Z axis squaring help?

[JimFabLabFulton]

I need help on how to square the z axiz. We have a prs alpha 4896 Electricty just hooked up first surfacing pass complete and I have some obvious tooling marks, so I know my z axis is not square. I have a columbo 5hp spindle and my surface is plywood and 2 sheets mdf each piece being 3/4 inch.

[Brady Watson]

You may find this helpful: http://www.talkshopbot.com/forum/showthread.php?t=16866

-B

[JimFabLabFulton]

Thank you Brady,

I chucked up a dial gauge and rotated it in a 8 inch or so circle and found I was off around .07". After some loosing and tighting of spindle it is much closer .02 or so, I am going to resurface and see what I get. Has anyone adjusted the eccentric cam rollers to get better alignment?

[Brady Watson]

The cam rollers on the bottom of the YZ car should be snug to the bottom rail. Not loose; not king kong tight either. This should be done before anything else.

The only things you should be messing with to true up the Z is either adjusting the tilt of the spindle in the Y direction - or if that doesn't get you where you need to be, pulling off the spindle and setting the adapter plate to spindle so that they are perfectly parallel to each other. Then adjust with square.

If the ridges show up in the other direction (parallel to Y), then that is more involved, but it is usually because the YZ car v-rollers are loose.

-B