Open Coat Versus Closed Coat Impacts
Open vs Closed Coat: Silicon Carbide Sandpaper Guide Saturday morning in the shop is supposed to be simple: one mug of coffee, a walnut desktop to final-sand, and a couple of hours of quiet before the house wakes up. Instead, at pass number fifteen, the paper glazes over. The dust lines smear into the grain, and the sander’s pitch changes—a small but telling protest. I switch sheets, still chasing that consistent, haze-free scratch pattern. When I move to wet-sand a lacquer test panel, silicon carbide sandpaper comes out of the drawer—its black grit and smooth backing a distinct contrast to the tan aluminum oxide I’ve used on the walnut. Ten minutes later, I’m flattening a glued-up end-grain cutting board, then stepping over to clean up a steel plane body. Same sander, same operator, but suddenly my results diverge depending on one detail I often overlook: how densely the abrasive grains were packed onto the paper in the first place.