Floor finishing question

[Dick Holt]

This may be a little OT, but floors are wood, right? I am in the process of refinishing my LR floor. It has been sanded and is ready to have the poly applied. Question is, how do I put poly on a fairly large floor (24' x 15") and keep a wet edge so there won't be any lap marks? I have purchased a floor pad, but have never used one before and I have to admit that I am a little (OK, a lot!) concerned about how the finish will look. I have put in a lot of work to get to this point and don't want to screw it up. Suggestions?

[Mike Hollingsworth]

product has a lot to do with it. You will know after the first coat. Clean Clean Vacuum Tack Rag

[Scott Holmes]

Dick,

Here’s how I do floors...
I usually cut the poly ~20% with mineral spirits to roll it. I usually buy the satin. It's difficult to keep the flattening agent well mixed when rolling, but it is much easier to mix it often than it is to buff the floor if you use gloss. I think floors look best satin to semi-gloss more toward the satin.

Don't forget to sand lightly between coats (120 grit on floors is OK) if you let it dry longer than the recoat time on the can. ~ 8 hours or so. Poly has a nasty tendency not to stick to itself or anything else very well so the sanding is for mechanical bond between coats. If you recoat too long after the recoat time limit.

Depending upon the size of the room, a 7"-9" roller that is 1/4" thick foam is the best way to poly the floor. You will need a brush with natural bristles and the roller; roll the poly on the floor in an area small enough that you can reach it all without any difficulty (say 1' x 3'); then using just the tips of the brush, which is dampened with mineral spirits, gently drag the brush with the grain over the area you just applied the poly, go slowly and the brush will pop 99.99% of the 2 million bubbles the roller left on the floor.

This process is called "tipping off". Repeat with the next section; continue until the floor is finished. Wait 6-12 hours; check the can for recoat interval. Repeat. Thinned finish will dry to recoat faster than the can says; so, as long as you can walk on it without leaving marks you're good to go.

Let the floor dry for a day or 2; then LIGHTLY sand with 180 grit sand paper, wipe with a rag damp with mineral spirits (paint thinner) Apply 2 more coats as above. The floor will "off gas" (smell) for about 30 days, less each day. A fan blowing on it will help speed the curing.

If you are doing a large area and you do not want to sand the whole floor; get 3 coats on approximately 8 hours between coats; then leave it 72 hours or more.

It is best if you can wait a week to move any furniture onto the floor.

[Sam Murdoch]

I can surely relate to your concerns. As Mike writes, the product has a lot to do with it. I have "professionally" finished 4 floors in the past few years, 2 with a tung oil finish like Waterlox and 2 with lumber yard bought urethanes. Mixed results . Happy customers in the end but a few floors were wayyyyyyyy more work than they should have been. So, yes, I relate, but this is what I learned - pretty easy to keep a wet edge on narrow boards - 2" to 4" using a good lambs wool applicator with either poly or tung oils.

It is easiest to pour a generous squiggly line of the finish along the full length of 2 or 3 planks in the direction of the planks and then with a wet applicator walk along and level out the finish - the entire length of the floor. DON'T - DO NOT take your finish from a pan (paint tray) on the floor and walk a wet applicator to your work. Every drip mark is a problem waiting to defeat your best efforts. The real pros will work with a helper. The helper is the designated pourer and your job is to walk along the floor pulling the finish level. Try to apply a good even coat - thick rather than thin so that each pass is flowing/overlapping wet on wet. On wide plank floors 8" or more this technique works only as well as your applicator is wide.

A few other cautions:

1) Work in a cool room if you can and best not to have lots of airflow as you work. If you need to run fans to ventilate best to turn those on after the finish is applied.

2) For poly in particular that dries fast compared to tung oil you don't want to use a roller as air bubbles never really dissipate. (Unless you use Scott's tipping off method as noted above - while I was writing)

3) The lambs wool applicator should be wet with solvent or water for a water based poly, and worked well with your fingers or a stiff brush to pull out any loose fibers before you get into the finish.

4) Of course, plan your exit strategy .

5) Finally, don't be frenzied. Slow and steady is a good approach as long as you have thought through the process and maybe even practiced a dry run.

Good luck. Maybe some real pros will chime in here before you begin for extra confidence or confusion.

Sam

[Pat Barry]

Would the techniques described by Scott and Sam also apply for refinishing a engineered floor? Floor is approx 5/8 " thick, with a top layer of approx 1/8 to 3/16" thickness. I was told when we bought it 12 years ago that it could be "screened" 2X. The floor could use some help, particularly around the patio door area. I was leaning towards a poly finish and appreciate Scott's comment about the satin finish for flooring. I think gloss might be too glossy but I didn't think the satin finish would be robust enough (don't ask me why, just don't recall seeing satin listing floors on the can).

[Scott Holmes]

There is no difference in the performance of the gloss or satin finish only the sheen is different. Engineered floors (prefinished) are usually finished with an extremely durable 2 part conversion varnish.

You will need to scuff sand it after cleaning it very well, to get the poly to stick.

[Sam Murdoch]

Yes to using these techniques on such a floor. As to the preference for satin or more sheen - the caution with satin is that is has flattening agents which must be kept properly in suspension as you apply the finish. To quote Scott: "It's difficult to keep the flattening agent well mixed when rolling, but it is much easier to mix it often than it is to buff the floor if you use gloss. I think floors look best satin to semi-gloss more toward the satin." Semi- gloss is OK too if you aren't talking about a brightly sun lit room, but I'm inclined to agree with Scott that a satin finish on a floor is preferable. That's just a question of taste.

[Scott Holmes]

To clarify my comment on keeping the flattening agent in suspension...

When doing floors, my wife usually does the roller part and I tip it off. I encourage her to get the roller down to the bottom of the pan to keep it mixed.

Most often when I need to do a floor I have the store put the poly on the paint shaker to ensure the satin is well mixed. I even had one big box store employee tell me "he could not put it on the shaker"... I ended up having to tell the manager that I was "spraying it" so he would shake it for me.

[Dick Holt]

Thanks for the info guys. I have not decided yet whether I will roll and tip off with a brush or pour and use a pad. I have the supplies to do both. Guess I will have to decide by tomorrow (Sat.) since I will be starting then. I may start with one method and then switch if I don't like how it is going. Thanks again for your help.

Dick

[Rich Engelhardt]

(misery loves company!!)


Roll and tip = standing up to roll, then getting down on all 4's.
Pour and applicator pad = standing up and using an extension pole.Plus some down on all 4's with a brush.

I find as I've gotten older that, while the spirit is willing, the kness and the rest of me is unable to do all the up/down stuff without it really taking it's toll.
The first thing to go out the window is any sort of thought of "quality of finish" when the fatigue takes over. My only thought is to just survive long enough to finish - no matter how good or bad the appearance.

I have three bedrooms, a living room, a hall and a dining room to finish today and over the course of the next few days. The sanding-of-the-floors ritual kicks off an about a half hour from now. (No - make that an hour - can you tell I'm putting off picking up a two hundred pound sander and unloading it from the van by myself?)

Since I need to use some Seal Coat to seal in some pet odors, I'll be using a brush on the whole thing first.
I may just use slap some knee pads on and brush the finish on also.

There's really no right or wrong or best way to apply a finish to a floor so long as the desired outcome is achieved.

Just follow the drying times and procedures on the can and you'll be fine.
I've lost count of the number of floors I've done.
Satin is the way to go if you're not experinced. It's much more forgiving w/respect to surface blemishes.
A lone speck of dust in the middle of a gloss finished floor sticks out like a sore thumb.

(I'll hoist a cold one for you in about 6/7 hours when the sanding is done and the sucking-up-of-the-dust ritual begins....I'm, figuring this is going to be about a twelve pack project )

[Dick Holt]

Rich,
I hear ya! My new best friend is the giant economy size bottle of ibuprofen!!!!

Dick

[Rich Engelhardt]

So Dick - - how'd your floors turn out?


Mine ended up about half sanded after 12 hours... .
I got the 40 grit sanding done and the living room and dining room done with 80 grit.
I still have 3 BR and a hall to 80 grit, and the whole thing to 120 grit.

LOL! & yes - Saturday was a 12 pack kinda day .

I told the guy at HD when I returned the sander Sunday morning, "I've been divorced, had a kidney stone, an IRS audit, a root canal - - and I've used THAT (pointing to the sander)."
He just chuckled,,,,

[Scott Holmes]

I've polyed many hardwood floors that were sanded no finer than 60 or 80 grit. As long as there are no cross grain scratches you will not see a difference when you are finished.


If you get a helper to roll the poly on the floor and you tip it off; you will not need to get up and down and it will go pretty quickly.

[Rich Engelhardt]

Scott,
I'm going to have to stain the floors & I'm afraid there might be some swirls left by the sander that I can't see until they show up with the stain.
I used a U-Sand on the floors - which is a big giant ROS w/4 6" disks - not a drum sander.
Being a ROS, it does go cross grain.

My wife is the hired help....
She's gotten to be ok with some things,,,but,,,rolling the floors isn't something she's quite ready to tackle.

[Scott Holmes]

Make sure you get rid of cross grain scratches if you plan to stain. You can still use 80 grit just use a belt sander or in-line sander. If your wife has ever used a roller on the wall; doing the floor is easier. She just spreads it out with a foam roller you tip it off.