Abstract: A chop saw for selectively cutting logs to various lengths includes a motor-driven circular saw blade mounted at the outer end of a saw carriage pivoted to a fixed base. A rotary crank mechanism driven by a hydraulic motor on the carriage oscillates the carriage about its pivot to feed the saw blade into and out of a log held in cutting position alongside the carriage by hydraulic cylinder-operated clamp arms which are also mounted on the fixed base. A crankshaft of the rotary crank mechanism carries a cam which operates a hydraulic flow control valve in the hydraulic circuit of the carriage drive motor to reduce the speed of the motor and thus carriage travel only when the saw blade cuts through the log. Limit switches in an electrical control circuit and operated by cams on the crankshaft control the operation of valves in hydraulic circuits for the clamp cylinders and carriage drive motor to coordinate the positions of the carriage with the closing and opening of the clamp arms.