Re: [CAD_CAM_EDM_DRO] Re: Z-axis CNC conversion on a mill-drill: a challenge (long)

Hi Dan,

Interesting! Offsetting the pinion shaft to get it nearer to the rack to
take out the backlash of the rack and pinion sounds good.

I can see that the left hand side eccentric bushing will be easy but where
did you put the right hand side eccentric? After reducing the right hand
side shaft diameter of the pinion, and making a corresponding eccentric
bushing, how and where did you install the right hand side eccentric
bushing?

Approximately how much (in inches or mm) did you offset the eccentric from
the original position?

Did you put back the coil spring on the left hand side of the pinion shaft?
If not, how did you counter balance the weight of the quill? Will the quill
not lower down on its own after being powered down?

Can you send me the article about solving the mill drill z axis backlash as
well as the pictures on the X and Y axis ball nut backlash elimination?

TIA, WT

----- Original Message -----
From: Dan Mauch
To: CAD_CAM_EDM_DRO@yahoogroups.com
Sent: Sunday, April 29, 2007 10:28 PM
Subject: Re: [CAD_CAM_EDM_DRO] Re: Z-axis CNC conversion on a mill-drill: a
challenge (long)

(Snip)......
On my mill drill, in addition to the quill modification, I did a couple of
novel things to make the ballscrews zero backlash.
(Snip)......
Now that I think about it I have some pictures of this somewhere. If
interested I can email them to you.
Yes I mentioned before that after the new pinion shaft was installed and the
eccentric bushing were rotated and then locked inplace that I had to
elongage the holes about 1/32" on the worm wheel housing to reduce the worm
to worm wheel backlash.

Dan Mauch
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www.camtronics-cnc.com
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