Belt sanding a floor requires careful technique and the right tools. While large floor sanders are typically preferred for whole-floor jobs, a handheld belt sander can be effective for smaller areas or repairs. The key is to work with the grain of the wood to avoid damaging the surface.
Preparing for Belt Sanding
Before you begin, ensure you have the necessary safety equipment: safety glasses, a dust mask, and hearing protection. You'll also need various grits of sandpaper for the belt sander, starting with coarser grits to remove old finish and gradually moving to finer grits for a smooth finish.
The Belt Sanding Process
-
Start with a Coarse Grit: Begin with a coarse-grit sandpaper (e.g., 36-grit or 40-grit) to remove any old finish or significant imperfections.
-
Maintain Parallel Movement: Always keep the belt sander moving parallel to the wood grain. Moving across the grain can create deep grooves and damage the floor. A video demonstrating this technique can be found here: Refinish Your Hardwood Floors Using a Belt Sander. As noted in the video, avoid back-and-forth motion, which can create uneven sanding.
-
Gradual Grit Progression: After the coarse sanding, switch to progressively finer grits (e.g., 60-grit, 80-grit, 100-grit, and so on) to achieve a smooth surface. Each grit removes the scratches left by the previous grit.
-
Overlap Strokes: Slightly overlap each sanding stroke to ensure even coverage and avoid leaving un-sanded areas.
-
Light Pressure: Apply gentle, even pressure to avoid gouging the wood. Let the sander do the work.
-
Regular Checks: Frequently check your progress to avoid over-sanding.
-
Edge Considerations: Be especially careful when sanding near the edges of the floor to avoid creating unevenness. A handheld belt sander is less suited for large-scale flooring.
Alternative Tools and Considerations
While handheld belt sanders can be used, professionals often utilize larger drum or belt sanders for efficiency and evenness on entire floors. As noted on Reddit (So many "Don't DIY your floors" comments...), professional floor sanding companies rarely use handheld belt sanders. For small repairs, an orbital sander might be a safer option, as mentioned in this Stack Exchange post: Should I use an orbital sander or a belt sander for sanding a section of varnish.
Remember to always follow safety precautions and work in a well-ventilated area.
