Abstract: Orbit saw apparatus including a driven shaft rotatably supported in an upright mounting wall which is part of the frame in the apparatus. Orbit arm structure is rotatably supported on one end of said driven shaft, and an arbor shaft parallel to the driven shaft and mounting a circular saw blade is journalled on the orbit arm structure. A motor has its output shaft connected through belts to the driven shaft, and the driven shaft is connected for drive purposes to the arbor shaft. The motor also runs a pump, which is part of a pressure fluid supply system for an adjustable hydraulic motor which produces rotation of the orbit arm structure.