Abstract: An arcuate debarking tool for ring rotor debarking machines used in timber processing. The tool comprises an elongated, arcuate body having an outer end that removably mounts a cutting element, and an inner arbored end adapted to be coupled through a mandrel shaft or the like to a ring rotor. A curved, thread-like leading edge first contacts logs that are transmitted axially through the revolving apparatus, and deflects the tools radially outwardly until the log is surrounded by the revolving ring of debarking tools. A companion, spaced apart exit edge is angularly defined in the frame. It functions in a thread-like manner to slowly unengage the rotating tools from the longitudinally traveling, debarked log. The curved exiting edge threadably revolves about the log circumference and slowly transfers the only remaining contact point between the withdrawing log and the revolving tool to an inward position whereby the tool is slowly, rather than suddenly, allowed to radially retract.