Toolbox: Putting Random-Orbit Sanders to the Test

I've had the opportunity to extensively test three random-orbit circular sanders — a Bosch model 3283DVS, a Porter-Cable model 7334, and a Marshco sanding head on a 4-inch angle grinder. After using all three sanders in my stairbuilding business for a period of several months, I find that each one can cut the time I spend finishsanding by at least 30 percent. Sanding across grain is possible without leaving sander marks, so nosing returns are no longer a problem. And the resulting finish is noticeably smoother than with a palm sander. I didn't get swirl marks on oak with 120-grit or finer paper, and with 80-grit paper, the marks were very slight. Different Strokes Each of the sanders I reviewed differs in