Originally Posted by
Wiley Horne
On the subject of Ouchii, it is difficult to find actual metallurgical studies which have tried to get to the bottom of what makes a great chisel. One such study was conducted by a fellow named Bill Stankus, and the Ouchii chisel came out on top of the 11 Japanese and western brands tested.
The reference is "Testing Wood Chisels", pp. 80-84 of a softbound book, 'Bench Tools', from the series The Best of Fine Woodworking. Taunton Press, 1990.
Stankus bench-tested 11 chisels, rating them for edge retention, then cut the chisels up into pieces for metallurgical analysis, testing each one for carbon content, Rockwell hardness at the cutting edge, grain size, carbide presence and distribution.
Stankus then sought to relate the performance of each chisel to these metallurgical properties. What emerged was that hardness alone (Rc hardness) did not explain edge retention or chipping--fineness of grain, and carbide presence and distribution, were essential to edge holding. The three Japanese chisels had the best edge retention, and it appeared to be based jointly on fine grain, good carbide presence and distribution, and Rc hardness. It is notable that only one of the 3 Japanese chisels had an Rc value above 61.5, and that was the most expensive one, an Ouchii at 63.5.
You may be familiar with that study, but I mention it in case not.
Wiley