A log debarker for debarking a lengthwise-moving log includes a pair of debarking subassemblies each including a pair of cylindrically concave, rotating cutter elements juxtaposed on opposite sides of the log and formed to debark a quadrant of a log. Each debarking subassembly includes a stationary support frame, a tilting head platform and a pivoting cutter assembly supporting the cutter elements linked to the support frame so as to pivot the cutter element about an axis normal to the log axis as the cutter assembly is tilted. The cutter elements are moved toward or away fron one another to adapt to different log diameters and are pivoted about an axis normal to their axes of rotation. Pivoting the cutter element skews the rotational axis of the concave cutting surface to an oval of a reduced effective radius of concavity in a plane normal to the log axis to debark a smaller diameter log. The cutter elements are pivoted in opposite directions so as to nest within one another and are counterrotated to negate turning of the log during debarking.
