminated wood is that it may curl and warp the wood. Especially if you have to apply the dye stain twice. And the water based dye stain will raise the grain and you don't have enough wood to deal with this sort of problem. Most NGR dye stains contain alcohol and only a little water, so it dries quickly and only makes the wood a little rough. And this little bit of grain popping is perfect for the added coat of pigmented wiping stain. Remember all the types of stains as reported in the article ?

You will find this method difficult and fume filled and quite a back breaking and fussy job. So here is the alternative. Make a large table of a sheet of plywood, and prefinsh the floor instead. Hand sand and possibly hand bevel all the boards in an identical manor. Make sure they fit well after you do this to a few boards. Use a small sanding block and bevel all four sides, as evenly as you can. Hand sand with 120 and 150, and then NGR dye stain the wood, twice if you want, and allow to dry and apply the fast dry wiping stain. You will have a fairly consistent coloring of the boards, but in either method beware of one thing. Then apply one of two coats of poly and THEN install the wood. After the wood is in place, screen gently and apply the final coat of poly on site.

The end grain of these laminated woods may still take the stain too intensively. You can either seal this small edge with de-waxed shellac the ends or use some solvent (for NGR) to minimize the end grain stain absorption.

If this all sounds a bit complex believe me it is. There are only about a half a dozen floor mechanics in any major city that can do this well. I'm not sure you are up to all this, but you wanted to know so I told you how it's actually done.

You can use the Goudey brand NGR dye stains by mail order them from General Paint and Mike Soutar Decorating at 516-985--6100. Goudey's also makes the fast dry pigmented wiping stain in the Black color. Be sure to use the full name of the finish, or else they will sell you something different.

Oh, and once the stain pigmented stain is dry, then you can apply 3 brushed coats of a oil modified polyurethane that has a UV blocker so that the dye stain doesn't fade. If you read my "Poly w/o the Bubbles" article you will see how best to do this. I would recommend the Deft brand Defthane Polyurethane Satin finish.

One last thing. I like to use the same wood (black stained of course) as the floor as reducer or bridging strips to other floors. If the other floor is 1/4" higher you should be able to buy a maple reducing strip to ramp down to the hardwood. If the floors are at the same level, this same strip is beveled on both sides and installed over the gap between the two floor. But the best way to go if the ends of the hardwood floor butts to the travertine is to butt them without a gap. But if the hardwood comes up to the tile on the side edge of the board, even with laminated maple (very very moisture stable) you should leave about a 1/2", which will have to be covered. I don't like metal strips over those gaps, they look cheap.

You may also find these articles helpful:

1. Floor Types And Finishes

2. How To Apply Oil Based Polyurethane WITHOUT The Pits And Bubbles

3. Custom Staining Wood Floors Without The Blotchy Effect

4. How To Sand Wood Floors Without Leaving Machine Marks

5. How To Take Care Of Your Health And Safety when Installing, Finishing, Repairing or Cleaning your wood floors