Abstract: A swing saw for cutting logs to length prior to cutting into lumber or plywood veneer is provided with a rotary arbor shaft coupled to a secondary drive shaft through a drive chain, the secondary drive shaft being coupled to an electric drive motor through drive belts. The secondary drive shaft is supported on laterally spaced bearings which, in turn, are maintained parallel by adjustment screws mounting rotatable sprockets which are coupled together through a secondary chain by which adjustable rotation of one of the sprockets effects simultaneous adjustable rotation of the other sprocket to precisely the same degree and direction. The adjustment screws thus are moved longitudinally in the same direction and precisely the same distance, and therefore the axis of the secondary drive shaft is maintained precisely parallel to the axis of the arbor shaft. The secondary drive shaft is secured by clamp plates when adjusted. Both shafts are mounted on a hollow housing in which the drive chain is contained.