Leg vise from junk

[Toolmaker51]

The heavy forged leg vises depend on a hinge at lower edge. Suddenly that causes wonder how they expect parallel clamping with that fixed point, though the jaw faces are far narrower then Tuomas's. There is no dispute his version works well on various thicknesses. And just like strap clamps for milling, the leverage is correct with tightening closer to jaws. Cannibalization of the screw jack, especially nut and thread is a super economical supply of sturdy material. Using all of it is perfection.
Unless you treasure rivets...