After reading several articles with their own subjective evaluation of ROSs, I decided to apply a simple numeric test to compare two of them and I was surprised by what I found. I hope you find this interesting and useful to decide your next ROS purchase.
The fairly straightforward logic goes like this:
- Unlike disk sanders, each grit particle on an ROS moves in a more or less circular orbit, and ALL of them move in the same orbit (as long as the pad is not spinning wildly)
- Call the orbit diameter "D" and the OPM (orbits per minute) "R". Simple math tells you that each particle travels a distance of pi*D inches per orbit, and pi*D*R inches per minute, or pi*D*R/12 feet per minute.
- To compare, say, the Ridgid R2610 with the PC 97366 and with a belt sander, consider this:
- the R2610 has R=1/4 and R (max) = 10000 in aggressive mode. This gives the particles a speed of 655 feet/min
- The PC97366 has R=3/16 and R(max) of 6000, giving it just 295 feet/min.
Incidentally, the amperage on both is about the same too. Startled? I sure was.
-Ram