Long jaws....

PV:

Of course you can, we did it all the time, even with three vises. Two vises is a snap, you just need a couple of spider handles and spin them simultaneously.

Oh.... *simultaneously*, eh??

Bingo.

I have also used 1/2 13 shoulder bolts, through hole in the moveable jaws, that you only snug when clamped.

Also done with a 24" radius cut into the step in the jaws so the outside clamps first; you cut them clamped *hard* on a couple 123 blocks, with Kanttwists on the outside.

You havent lived till you have done all this on a hand change 4 axis Kasuga with a Centroid controller.

Couple of holes in the sheetrock, but hey, job done.

PV:

Yeah, but that's only after you first screw the jaw on and have to crank it up to your part (or your 1-2-3 blocks so you can machine the jaws). After that it's no biggie since you're only loosening it just enough to remove and insert the next part.