On Tue, 25 Nov 2008 23:36:20 -0800, "Michael Koblic"
wrote:

Gunner Asch wrote:

Clamp around the quill, not the spindle. if you have to, use a hose
clamp and a bit of strap to make something to hang your indicator
from.

that is what I do. On the other hand..you can indeed chuck your
indicator in a drill chuck..but put the spindle into lock mode...with
the motor off, put it i n the lowerst gear you have. less likely for
the spindle to turn. Its pretty sure that your spindle turned while
you were indicating.

Or your mill is way way way out of alighment G


Thanks.

I should fill in some details:

1) I trammed the table and it is level to within 1/1000" - I checked it
again just to make sure.
2) The vise is on a base with two slots and rotates. Mindful of the advice
in the MIT clips I did just that - gradually tightened the screws that
control the rotation and gently tapped the vise with a dead blow hammer to
make the corrections.
3) I cannot stop the spindle rotating, even in the lowest gear.
4) I adjusted the gibs on day 1 to the best of my ability. I cannot
demonstrate play in any of the axes. But...will check again!

The common theme appears to be that the source of the error is likely the
movement of the indicator as used currently. I shall fix it and repeat.


Pro shops get rid of the rotating table some vises are mounted on. Only
if you need to spin something out of square does the swivel base go back
on..or they use a rotory table.

what mill do you have? If its a bridgeport, you can intentionally jam
the gears by putting it in low range with the overhead selector around
the draw bar on the head and putting it in low range with the selector
on the right side of the head. Or pull the brake and hold it with a
bungee cord. shrug

But the strap and hoseclamp around the quill works quickly and easily
and avoids the spindle entirely.

Gunner

"They couldn't hit an elephant at this dist..."
Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania