how is a zero edge heat treated?

[hardheart]

I had read that the edge of a blade needed to be about 1/64th thick for heat treating, and the edge bevel had to wait til after that step. How is damage to the thin steel at the edge prevented?

 

[mete]

Damage ? Are you refering to decarburization ? Painting the steel with a decarb preventer or heat treating in metal foil will do it.