Later I replaced that clamp with this one so that the contact surfaces were only made with
smoother and more accurate pieces of three quarter and one inch cold rolled key stock.
The drawings on the next two pages show the current
clamp mechanism. By properly adjusting the top and
bottom 3/4" clamp bolts (putting a little more pressure on
the bottom clamp bolt than on the top) and adding a little
pressure with the jack, the vertical slide can be raised in
increments of .0001" (by light taps!) and the table does not
move when the clamp bolts are tightened!