What's the possibility of getting a Morse taper shank or whatever fits
the center hole of your RT and boring it to some good known diameter,
let's say .500 =/-.005. Then, when you want to center the table under
the spindle, stick a piece of .500 drill rod in the mill spindle and
move dials until the rod slips nicely into the hole. It may not be
diesel injector accurate, but do you do diesel injectors?

Pete Stanaitis
-----------------------

Bill Schwab wrote:
Hello all,

There is room for improvement in my RT setups. I would not mind
spending the money on a centering indicator (if it really works), but
round column mill-drill limits (correct me if I am wrong) appear to make
it pointless. However, I find that by mounting a DTI with the shaft
near the end of its dovetail, it works fairly well.

I would have an easier time given a spud of some type, but once it is
close, I seem to be able to align it, but there must be a smarter way. I
end up zeroing the dial to what I think is the correct position; it
helps me note deflections, but it probably causes trouble too. When
should I _not_ do that?

In case it helps, for indicating a vise, I find that I do best to always
bump during one direction of travel. Taking advice from various sources
(here and James Harvey's "Machine Shop Trade Secrets"), I align by feel
against the slots, then get the left bolt reasonably tight and the right
bolt just slightly past removing slack. Then I bump during translation,
but only with the table moving to the left. I do not try to gain ground
during the return pass because I seem to do more harm than good.

Is there a similar trick for locating the RT axis, such as making
changes only from one direction (left/front)??

Thanks,

Bill