OT - metal working vise
Bill Houghton, colder than Anchorage, CA No. Coast
>Another of the items from my father's garage (though originally from my revered Uncle Charlie's - when Charlie died, the vise migrated to Dad's garage, now to me) is a Prentiss vise, 108 pounds of serious metal worker's holding device. Fairly clean jaws, rotating base with what looks like a pull-to-release knob, nice vise.
I took it apart to load it into the car, trying to preserve my back, and, in unloading it, noticed that the rear jaw is a separate casting from the rest of the body. In the photo, you can see part of the line between them in the red section just behind the black rear jaw - that line continues at the black/red paint separation all the way to the base of the rear jaw. I googled "Prentiss vise" and lucked onto a machinist's forum discussion in which someone explained that these jaws swivel for holding tapered work if you remove the pin visible at the rear of that extra casting. I'll have to try it if and when I have a bench strong enough to hold it (right now, my only operational metal vise is a little round-slide Wilton bolted on a mechanic's rollaway).
So I guess back at the beginning of the last century, holding tapered work was a common issue, not just for patternmakers.