Heat treatment is a critical step in the tool making process. We harden and temper our blades to give them the right blend or hardness and toughness. T0 harden the blades, we heat them up to 820 degree C, till the steel is glowing "Cherry Red" then quickly transfer them to a quenching bath, where the temperature is rapidly bought down to 20 degrees. This aggressive treatment captures the steel in a unique crystaline structure making it very hard, but brittle. To give the blades the necessary toughness we then temper them back in another furnace at 360 degrees for 2 hours. This slow gentle process, releases the stress and allows the formation of more granular of the steel structure. This also gives the steel its blue / grey appearance.
AuthorJames is a young toolmaker from Warrandyte. Follow James on his journey to design and make quality garden tools and artwork. Archives
February 2016
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