[beanbag]

Hello folks,

The XY stage on one of the Tormachs I use* seems to be loose. By this, I mean that if I put an indicator on the spindle touching a vise, and then grab the vise and yank it towards and away from me (y direction), the table seems to move by .005, while making a thunking sound. This has also happened on the other Tormach I use* and I was able to fix that by tightening the X gib, even though the looseness is in the y direction. This time, I loosened (ccw) the x gib screw on the right, and tightened the one on the left a few turns worth, and it didn't seem to do anything. In fact, before the machine had about .002 backlash in x (based on stepping .001 at a time) and now it increased to .003 (according to the tormach manual, the gib is too tight when the backlash starts increasing).

Could the screw mechanism in the y direction be loose instead? The machine is probably about 1 yr old, but gets used by a lot of people

* This is a communal tormach, so I am not allowed to do extensive fixes, yet the staff at the location is not well trained on this machine and probably wouldn't fix it anyways.

[twocik]

The vise isn't a good reference point to check for backlash, I'd measure from the table. Any vise if pushed on will move a little bit, but .005" is a lot. Here's a few things to check

Tighten the preload on each ballscrew, see Tormach manual 9.5.6. Check the socket head screws on each ballscrew nut and that each motor housing is tight.

[GJeff]

if you can move your table around then your gibs are loose, there's no need for precision testing them yet by using increased backlash as an indicator until BOTH have been tightened to a reasonable degree that you're not clunking the table around freehand.