Proper sanding levels the floor and brings back the grain, one of the desirable attributes of a hardwood floor. Several passes with the sanding tools will be required to achieve a smooth finish. Provide ventilation while sanding and staining. An open window with a fan is a good idea, especially since the door is sealed.
The drum sander is the first tool you'll use. It's not a part of most homeowners' tool collections, but is readily available as a rental tool. If you've never used a drum sander, you may be in for some surprises. It's large and rather noisy. It's also very efficient. Drum sanders remove a lot of material very quickly. One of the most common mishaps of do-it-yourself floor refinishing is gouging the wood with the sander. A few seconds is all it takes to do the damage. Here are a few tips for using a drum sander:
- Start the sander while the machine is tilted back and not in contact with the floor. After it's up to full revolutions, slowly lower it to the floor surface.
- Start or "practice" in an area that you know will be covered by a large piece of furniture, such as a sofa or bed. That way any beginner sanding errors will be concealed. Even better - practice on a sheet of wood or plywood until you get the feel for the machine.
- Keep it moving - it's not hard to move forward or backward, just don't let it stand still while running.
- Work slowly and let the machine do the work.
You are removing dirt and old stain and creating a new level surface, so choose the initial sandpaper accordingly. Remember the smaller the grit number, the rougher the sandpaper and the more material it will remove. Start with a coarse grit and move to finer grits as the floor begins to get smoother with each sanding.
Sanding grit estimates vary according to the condition of your floor. In general, begin with a 20 to 60 grit and end with 120. You may choose to skip the 20 grit pass if the floor is relatively smooth. Always use the same grit progression on all areas, whether drum, edge or hand sanding.
Remember to clean the floor thoroughly after each sanding grit change.