Most bench vises grip work through a threaded spindle that you crank by hand, and that is the usual benchmark here. Workshop From Scratch went a different route: an orange bench vise was modified so a hydraulic cylinder actuates the jaws, fed by a pump driven by compressed air. The maker says the result is very strong and makes work much faster and more comfortable, and a foot pedal marked RELEASE suggests clamping can be done without touching the handle at all.
The construction reads as a proper fabrication job rather than a bolt-on accessory. A thick metal base plate forms the foundation, with a large central hole cut by a hole saw and the edges smoothed on a belt sander. The outer sleeve is a U-shaped channel welded up from three long plates, and the inner sliding component is a square metal tube cut to length. Inside that assembly sits a 5 ton pull-back ram, with a heavy-duty spring and a nut securing its threaded piston rod. Triangular gussets reinforce the ram's fixed mounting point, textured metal plates bolt on as jaw faces, and a front cover plate shields the sliding jaw's internals.
The process details are tidy: magnetic squares held plates at right angles during tack welding, holes were punched and drilled on a drill press, and the finished parts were spray-painted bright orange. Testing involved clamping and crushing a flat plate, a round pipe and a square tube, all of which deformed under the grip.
One thing left open: the maker has not said whether the whole design is their own original idea.
Project by Workshop From Scratch. Watch it on their YouTube channel: