The boring bar, which is shown in the accompanying engraving, is particularly adapted for use in boring out car wheels to fit the latter to the axle instead o the axle to the wheels. The device is of very simple construction and provides means whereby the tool-holding blocks may be quickly and accurately adjusted, as the work proceeds. The boring bar is indicated at A in the engraving, which shows only the lower part of the tool. In this bar is a transverse slot adapted to receive a pair of blocks, ? and C. A screw, 7), passes through these blocks. That portion of the screw which jjasses through block ? is cut with a right-hand thread, while the portion engaging block (1 is formed with a left-hand thread. To prevent longitudinal movement of the adjusting screw 7) it is retained by means of a pair of rods, E. which ]iass through the bar A and fit into an annular channel in the center of the screw 7). The block ? is formed with a transverse slot to receive the cutting tool, F, and similarly, the block C carries the cutting tool, G. The iJins 77. in the blocks ? and C prevent the cutting tools from being moved too far inward. The cutting tools are clamped in the required position by means of screws, K. A slit extends from the end of the bar A to the transverse slot in which the blocks ? are held, and by means of a screw L the opposite sides of the bar A may be drawn together to clamp the blocks in set position. Whenever it is desired to adjust the cutting tools it is merely necessary to release the screw L and then by turning the screw ?) the blocks ? and C may be adjusted toward or from each other, carrying their respective cutting tools F and G inward or outward to the required degree. The ends of the blocks ? and C are beveled and rounded so that when the screw L is tightened the blocks will be clamped at the ends as well as at the sides. A patent on this boring bar has been secured by Mr. William Chase, .Tr., lndianapolis, Ind.