To set the height of a control box in a frame swinging type horizontal band saw machine while it effects cutting or receives a large material to be cut.

A base block 1 is fixedly provided on its front in the left with a guide member 10, to which a vertically slidable control box 11 is attached. The control box 11 is formed in its left-hand side with a slot, through which a fixing knobbed bolt 12 is inserted for screw fitting into a tapped hole made in the guide member 10. The fixing knobbed bolt 12 is used to fix the control box 11 to the guide member 10 at a height from H1 to H2.