On Mon, 29 Oct 2007 17:44:54 -0400, Bill Schwab
wrote:
snip
It is indeed a great book, but AFAICT, it does not answer my question.
I am asking for more detailed advice on *how* to "move the x- and y-axis
until a zero reading is obtained." The part about backlash is
well-taken (and I'm somewhat surprised to say becoming second nature to
me). In particular, I am interested in any opinions you and others have
on when to re-zero the indicator (which I find helpful when looking at
it upside-down and backwards), and when _not_ to mess with it. It is
probably as simple as always doing it with or against backlash, but I do
not see it yet. I am almost certain I am wasting steps.
snip
One man's wasted time is another man's doublechecking....

What you may want to try is inserting a "good" #2MT [most of the
smaller RTs now sold in the US have a #2MT -- YMMV] and
indicating off the external/end. Because the table will [or
should be] locked when using the RT, x/y back lash should have no
effect if you are using a test indicator. I would not try to
rezero the indicator, rather just keep it at the same reading,
i.e. no needle movement as you rotate the spindle. Indicate the
x [side to side] first and note the needle position. Then rotate
the spindle so the indicator is to the front, and adjust the y
until the reading is the same. You may have to go through this
cycle several times as the x readings will change as you run the
y in and out. On the last adjustment cycle the reading should
remain constant, and then check with the indicator to the back,
possibly with a mirror that the needle is not moving or is moving
within the accuracy you desire [or will accept].
http://www.use-enco.com/CGI/INPDFF?P...PARTPG=INLMK32
another possibility is a high quality center that you use just
for set-up
http://www.use-enco.com/CGI/INPDFF?P...MITEM=251-3042
for imports click on
http://littlemachineshop.com/product...Product+Search
I found the 2394 to be ground as close as the Jacobs, but your
part may be different.

The problem with a co-ax style indicator is these are loooooong
and you may not be able to get one into position, although using
a #2MT/3/8 collet will gain you some space over a drill chuck or
ER adapter.
for a clone click on
http://hhip.com/products/product_vie...uctID=400-0020
http://www.use-enco.com/CGI/INSRIT?P...&PMPXNO=952232
http://www.use-enco.com/CGI/INPDFF?P...MITEM=607-4907
for the real thing click on
http://www.blakemanufacturing.com/pages/aboutus.html


Unka' George [George McDuffee]
============
Merchants have no country.
The mere spot they stand on
does not constitute so strong an attachment
as that from which they draw their gains.

Thomas Jefferson (1743-1826),
U.S. president. Letter, 17 March 1814.