A broach is a multi-tooth cutting tool that finishes a surface in a single linear stroke. Along its length, the broach carries a progressive series of cutting teeth, each standing slightly taller or wider than the one before it, so tooth after tooth removes a thin, predictable chip from the workpiece. Because roughing, semi-finishing and finishing edges are all built into one tool, broaches hold tight tolerances and deliver a smooth surface finish at cycle times that drilling, milling or reaming cannot match. That is why broaches and broaching tools are everywhere in high-volume production: keyways in gears, splines in transmission shafts, round holes in hubs and hexagon sockets in fasteners.<\/p>