Hi guys,

I've just finished sanding my first floor with the belt sander and edger and am in the process of sanding under the skirt board and cabinets by hand. Looking good so far!

According to my research after I'm done with the hand sanding I should use a floor buffer / orbital sander with a 100 grit screen and go over the entire floor. As far as I understand this is to blend the straight scratch marks from the belt sander with the round scratch marks from the edger.

However as I am going around doing the edges by hand I am eliminating the round scratch marks with straight scratches done by hand and they blend in with the belt sander scratches. So do I still need to use the buffer / orbital sander?

I will be using a dark stain afterwards if that makes any difference.

Thank you for your time guys, any advice would be much appreciated =)

I don't use a belt sander,just a drum sander. In the old days, using poly-urethane for a finish we never buffed the floor after the final sanding. We scraped and then hand sanded the edges to blend from the edger to the drum sander. Where we changed direction in the middle of the floor, we also hand sanded to blend where the machine changed direction. This may be the only place where a buffer saves time blending machine marks. Now we buff the floor with 100 grit screens. A belt sander can leave a more uniform scratch pattern and with good technique should not require buffing. If you are using a clear water-base finish you may want to use the buffer to go over the whole floor, just for piece of mind, since you will see machine marks and variations from the sanding process more clearly.
With all the special tools that are being used for floor finishing so they can save time, you have choices that weren't available 40 years ago.
If it is a small job it's sometimes more prudent to use more labor, if you can get down to do the work, than running out to the rental place. You should know how to make a stained floor look good by scraping and hand sanding, after the stain shows up imperfections in the sanding process, before the stain has dried.

Thanks again for the advice Pete =)

This is my first time refinishing a floor so I'd like to be as careful as possible and not leave out any steps if they are necessary. I will use the buffer if it will ensure a better finish, I will then be using a dark stain followed by an oil-based polyurethane.

My main concern was that I would actually get a worse finish by using the floor buffer as I have read that they can leave swirl marks as well. For sure there will be no swirl marks if I am finishing everything off by hand.

Also does a floor buffer (round body) and orbital floor sander (rectangular body) do the same thing? Or do you recommend one over the other?

If you like a dark stain you can pop the floor with water and after it dries, machine marks will disappear, unless they are very deep. The stain color will be pretty dark so test on a separate board.
If you buff with 120 grit to not have swirl marks, the stain will not take very well, unless you pop the grain.
Screens driven by a white pad will not leave bad scratches, but be careful with a brand new screen. Start in a corner, closet or area that will not be noticed, if you do use a screen. It can come out great without screening if you know how to prep the surface before staining. For a first time dark stain, I would suggest hand sanding with 80 grit with the grain over the whole floor.
Buffers and orbital sanders can both leave scratches that show when staining. Buffers will leave swirl marks. Orbitals leave pig-tail type scratches.
Popping the grain will bring out the texture of the wood grain on the surface. If you can get the desired color without popping the grain, that would be best.

Thanks again for the advice Pete =)

I actually did to a colour test on a couple of samples using the colour we selected and in the end we felt the non-water popped version was better. The water-popped sample turned out too dark and also as the wood we have has a very subtle grain, when it was water-popped the grain becomes even less visible (We want the grain to be more prominent). So one less thing to do!

I've decided I will use the floor buffer just to be safe, I really have no idea how well I have done with the drum sander and edger as it was my first time.

The only questions I have left are:

1. What is the difference between the round 'floor buffer' and the rectangular 'orbital sander'?
I've seen both of them recommended for screening.

2. I've noticed that after sanding some of the nail holes (only some) are filled. I think it is filled with putty. Should I remove these before staining? If so what is the best way of cleaning out the filled holes?
Pic of the filled holes on this link (they are the holes on the right) https://postimg.org/image/3w84ulr0l/

3. Some of the boards creak when stood upon. If I put my finger over the edge of the board I can feel that it moves down very slightly (a fraction of a millimetre). Could this movement damage the varnish once it is applied?

Thank you again for your time and valuable advice!

Your floor should be fastened down before you start to sand, The vibration of sanding rattles the board and it will bounce upward off the floor if it is not fastened well. This sands off more of the wood floor in the area of the loose board than is necessary. This results in wearing out the floor sooner than it should last.Top nails on wood floor are not the worst thing in the world. It is necessary sometimes. It will not damage the varnished surface, but can lead to white line syndrome with water-based finishes that are more flexible than solvent based finishes, as the finish will bridge between boards instead of break at the edges, leaving finish that is not stuck to anything and looks like a sheet of plastic between the boards.
I don't use a large random orbit type buffer. A regular buffer can save lots of time evening out some sanding scratches, but may show with a dark stain. If you want to have some insurance that your job will come out great, I would buff with 100 grit with a thin white polishing pad as a driver for the screen, and then hand sand with 80 grit, going over the whole floor, with the grain.
The buffer is harder to control in the beginning if you haven't used one before.

Hi Pete,

I've finally gotten back onto the floor after a busy period with work.

I'm currently hand sanding under the closet and skirt boards. FInished the entire perimeter of the room with 40 grit by hand and then with 60 grit to match the sanding sequence done with the machines (40/60/100).

However I noticed that after hand sanding with the 60 grit that the wood feels much smoother than the main area done with the drum sander at 100 grit. Is this normal? Have I 'oversanded'? (Is this even possible?) Or did I maybe overuse the same piece of sandpaper?

I wonder if this is why you recommend screening with the buffer at 100 grit and then going over the entire surface by hand with the coarser 80 grit? (Rather than also using 100 grit by hand)

In simpler terms, does sanding by hand produce a smoother finish than with a machine if using the same grit? (I would of thought it was the other way around!)

When hand sanding after the machine is finished you will be going with the grain. No diagonal or cross-grain scratches, so no swirls which will show up using a dark stain. Some machines sand one direction, back and forth, they are from car body repair and are air accuated. I doubt that you will have this available. Hand sanding with 40 grit is wrong. You will have trouble getting the scratches out with 60 grit and you only need to use 80 after the edger has finished with 100 grit. A scraper and 80 grit should take out all the cross-grain scratches and open the grain for a stain. You can make the floor too smooth from the fine sanding sometimes. This is where experience will save time knowing how to blend the whole floor absorption.