On 2010-07-29, Ignoramus6705 wrote:
On 2010-07-29, RogerN wrote:

[ ... ]

I would think it is minimal since an entire turn of the handwheel is 0.2" or
so. I would guess belt stretch to make less than a half thou difference.
But if it does affect your parts, you have the capability to put DRO scales
on your mill and use them with EMC2 instead of the motor encoders. That's
what my mill has, an Anilam control with Anilam DRO scales , the motors have
tachometers on them, they are stable even with backlash.

Roger, there is no handweel attached to the ballscrews.

The "virtual" handwheel. :-) It is still 0.200" per revolution
of the ballscrew or the nut.

If yours is like mine -- the ballscrew for the X-axis does not
rotate at all -- instead the ball *nut* rotates in matched bearings.
And the ballscrew has a telescoping flat spring steel cover to keep
swarf off of it.

Y-axis, however, does have a rotating ballscrew.

BTW -- looking at the photo you just (re)posted of the mill on
the truck or trailer I now see that the Y-axis motor has the pulley end
towards the vertical ways in the back instead of facing out towards the
operator as mine does. I still should be able to mount the motor on the
side of the knee -- if I can find a flat enough surface. :-)

Enjoy,
DoN.

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