Erratic movement of the Z axis

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bradders
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Erratic movement of the Z axis

Post by bradders » Thu 15 Oct , 2009 9:35 am

Customer writes ...............

There is something wrong with my Z axis. It is having a problem returning to the Z home position. The motor judders and the machine head staggers up and down until it gives up.

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bradders
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Re: Erratic movement of the Z axis

Post by bradders » Thu 15 Oct , 2009 9:35 am

The erratic movement of the Z axis usually means the there is a broken wire from the Z axis stepper motor to the control board. You can check this by removing the bottom right hand connector (Usually Orange in colour on older machines and marked up TB12 Axis 2) of the Baldor control board. The Baldor control board can be identified as the board with the 7 segment display board attached to it. There should be 4 wires on the Orange plug, these are wired in pairs and go to the stepper motor windings. With and electrical meter set on Resistance (Ohms), check each pair of windings, if the wiring / windings are OK then you should get around 2 Ohm’s resistance, if its Open Circuit then you have a broken wire. When we get this in the UK we usually replace all 4 wires.

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