Quick-Acting Hardwood Bench Vise with Cam and Drop Roll (Boy Mechanic, 1919)

"A detail is given of each part, with dimensions, so that it is not difficult to make it from hard wood."

Cut every part from hard wood to the sizes in the drawing: the 6-1/2 x 7-3/8 x 3/4 in plate with its 2-5/16 x 2-7/16 in opening, the 6-1/2 x 4 x 1 in slotted plate, the 5 x 5-1/2 x 1/2 in plate, the blocks, the forked piece, the long bar drawn at the bottom (2 x 1-3/8 in; we take it to be arm C) and the cam lever (5-1/2 in between centres, 5/16 in pin hole; its edge view is drawn 5/8 in).

Make roll A, a round hardwood roll 1-1/16 in across and 1-7/8 in long.

Fit the parts under the bench top as the section view shows: arm C slides through the fixed part, roll A sits in its curved seat behind the jaw so it can drop and wedge the arm, jaw B is pivoted so it swings loose, and the cam lever is pinned at the front. Screw and bolt the fixed parts to the bench.

To open: turn the cam, then lift the front of the vise to free roll A, and slide the front jaw out to the size of the work. Put the work in: roll A drops into place and clamps arm C. Turn the cam to tighten.

From **The Boy Mechanic, Book 3** (Popular Mechanics, 1919), p. 85, by J. C. Hansen (checked on the archive.org scan boymechanic0003unse). The text names only roll A, jaw B, arm C and the cam; build the other pieces as drawn. Metric figures are ours.