Forging; manual of practical instruction in hand forging of wrought iron, machine steel, and tool steel drop forging and heat treatment of steel, including annealing, hardening, and tempering

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1919 Excerpt: ...steel should also be experimented with to determine just how high a heat it will stand. When heavy forging is to be done, i.e., when the first rough shaping is done upon a tool, a comparatively high heat should be used. The steel should be forged at about what might be called a good yellow heat. The lighter hammering, when finishing, should be done at a lower heat, about the hardening heat, though very little, if any, hammering should be done below that point. If the grain of the steel has been raised by too high a heat, it can generally be quite decidedly reduced by a little hammering at some heat above the hardening temperature. Standard Forms Cold Chisels. The stock should be heated to a good yellow heat and forged into shape and finished as smoothly as possible. When properly forged, the end or cutting edge projects as shown at C in Fig. 123. It is a good plan to simply nick this end across at the point where the finished edge is to come, and then, after the chisel has been tempered, this nicked end may be broken off and the grain examined. Whenever possible, it is a good plan to leave on a tool an end of this sort that may be broken off after the tempering is done. When hardening, a chisel should be heated red hot about as far back from the cutting edge as the point A, Fig. 124. Care must be taken to heat slowly enough to keep the part being heated at a uniform temperature throughout. If the point becomes overheated, it should not be dipped in water to cool off, but should be allowed to cool in the air to below the hardening heat and then reheated more carefully. When properly heated, the end should be hardened by dipping in cold water to the point B. As soon as the end is cold, the chisel should be withdrawn from the water and the end polished bright ...