Hold fast

A hold fast is an accessory used on a woodworking workbench and in blacksmithing to fix a workpiece to the top or side of the bench while it is being worked.

A hold fast is shaped like a shepherd's hook. In use, the shank fits loosely into a hole in the top or side of the bench and the tip of the hook is pressed against the work. The hold fast is set by rapping the top with a mallet, which causes the shaft to wedge against the sides of the hole. It is released by hitting the back side.

While "artisan" hold fasts continue to be made as steel castings, or forgings, modern hold fasts are made from round mild steel bar stock using highly automated cold-working machines. Gramercy Tools markets such hold fasts, made from cold-rolled bar stock which is slightly under 3/4" (19.05mm) dia., usually 23/32" (18.25mm), for use in the now customary 3/4" dia. bench hold fast holes. The making of such a hold fast is more particularly described in the patent document (U.S. Patent 7,571,631, to Moskowitz, et. al.).

A holdfast (note different spelling) is a plinth or pedestal, usually of reinforced concrete, to which an anti-aircraft or coastal battery gun was fitted. Holdfasts are often the only evidence for a weapon that survives.

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