Before refinishing your hardwood floor you need to use wood dough to fill in holes and cracks. Wood dough is synthetic wood usually made of wood fibers used to fill holes, cracks and gaps. Once it hardens, it can be sanded like wood.
Step 1 - Purchase Wood Dough
Wood dough doesn't absorb stain the same way real wood does, so it might turn out a lighter or darker color than the wood after staining. Solve this problem by purchasing wood dough in a color that matches the wood you plan to use it on.
Step 2 - Check For Holes and Cracks
Check all areas of your hardwood floor to locate holes and cracks. Filling these areas with wood dough will make your floor smooth and flawless after finishing.
Step 3 - Apply
Use a putty knife to firmly press wood dough into holes and cracks in the wood. Spread the wood dough evenly with the putty knife making sure the wood dough is slightly higher than the wood. Allow to harden completely according to directions.
Step 4 - Sand
Use fine grain sandpaper to sand the areas where wood dough was applied. Sand until smooth and flush with the wood. Your hardwood floor is now ready to be refinished to look like new again.