Tool Review: Random-Orbit Sanders

 

Like doing income taxes or having a root canal, most of us don't cherish the experience of sanding our woodworking projects. That's why we love random-orbit sanders: They create smooth, finished surfaces quicker than any sander or method.

Here's how they work: As the sanding pad spins (from 7,000 to 12,000 rpm on most variable-speed models), a cam adds an eccentric orbiting motion (between 1/16" and 1/8" off-center) that effectively blends the scratch marks of the abrasive uniformly across your workpiece. Sand with two or three progressively finer-grit discs, and you've got a project ready for finishing. Some models get the job done fast, while others take their time. And only a few combine a superb finish with speed, comfort, and ease of use. Here's what we found in testing palm-style random-orbit sanders.

1. Smooth, scratch-free finish. If your random-orbit sander doesn't produce a smooth, level surface without scratch marks, it's hardly worth owning. We divided red oak and pine boards into three equal sections, drew pencil marks on all three sections, and sanded with a new 80-grit disc until the marks disappeared. Next, we marked only two sections, and sanded those with 150 grit. Then, we marked the last section only, and used 220 grit. Finally, we stained each board, and evaluated the quality of the finish. After 150 grit, all of the sanded boards showed scratches that collected pigment from the dark-walnut stain. With seven models, those scratches virtually disappeared after 220 grit in both species. (We considered an occasional tiny mark acceptable.)

2. Aggressiveness. Like you, we want to get the sanding done as soon as possible. To evaluate aggressiveness, we sanded oak plywood with new 120-grit discs at top speed, applying only the weight of our tester's hand, and recorded how long it took to sand through the veneer, looking for models that removed the veneer quickest. The most aggressive sanders cut through the veneer nearly three times as fast as the slowest model.

3. Dust collection. All tested sanders sport on-tool dust collection, but not all performed equally. We checked each unit's effectiveness by sanding equal amounts off oak and pine boards placed on a black surface. Most sanders, when using their attached collectors, left little evidence on the table. Most also gobbled up all the dust when attached to a shop vacuum.

4. Vibration, control, comfort. A jittery sander leaves you with tingling hands and gives you one more reason to dread using it. And some sanders want to "run" out of control at the slightest shift of your hand. Fortunately, three sanders earned high marks in all three areas of user comfort.

Top Tool: Porter-Cable 390K
Top Value: Milwaukee 6021-21

Learn the complete results of our testing of the Bosch ROS20VK, Craftsman 25927 and 27673, DeWalt D26453, Festool ETS125, Hitachi SV13YA, Klingspor KA1893DVS, Makita BO5012K, Milwaukee 6021-21, Porter-Cable 343VSK and 390K, and Ridgid R2600 in the October 2008 issue of WOOD magazine, or download the review.

Download the review