Tumble finishing, also known as tumbling or rumbling, is a technique for smoothing and polishing a rough surface on relatively small parts.
Tumbling is used to burnish, deburr, clean, radius, de-flash, descale, remove rust, polish, brighten, surface harden, prepare parts for further finishing, and break off die cast runners. Tumbling is an economical finishing process because large batches of parts can be run with little or no supervision by the operator. A full cycle can take anywhere from 6 to 24 hours with the barrel turning at 20 to 38 RPM.