Smoothing out the hole story
For years I’ve used a Bosch 5" random-orbit sander, and recently added a 6" Bosch to my shop. But while buying hook-and-loop sanding discs for the new tool, I noticed it has a six-hole pattern, compared to the eight-hole pattern on the smaller sander. Doesn’t it stand to reason that a larger sander—which removes more material—would need more holes to suck up the dust?
—Jeff Crowley, Davis, Calif.
Good catch, Jeff. According to Jim Stevens, Bosch’s longtime product manager for woodworking power tools, Bosch sanders decades ago used pressure-sensitive-adhesive (PSA) discs with five holes for 5" models and six holes for 6". In 1989, Bosch—and, later, other manufacturers—began using hook-and-loop pads and abrasives with an eight-hole pattern for 5" sanders to make disc changes easier and improve dust-collection efficiency.
But Bosch’s 6" sanders never changed from the six-hole pattern, even when switching to hook-and-loop pads, because, Jim says, the larger motor and blower collect dust well enough to not warrant an upgrade.