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Z-Axis Gib
Please reference our https://tormach.atlassian.net/wiki/spaces/IMK/pages/2463596570 Mill Gib/AC Bearing Adjustment and Backlash Compensation page for guidance on the adjustment process.
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If you have chatter in a straight line move in one axis, and chatter is present. Vet out all other factors first. If all else fails, a loose gib in the opposite gib from the direction you are running, could be loose, causing chatter. For example: Straight line tool path in X chatters - check for Y axis gib.
Please reference our https://tormach.atlassian.net/wiki/spaces/IMK/pages/2463596570 Mill Gib/AC Bearing Adjustment and Backlash Compensation page for guidance on the adjustment process.
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