Does anyone know where I can buy silverline essex 8x20 sanpaper for a drum sander machine I intend to rent? The rental center charges $3.69 a sheet and I was hoping I could buy a pack of sandpaper online to save some $$$. Also, no matter how careful and diligent I am attaching the sandpaper it still leaves chatter marks, what kind of "adjustment" could the machine be out of to correct the chatter? Would finish sanding with a screen remove the chatter marks? I'm worried if I apply waterbased finish after screen sanding the miniscule residue from the metal screen will ruin the finish.

I don't use that sander so I can't help you out on finding paper. Just keep trying different search engines I suppose. Screening WILL NOT remove bad chatter. It MAY remove very light chatter. If you screen too much or too hard, you can dish out the floor. A hardplate buffer attachment is what us finishers use to sand out drum sanding flaws. Or you could try and buy what are called double sided disks. 3M makes them. They are sandpaper on both sides of a large paper disk used similar to a hardplate. Works good on most floors. Use 100 grit to sand out flaws followed by 100 grit screen. Screens DO NOT have any metal in them to rust. They are made from woven nylon mesh coated with silicon carbide, a mineral used in sanding. They will not cause the finish to rust. You need to clean the floors very well so there is no residue anyway.