I recently pulled out some carpet in a small room of my house, with the plan of refinishing the hardwood floor underneath. The floor is in pretty good shape with the exception of some wear near the door, but nothing big. So I though, since the room was small and I just needed to get the old finish off, I though I would try to do it with a small belt sander. It would take longer but reduce the risk of me damaging the floor with a big machine. It was actually going quite well but then the belt started getting clogged up constantly, with big chunks of hard junk that completely covered the grit, making it impossible to make progress. Also whatever was clogging it was mostly impossible to get off the belt. After messing with it for a while, I decided that whatever the floor was last finished with must be the culprit. I was about to go rent the floor sander from the hardware store, but then I though that since that machine is essentialy a large belt sander, what if it does the same thing? Then I've wasted the rental money and ruined a more expensive belt.
My question is then, how should I proceed? What could be on the floor and how can I get it off? Could I used the drum sander or do you think it will clog up as well?