GB815037A - Method of forming spiral cutter blades - Google Patents

Abstract

815,037. Making spiral cutter blades for planers and milling cutters; bending; twisting. KEARNEY & TRECKER CORPORATION. May 6, 1957 [May 18, 1956], No. 14325/57. Classes 83 (2), 83 (3) and 83 (4). A spiral cutter blade is made by heating a blank whilst located between a pair of spiralforming dies, and then closing the dies to impart the desired spiral contour to the blank. A cutter blade 18, Fig. 1, for use in cutting tools such as reamers, end mills or shell mills, is made by heating a carbide blank 25, Fig. 5, to a plastic condition between dies 27, 28, and then pressing it to form a cambered blank, Fig. 3 (not shown), heating the cambered blank to a plastic condition between a further set of dies 39, 40, Fig. 7, and then pressing it to form the spiral twist in the blade. The blank 25 is of sintered carbide and is heated in the dies 27, 28 to 2600‹ F. by a high-frequency coil, and in the dies 39, 40 by another high-frequency coil 47. Both sets of dies are made of copper to permit rapid conduction of heat from the blank and hence to reduce the time during which the blank is at a high temperature and subject to oxidation. The pressed blades 18 are located on seats 20 in a cutter body 17 and are brazed thereto.