I have an OSB 18 and as mentioned, it really isn't designed to sand floors. It's meant to do final buffing/screening just before the first coat and can screen the coats of urethane . Actually, all I use my OSB 18 for is buffing out coats and I use a 220 grit screen under it.

Actually, a disc buffer while still slow , would be faster than an OSB 18. If you can get a disc buffer wit ha hard plate and some 36 grit paper, you will have a chance at sanding the floor.If you use the OSB 18, you'll probably pull all your hair out.

No kidding. I let two separate rental places talk me into the OB 18. I think it would take weeks to get down below the surface scratches and finish, based on my experience thus far in a 9X13 room. Getting the drum sander tomorrow. I will try it out on a sheet of ply or pressboard, first. And I will let all of you know how it turns out, and if a professional ends up being called in.

Thank you!

Mary

New question:

It looks like my floors are more uneven than I thought. I just spent 4 hours sanding a 9 X 13 room with the drum sander and 36 grit paper. I think I am finally through all the finish and down to clean wood (but I haven't done the edges, yet). It is going ok so far, but I imagine that it shouldn't be quite this slow (I have lost count of the number of passes I have made, but it was certainly over ten)...Am I okay going down to 20 grit paper for my first cut on the other rooms? There haven't been any major mishaps (yet), but I did uncover a stain on the floor (it seemed to be hidden by the existing finish).

There is one room that has new floorboards in it (it was linoleum). What grit should I start with on those? They seem pretty smooth.

Again, thank you for the help!

Mary

You know actually more about it than the guy renting the equipment which is not unusual. I own a Clarke American OB 18 and it is a great finish sander. When I was working at Home Depot I saw a lot of people come back pretty PO'ed after trying to take off finish with the Orbital Sander. They didn't talk to me first!

The reason the OB 18 isn't good for taking off finish is about PSI. The pad is 18 inches by 12 inches which is 216 square inches. If you divide 216 by the weight of the machine you can easily see that the sandpaper or screen is exerting less than a pound per square inch. A drum sander on the other hand is touching the floor with a space of 1/2 half inch by 8 inches or 4 square inches. This means you are exerting about 30 PSI on the floor. That is a huge difference.

I would recommend reading an article I wrote about using a drum sander titled, "How to Use a Drum Sander Without Killing Your Wood Floor" before you start your sanding project.

Hopefully your going to use an edger on the perimeter.

Hi,

I looked at that article; thank you. I had already started sanding with the drum sander, and I had practiced on a sheet of plywood, first. So far, no huge problems (couple of drum marks, but nothing that can't be fixed). I do indeed have an edger. I don't know when I will get to the edging, though, because it is taking a really long time to do the first cut with the drum (Clarke EZ-8) and a 24 grit belt. Here's hoping that the edging doesn't take as long as the drum!

Mary

The Clarke EZ-8 is a great little drum sander for homeowners. I own one myself for teaching people onsite. If you are renting equipment I would have suggested that you waited to rent it until you had the 24 grit drum sanding done first unless you had someone helping you.

Okay, new question:

I have sanded to 80 grit with the drum and edger, and things look okay, but I thought I would smooth it out with the OBS-18. However, when I turn on the machine, it won't go anywhere (i.e., it starts, but just sits there)! Why, and what do I do? I have a thick 1" pad and 120 grit paper on it (they don't have 100), and the paper doesn't seem to want to adhere to the pad. Could that be the problem? It is a pad that I used originally when I tried to remove the finish with the machine, so it is a bit dusty.

Mary

The sand paper not sticking to the pad could be a problem. This might be a little like the over the phone computer tech asking the user if the computer is plugged in, but did you remove the protective paper on the sandpaper so the glue is exposed? A dusty pad also can cause adhesion problems.

The OBS-18 does require a little push to move in the direction you want it to go. In some respects it is like a hovercraft. It is also possible that it is broken. It wouldn't be the first time a rental company sent out non working equipment.

yes, I removed the backing. I will try a new pad and paper. Now the problem is that I am having trouble finding new sandpaper, since I presume the stuff that didn't stick won't stick to the new pad.
thanks again!
mary

The place you rented this machine doesn't stock sandpaper for it? Home Depots that have a rental store rent and stock sandpaper for the machine.

Home Depot rented me the sander, but they were out of paper and singularly unhelpful about WHERE else I could go to get it. Anyway, the new pad and remaining papers worked okay, and I have finally finished the floor! One question: is it normal that it took me about 5-10 passes with 24 grit to get it sanded adequately (before moving on to the next, finer cuts)? I was afraid to take off too much wood, but it just took forever to get the old surface off and the irregularities (scratches, dents, etc.) mostly removed. Do you professionals have some magic way of doing this (or bigger or heavier equipment)? Just curious, since my way seemed very inefficient, even after I ditched the OB for the EZ-8.

I am posting a photo (5 coats shellac on birch, livingroom).

I really appreciate everyone's helpful comments and input.

Mary

Looks great. Yes our machines are generally heavier and also have more power. But I have found I have to frequently make 2 to 3 passes with 24 grit to flatten and strip floors.

Thanks!