Random Orbital Sander

Overview

A random-orbital sander finishes wood, filler and paint without leaving the swirl marks a fixed-orbit sander makes. A round abrasive disc is held on a Sanding Pad Assembly by a hook-and-loop face; the platen is driven both around a small orbit and, independently, in free rotation, so no point on the disc ever repeats the same path. The whole tool sits under a one-handed Palm Grip Cap inside the nylon Housing Assembly, runs off a slide-on Battery Pack, and pulls its own dust through an integral Dust Extraction System system.

How it works

The Brushless Motor is a compact brushless unit. Its shaft does two jobs at once: it spins the Dust Impeller that drives extraction airflow, and it turns the Eccentric Drive Head head that creates the sanding action.

The randomness comes from the head's geometry. The pad mounts on a bearing whose seat is offset from the motor axis on the Eccentric Spindle, so the platen is swung around a 2.4 mm orbit. Because that pad bearing is free-floating, the disc is also free to rotate at its own rate, and the combination of orbit plus free spin gives the non-repeating pattern. A Counterweight cancels the offset mass so the tool does not buzz, and a Pad Brake Ring caps free-spin RPM in the air so the disc does not gouge when it first touches the work.

Dust drawn through the pad holes is collected in the Dust Canister, while the Speed Control Board holds the set orbit speed steady from the Trigger Switch dial as load changes.