A sawmill comprising first and second clamp members for clampingly engaging opposite sides of a log or log cant. A trolley includes the second clamp member. For moving the trolley cross-wise of the sawmill base, a threaded rotatable rod, to which a handle is attached, extends cross-wise of the base. The trolley includes a pair of walls which have a pair of aligned vertically oblong apertures respectively for receiving the rod. A half nut is fixedly attached to a bottom of one of the apertures and has threads which mate with threads on the rod so that the rod can threadedly engage the half nut. The apertures are sized such that the trolley can be tilted so that the threads of the rod and the half nut can be disengaged and the trolley slid along the rod to an approximate position for clampingly engaging the second clamp member to the log or log cant, then, with the trolley positioned upright and the threads of the rod and the half nut re-engaged, the handle can be turned to apply clamping force by the second clamp member to the log or log cant.