Leather Knife: the Harnessmaker's Knife, Forged from Cutlery Steel (Holford, 1907)

The harnessmaker's knife, the broad curved blade saddlers push through leather. Frederick Holford's 20th Century Toolsmith (1907) says it "will try the skill of the expert to its full extent". He cuts it from sheet cutlery steel of 0.75 % carbon, 3/32 inch thick, 4 to 6 inches wide; draws the cutting edge out at a deep cherry red; packs the steel with light blows at a dim red; anneals it in lime or ashes; hardens it from a low cherry red in the bath; and draws the temper to dark blue, the temper he gives for all leather-cutting tools. He gives no handle wood and no outline sizes beyond the width; those are unknown here. Source: F. J. Holford, The 20th Century Toolsmith and Steelworker (1907), pp. 163-166 and p. 21 (the hardening bath). Picture: his Fig. 94.