vise jaws for parts with kerf?

[bink]

i drill and taps many parts that have been cut out on a high def plasma. if the plasma doesnt cut the sides pretty square, we have to hit them on a pedestal grinder to square them up. if we dont, the parts kick up in the vise and the holes end up at an angle. the sides dont have to be square, but i need the holes to be straight. does anyone make a vise jaw that would clamp on the kerf but still hold the part flat in the vise? i was thinking something similar to a toggle pad on a c-clamp??

[Geof]

I do not know of any source for what you describe but I solved a similar problem by making step jaws with an angled face on the step; I cut this with a dovetail cutter.

The parts were pushed down onto the step of the jaw by the wedging action as the angle contacted the top edge.