Dating spear jackson saws

The term set describes how much the teeth protrude.The kerf may be sometimes be wider than the set, depending on wobble and other factors.Please see our terms if using more than a few dates or photos.

A large measure of hand finishing remains to this day for quality saws by the very few specialist makers reproducing the 19th century designs. In parts of early colonial North America, it was one of the principal tools used in shipyards and other industries where water-powered sawmills were not available.The use of steel added the need to harden and temper the saw plate, to grind it flat, to smith it by hand hammering and ensure the springiness and resistance to bending deformity, and finally to polish it .Most hand saws are today entirely made without human intervention, with the steel plate supplied ready rolled to thickness and tensioned before being cut to shape by laser.Most blades were made of steel (iron carbonised and re-forged by different methods).In the mid 18th century a superior form of completely melted steel ("crucible cast") began to be made in Sheffield, England, and this rapidly became the preferred material, due to its hardness, ductility, springiness and ability to take a fine polish.

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