Final Drum Passes with Burnished 80 Grit or Regular 100 or 120
After 36 and 60 the next-grit of sandpaper will be 80-grit, and then the last pass with the large drum machine will be done with burnished 80-grit. Or you can use 100 or 120, but I prefer to burnish the 80-grit on the drum. The-grits in this 80-grit paper can be dulled creating a 100-120 buffing paper, by simply touching a piece of fine paper to the spinning drum. Again, be sure to use a piece of fine sandpaper and touch it lightly but evenly across the whole drum as it is turning. This saves you from having to buy a roll of this very fine sandpaper, and in my opinion will do a better job of polishing the wood. Most sandpaper makers cringe when they hear this, I wonder why. Now if you have done a good job of tuning up your floor sander, you will see almost no chatter marks in the floor. But if you do, don’t worry too much we will address them later in this article.
On the last two sandings with the finest-grit paper you will want to ease off the drum tension just a bit each time. During fine sanding you also have to take care with this tension. You may find that too light a drum tension will start to make the drum skip across the floor or create chatter marks. In this case try increasing the tension. And slow down your pace of sanding across the floor.