besides backlash - Z-band fixed from LH miscalculate...read careful.

sorry my english is bad and Can't post links but you can figure out.  calculator -josefprusa - cz -- is source...this work to fix bands.  just have ab nut with spring and this no band at all.  I have no camera or I would post compare photographs.

Use Optimal layer height for your Z axis not a simple number e.g. .1796 or .2046 not .20 in slicer setting.

Joseph Prusa's tool will help you to select layer height in a way, that Z axis moves only by full step increments. Z axis isn't usually enabled during inactivity. If the axis is disabled during micro-step, axis jumps to the closest full step and introduce error. This effect is occurring to some extent even while leaving the Z axis motors enabled. This is most useful to machines with imperial leadscrews but also for unusual layer heights with metric leadscrews.
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Motor step angle 1.8 (200 per revolve)

Leadscrew pitch 1.41111 mm/revolution

Presets 5/16 1.44 imperial
Desired layer height
.3 mm
Z axis gear ratio 1:1
: 
Motor : Leadscrew (1:1 for direct drive - Prusa)
Layer height    Error over 10cm    Number of steps    Step length
0.2963                             0mm      42                                    0.00705555mm
0.3    +1.1217541105598867mm    42.523033309709426    0.00705555mm
0.3034                            0mm    43                                    0.00705555mm
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Desired layer height
.2 mm
: 
Motor : Leadscrew (1:1 for direct drive - Prusa)
Layer height    Error over 10cm    Number of steps    Step length
0.1976                                0mm         28                                 0.00705555mm
0.2    -1.2300958894401177mm    28.34868887313962    0.00705555mm
0.2046                          0mm                   29                            0.00705555mm

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Desired layer height
.1 mm
: 
Motor : Leadscrew (1:1 for direct drive - Prusa)
Layer height    Error over 10cm    Number of steps    Step length
0.09878                                 0mm    14                            0.00705555mm
0.1    -1.2300958894401177mm    14.17434443656981    0.00705555mm
0.1058                                 0mm    15                            0.00705555mm

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Desired layer height
.05 mm

: 
Motor : Leadscrew (1:1 for direct drive - Prusa)
Layer height    Error over 10cm    Number of steps    Step length
0.04939                              0mm                          7    0.00705555mm
0.05      -1.2300958894401177mm    7.087172218284905    0.00705555mm
0.05644                                 0mm                           8    0.00705555mm
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Banding due to calculate error gone.  Backlash  can be deal with w/ AB or no sloppiness nut (1/4 inch rod (ok but M5, M6, M8) -- no error without special value for z height.  ty ahead of time for thx and have nice day