Sanding Hardwood Floor

[Jon Middleton]

So, my flooring contractor turned out to be not so good. I can't do much about the installation, but am trying to put a nice finish on it. I need to put down one more coat, but need to abrade the last coat first. I tried to rent an American Sanders RS 16, which is one of the industry standard floor buffers on Saturday, but the tool rental guy at Home Depot told me it was the wrong tool and actually refused to rent me one. Apparently, they don't have the dust skirt for it, either. It's only about 300 sq ft, so I was thinking it I could get a really good ROS and hook it up to suction I could do it that way. I have the DeWalt D26451 single speed, but hooking it up to my Craftsman shop vac. Ideas?

[Neil Gaskin]

Go to a real rental yard and get a buffer. The ROS will work but be a pita

[Mike Cutler]

I rented one of the big square sanders from Home Depot when we did our floors. It was just like a giant palm sander.
Kind of the same story as you also. They had one of the orbital models, but the guy told me that unless you were experienced with one, it would leave swirls and scallops in the floor. I just changed grits between layers of finish, same as with doing a big table surface, and it worked fine.
That big square model took some time, but everything came out nice. It also had a DC hookup for a bag, that I connected to my DC.
I would not want to do an entire floor with a hand held orbital.

[Tom M King]

Best done with a buffer, and really fine disk, or screen. https://www.nortonabrasives.com/en-u...anding-success Most any dedicated rental place will have buffers to rent. Use a cleaning pad above the disk, or screen to make it easier on the floor.

There is no need to put anything more aggressive on it between coats.

Between coats, with a really fine disk doesn't put that much dust in the air, as most of it stays down on the floor. The buffer is pretty slow speed, so it really doesn't even throw it that far between coats. I like the Sand Dollar disks made by Norton (page 20 in the pdf linked below), for between coats, but they are not sold individually, as far as I know, and a box of them is fairly expensive. It would be worth asking at a floor finishing supplier, like Horizon Forest Products though. edited to add: It looks like they do sell them in smaller boxes now according to this catalog.

https://www.nortonabrasives.com/site...350.pdf#page=9

[Jon Middleton]

I bought the 3M maroon pad, which is 220 and was recommended by a flooring supply company and what guys use around here. Just need to find somebody to rent me a good machine.

[Tom M King]

That'll work. Buffers come in a variety of diameters, so you need to find one to fit your pad.

[Dan Schocke]

I just completed ~150 square feet of oak flooring using a Bosch 1250DEVS sander. I used it for all of the sanding from rough floor to finishing because the floor is in a foyer central to my second story, and I wanted to have good dust collection. Sanding the rough floor was painful, and it's not the right tool for that job, but for abrasion between coats it was really great. I used the 3M maroon pad cut down to 6" circle with 2 spots of 220 grit hook & loop paper to abrade between coats (the floor finish is Bona Traffic HD, and that's what the manufacturer recommended), and I slowed the sander to its lowest speed.

I plan to put hardwood flooring in a couple of bedrooms, and I'll definitely rent a drum sander to do the rough sanding for those. For the final sanding and between finish coats I'll likely just use this little Bosch sander again.

--Dan

[Tom M King]

It's easy to screw up a floor with the lightweight, rental drum sanders. For just a single room, or fairly small area, I advise to rent the big Varathane Random Orbit Sander that Lowes rents. It's a little slower than a drum sander, but almost impossible to gouge the floor. Go by their chart for how many disks to buy, and don't skip any of the grits in their system, and if you buy extras when you rent the sander, they can easily be returned for a refund when you return the sander, so you'll be sure you have enough to start with.

[Rich Engelhardt]

I have the DeWalt D26451 single speed, but hooking it up to my Craftsman shop vac. Ideas?

Let's get this straight.....

There's already at least one coat of finish on the floor right now right?
You just want to "scuff sand" the floor before you give it another - possibly final - coat right?

I used that exact same 5" DeWalt ROS you have to scuff sand three bedrooms, a hallway & living room between the third coat of finish and the last coat of finish back in 2009. I used about 6 disks of 220 grit & if I recall right, it took less than an hour to do all of it.
As Dan points out up above, for the final sanding a ROS does ok.

[Mike Wilkins]

In the past home I rented a large pad sander like one of the previous responders stated. I believe Lowes still has those for rent also.

[Mike Hollingsworth]

Water or Oil Finish?
If it's water you won't need to sand for a hook. Only enough to take out the imperfections you don't like.
If it's oil you'll need to sand with 220 for a hook. I do and found using a paint roller works great.
Either way, quarter sheet sander will work fine for such a small area. I use a Rotex.

[Jon Middleton]

Let's get this straight.....

There's already at least one coat of finish on the floor right now right?
You just want to "scuff sand" the floor before you give it another - possibly final - coat right?

I used that exact same 5" DeWalt ROS you have to scuff sand three bedrooms, a hallway & living room between the third coat of finish and the last coat of finish back in 2009. I used about 6 disks of 220 grit & if I recall right, it took less than an hour to do all of it.
As Dan points out up above, for the final sanding a ROS does ok.

Yep, just scuff sanding between coats. I didn't mind the ROS except it puts out a lot of dust. I tried the Makita B04510 quarter sheet orbital sander, which didn't put out as much dust but leaves more swirl marks. It only took about an hour, though. Rich, what did you do about dust control?

I won't be doing anything till I replace the transition boards that were gouged so badly (another bit of poor workmanship by my floor guy) between the kitchen and dining room. Figure I'll get that done first, feather them in, coat them a couple of times and then do the final coat for all of it.

[Jim Dwight]

I've patched the floor in our kitchen and I sanded and finished that area. We also scuffed the old finish in the kitchen and entry and put a couple more coats of poly on it before we moved in. That held up OK for a few years then we had the whole thing refinished.

I used a Milwaukee ROS, 5 inch, to scuff the floor and it went OK until it came apart. It had been used a lot. My 5 inch is a DeWalt and it works fine. I think it could do this. Mine lacks variable speed but I think that could be OK. I bought a Bosch 1250 DEVS more recently and would vastly prefer it. It has variable speed and is 6 inch. The turbo mode would not be useful for this but would be great if starting with a bare floor. It would probably help with your gouged boards. But if you are patient your 5 inch should do it.

I hired two flooring contractors for different areas of the floor. The first guy promised to show up 3 times before he did. He patched quickly and pretty well. His sanding resulted in flat floors but did a poor job on a hallway he couldn't use his big machine on. He also left a mess. So I left him off the list when I need the room we stored all the furniture in while the other area was refinished done. And I had him do the same hallway again. He did a little better on the hallway but still not very good. The big room the second guy did looks OK until the light is just right. The you see some waviness. I think he was going up and down very slightly with his big drum sander.

I did not see the first guys equipment (he didn't want me around) but the second guy had a drum sander that pulled 17amps at 220V. FAR bigger than anything Home Depot has. I think the first guys equipment was bigger but with no dust collection. They both clamped to the conductors in the panel.

I have one 10x12 bedroom and a hallway (not the same one) that needs refinished. It isn't terrible and the area is rarely used. The hallway isn't completely flat, it looks like it wasn't installed right or something shifted. I might just tear it all out and put down prefinished. That has several advantages including it doesn't stink up the house, allows me to address the area where the gap is big in the current floor, the prefinished is more durable finish. New floor would cost a little more but for this small area that is not a huge factor. Probably not an option for you. I've put down 600 ft2 or so of pre-finished so far in other areas of the house. It is not hard and I like the satisfaction of having a finished floor once it's nailed down.

[Tom M King]

I don't know why any pro would still be using a drum sander, unless they're keeping one for when they need to take a heavy, first cut. When I first saw a Hummel belt sander working, I quickly sold my drum sander in 1991. When I was building new houses, I found a young crew that would come sand my floors, and I would do everything past that. I kept my buffer. I conceded that I could never do as good of a job with even a pro drum sander (drum lowering handle separate from the machine rollers), and couldn't justify spending 10 to 12k on something I used a couple of days a year, so that was one of the very few things I subbed out when I was building one spec house a year.

I think the last time they did a floor for me was in 2010, but I always had several thousand feet to sand, had everything completely off the floor, so they could back up to the door, and go right to work. That year they charged me .75 a foot, worked into the night, and were done and gone when I got back the next day.

https://www.youtube.com/watch?v=JHDLgttr95E

If you're hiring a pro, they should have a machine like that.

[Rich Engelhardt]

Rich, what did you do about dust control?

I hung a damp towel on the exhaust side of a box (floor) fan on Low.
That caught probably 90/95% of the dust the sander put out.

When I finished sanding, I wiped the whole floor down with a water dampened towel/rags.
Scuff sanding between coats puts out very, very,very,very little dust.
If you're generating more that a very tiny amount, you're taking off way too much material.

If it's water you won't need to sand for a hook. Only enough to take out the imperfections you don't like.
If it's oil you'll need to sand with 220 for a hook.

Depends....all of the finishers are different.
Most of the WB's I've used will say you don't have to sand if you put the next coat on before 12 hours or something like that.
If it goes longer than 12 hours - or whatever the can says - then it has to be sanded.
Not that I've used all that much floor finish...but...just as an FYI.