Z Axis

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Maintenance Z-axis:

It's good to occasionally do a quick check for perpendicular of the Z axis with a square. But the best technique is to put a dial indicator on an arm that is attached to a shaft that is chucked up in the router/spindle. Swing the dial indicator around an area on your table that has been machined level. You will be able to tell whether your Z axis is square sideways and backwards and forwards or needs to be adjusted. Get the lateral direction level first leaving the top two mounting bolts slightly loose. Then tap the top of the frame gently one direction of the other to get the front/back adjustment right. You may have to do this process again after surfacing the table with your new adjustment in order to have a flat surface for measurement. If you are using a bleeder board vacuum system, the vacuum needs to be active when you are carrying out the measurements.

Each bearing on your Z-axis should be tight and riding two surfaces for the length of the rail. If after several weeks use the bearings do not appear to be tightly engaging the car, the bearings can be tightened by rotating their eccentric bushings slightly. Just rotate each of the bushings (they are the large nut just outside the bearing) counter-clockwise slightly to tighten the Z car up.

Check for up and down play in the Z axis that can come from backlash on the rack and pinions. The stepper motor pivots into the rack and can be tightened to remove any backlash.

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