Strange z axis "wobbles"

[andyroo189]

Hi!

I've had my A10 for about 6 weeks now and have been working towards getting the print quality better.

I have one problem that I don't know where to start, and it looks like z axis banding, but the "period" of the bands is quite wide. Please see the picture of what should be a straight edge cylinder - and there are wobbles in the print.

Any help in where to start getting this sorted would be much appreciated.

[AFewSkroosLoose]

The period looks pretty close to 8mm or so. The 2mm pitch 4 start z axis lead screw will give 8mm of travel per one full revolution. Could it be that it is either bent or possibly misaligned with z axis motor shaft via the coupling? This could cause binding or tightness in some places, put stresses then on your x axis and possibly yank it around a little to produce your wobble? Im just guessing here, but check your screw straightness and alignment with the other elements - motor and coupling, brass lead screw nut, and top bearing.