On Mar 13, 9:35*pm, "Terry Coombs" wrote:
Michael Koblic wrote:
...
Mine tilts back about 0.008" in 3". I have done nothing about it for
fear that I will make things worse.

You could remove the column and measure the connecting surfaces to see
which one is off. An indicator mounted in the chuck ought to read a
constant value against the column while you extend the quill.

To measure squareness of the base attachment surface, attach a fixed
horizontal rod near the lower 1x2 edge of a 1-2-3 block and an
indicator near the upper edge, parallel with the rod. The block needs
to sit flat on either 1x2" end, perhaps raised on a parallel.

If you pushed the block up against a square inside corner so both the
rod and the indicator make contact and zero the indicator, then flip
the block over, the indicator will still read zero.

Do that to a corner which isn't quite square and the indicator will
show (+) the error one way, (-) the error the other, or twice the
total.

You don't have to use a 1-2-3 block, all that's necessary is that the
top and bottom are parallel. You could machine a block and check
parallelism with the indicator.

Jim Wilkins