Democratic Sentinel, Volume 20, Number 10, Rensselaer, Jasper County, 13 March 1896 — Tempering Saws. [ARTICLE]

Tempering Saws.

Tempering saws is an elaborate process, and none but the best, workmen are employed. Instead of being hardened by* dipping the red-hot saw in water, a composition of whale or some other animal oil and tallow is used. Sometimes rosin, pitch or turpentine is mixed with tlie tallow and oil. The oil and tallow give the steel strength and toughness, ami the rosin, pitch or turpentine break tip the settle made liv the heat, orns it is culled, makes “the scale strike." The saw is carefully heated iu a furnace, which gives every part of the thin metul an even heat. Then the blade is dipped in the hardening mixture, and kept there until it is as coo! as the composition. When tuken from the oil and tallow mixture the oil is removed by scraping, and the blade i* further cleaned with sawdust. When the steel is bright, tlie temper is drawn. This is done in several ways; lly laying it iu a muffle until the proper color comes, by reheating the blade in a frame which stretches It so that the blade will not warp, and by healing it between dies which hold the blade flat.