After using the drum sander, next step is to smooth out the wood with a vibrating sander.
Roughly the same size as the drum sander and also employing a dust bag, the vibrating sander will come as a welcome relief from the drum sander. It's lighter, there's less danger of hurting the wood, and because of the vibrating motion it's easier to move across the floor.
Another option is to use a large orbital sander also available at the tool rental yard.
Either the vibrating or the orbital sander will take your hardwood down to its smoothest finish.
Next...Edge Sander

