I am restoring a 2000 square foot wood floor. I just rented a drum sander from a rental shop and tried it. It was not enough! This floor is 3/4 inch solid, and has never been sanded. It does have some uneven peices and it has some old "tar" paper that was on top of it and under some underlayment I removed, but it is still dark in those spots. The drum machine I used just didn't do the job. I have heard that you have to be worried about gouging, well I couldn't gouge this old floor, unless I really tried. Does anyone know if there is a real heavy duty sander that I could rent?