Machinist Vise and Milling/Drilling Vise Stops

[Toolmaker51]

In my book the best vise stops do not attach onto jaw itself...but into body of the non-moving side, just as jjr2001 describes.
I'll offer an easy work-around of slotting this variety of clamp.

a] Lightly sand or surface grind two plates of desired clamp size, a good proportion is width 3-5 times the rod diameter, with the pair twice rod diameter in thickness.
b] Drill and tap one side, clearance drill the other, this will provide clamping action via a screw. 1/4-20 or 28 is satisfactory.
c] Clamp both face to face in machine vise, with 2 thicknesses of paper in between.
e] Edge find for the middle, distance from end and spacing hole to hole. I like offsetting holes from center to make re-orientation easy.
f] Center, pilot, and drill [or ream] to size.
Bingo!