Technical Notes - Blade Metallurgy
A2 plane blades
The tool steel A2 has definitely become popular for woodworking blades since I made the first one back in 1995, and a number of manufacturers have followed me in the use of this alloy. It now seems to be the main material used for plane blades.
The analysis for this A2 alloy is very varied as are the specifications for the heat treatment. Without going into great detail I will say that the blades go through several complex stages of heating at different temperatures. Then the blades are triple tempered, followed by a soak for considerable duration in liquid nitrogen. Unless these stages are completed properly, with precision in the right sequence the material will not realise it’s true potential. It is also important to start off with the right analysis for the material.
It is this attention to detail which has given my blades their unsurpassed reputation.
S 53 Blades
These blades are made from powder metallurgical steel, which has basically the same characteristics as the A2. Tests have shown that the edge will last several times longer than the A2 blades, saving even more down time.
The blades are treated in a vacuum furnace to a high temperature to achieve a hardness of HRC64, they are also triple tempered and cryogenically treated.