In 1949 Henry Persson filed a patent for a drill press vise that held a workpiece flat against the drill press table and did not require permanent modifications, such as drilling holes, to the machine. By December of 1950 Persson's "Float-Lock Vise" was being offered for sale by Float-Lock Corp., of Bloomfield, NJ. The patent was granted in 1951.
In October 1951 American Machine & Foundry Co. (AMF) purchased Float-Lock Corp. AMF already owned drill press chuck maker Wahlstrom Tool Co., and they would market Persson's invention as the Wahlstrom Float-Lock vise.
In 1953 AMF announced a redesign of the vise to make it faster, stronger, and greater in capacity with 9 inch and 12 inch jaw openings. They added a slight angle to the table locking clamp to add some downward force to hold the vise on the table. This new design is immediately visible in the thicker ratcheted jaw face plate.
Over the next couple of decades the Float-Lock vise proved to be a steady seller for AMF, even as AMF's overall financial health deteriorated. A web page detailing the history of the AMF logo can be useful in estimating the date of manufacture of your AMF Float-Lock vise.
In about 1968 AMF sold the Wahlstrom and Float-Lock product lines to R. J. Okon Co. of Linden, NJ, which operated them as the Wahlstrom Float-Lock Products Co., and relocating them from Bloomfield, NJ to Linden, NJ.
In about 1981 Wahlstrom Float-Lock Co. was sold to Allen J. Bassel Sr., who also owned Burgess Mfg. Co. of Libertyville, IL. The Wahlstrom Float-Lock business was relocated Libertyville where it shared premised with the Burgess company.
In 1999 Eagle Rock Technologies, Inc., of Bath, PA, purchased the Wahlstrom Float-Lock Products Co., and continued manufacture of the Float-Lock vise until 2018 when that product line was discontinued. Those looking for such a vise might look at the similar Grip-Master Safety Drill Vise from Heinrich Co.
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