Abstract: The guide head is used in pairs secured above and below the work table of a band saw machine, to twist the blade up to 90.degree. enabling the machine to cut off a length of a work piece exceeding the throat dimension of the machine. Each guide head comprises a casing having a plug swivelable up to 90.degree. within it. Each swivelable plug has a vertical opening through which a saw blade can be trained. Each plug has upper and lower pairs of side guide rollers rotatably journaled on spaced, parallel, removeable pintles. Each roller has large- and small-diameter cylindrical end portions. The large-diameter portions are spaced apart to engage opposite sides of a band saw blade trained through the swivelable plug.