How to Refinish a Hardwood Floor

Edge Sander

Used to sand to the edge of the wall.

The large orbital is better for light removal or simple surface prep. However, you can use this machine if the drum sander just seems like too much to handle. Just use a lower number (36 or so) sandpaper.

Sanding Direction

Unless you are sanding the edges where the wall and floor come together, you always want to sand in the direction of the grain or plank. The only exception to this is if you create a gouge with the drum sander. In that case sand the gouge at a 45 angle to the planking.

Unlike the drum sander gouges are much less likely. It's also an easier machine to operate as the orbital action cause the machine to "glide" over the surface of the wood. With this type of tool your technique is not as important, but you still want to sand in the direction of the grain of the wood and you always want the machine moving as it's running.

Corner/Detail Sander

Used to get into the corners where two walls come together at a ninety degree angle.

Notes on Sanders

The rented sanders (drum, large orbital, edge) have some particulars about them that you, the renter, should be aware of.

Large Orbital Sander

Moderate removal and large area.

Edge sanders go through paper slightly faster than the two above. It's also a heavy machine but nowhere near even 25 pounds. Still it's a good rental option if you want to get the floor ready for stain or be able to stain and seal in short order.

The orbital sander weighs about 120 pounds. As with the drum above you'll need a helper if you are sanding above the ground floor just to lift it. The paper is quite large (roughly two by three feet) and you'll be able to sand quite a large area before having to replace the paper. Paper replacement is very easy. Cleaning this machine will also help you avoid a cleaning fee upon return.

Large Drum Sander

Rapid removal and large area.

There are four types of sanders for various amounts of removal. The "big gun" is the drum sander. This is the machine to use for removing large amounts of wood and leveling the floor.

This is the sander you are most likely to purchase and least likely to rent. There are a number of models available now and they will all reach right into the apex of the corner. The best are lightweight yet powerful and are designed to sand into the smallest crevice. They also fit neatly into the hand.

Finally, the corner sander is for exactly that. The areas of the floor where two walls come together at a right angle. This is the only sander you are likely to buy rather than rent. The good news is you can get a very high quality sander that fits neatly into corners for $40 or less.

If you do gouge the wood go over it with the sander at a 45 angle to the gouge keeping the machine in motion at all times. When removing a gouge move the machine at a faster rate than you would during normal sanding. This will take some time as you will want to remove the gouge in small steps, remove the dust with a vacuum,

You should always sand the entire floor the same amount regardless of what imperfection you are trying to remove. Sanding is always about more than just preparing the floor for a new finish. It's also about getting the floor smooth and level again.

It has it's draw-backs. It will take a large amount of surface off in a very short time. For this reason it's a risky tool to use as it's very easy to gouge the floor and leave groves in the wood.

As you sand with this type of machine be sure to push it forward at a constant rate. Initially, sand a small area with it, use a shop-vacuum to remove the saw-dust, and then take a look at the effect. If too much is removed quicken your pace; too little slow down a bit.

As with the drum sander, expendables such as sandpaper, scouring pads, and the like are picked up at the time of rental and charged for upon the machine's return.


Regardless of sander type you'll want to start with a very course grit (20 or 36) sandpaper and work up to finer paper. Remember that the lower the number of the paper the courser the grit and the more wood will be removed. The higher the number the finer the grit and the less wood will be removed.

This is a sander specifically designed for resurfacing hardwood floors. It's large machine which typically takes a large sandpaper belt in a continuous loop. The machine is designed as a "walk-behind" tool. They can be rented at most major hardware chains at reasonable rates. The upside to using a sander like this is you "check-out" the sand-paper grades you want to use along with the machine and then pay for the belts you've actually used (and the time you've had the machine) when you return it. Most major chains will pro-rate the charges by the hour. Be sure to ask.

The edge sander is for areas that the drum or orbital won't reach. Chance are you'll want to use this sander regardless of which of the other two you do use. The professional edge sander will cover more area than a workshop sander and make the job faster and easier. This will not reach into corners very well though.

This sander is just an extra large version of an orbital sander. It's benefit is that it can help you level a floor without taking too much wood away. It will certainly remove varnish and shallow stains and burns. For stains and burns that run deeper the drum sander may be the better choice.

Neither the drum nor large orbital sander will allow you to get all the way up to the intersection of the wall and floor. This is what the edge sander is for. Like the orbital, technique is not as important, but you do want to sand in the direction of the grain and keep the sander moving if it's running.

With this type of tool technique is virtually everything. You should never have the machine running at a stand-still. Whenever this type of sander is running it should also be in motion. You should also sand in the direction of the grain of the wood.

The drum sander weighs about 110 pounds. If you are sanding on a second (or higher) floor or need to haul it up a step or two you may need a helper for assistance. The drum will sand a very large area before the sand-paper needs to be replaced. Also, changing the paper roll is relatively easy. You will also want to clean the machine completely before returning it. Most rental outlets will charge a cleaning fee if you return a dirty machine.

Start with 36 grit for normal wear and tear sanding or with 20 grit for deep stains and or burns. Once you've done the entire floor to the same depth move up to a higher grit ending with 80 or 100 just before staining. This may require you to make three to six passes with higher grits each or every other pass.

The amount of wood (due to burns/stains) and or surface wax/varnish/sealer you have to remove is the determining factor to a sanding machine. Unless your floor is relatively pristine you do not want to hand sand it, that will simply take too long.

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