If you have problems with Z banding then I recommend fixing it as I have done. I used some fuel line for a rc airplane to connect the Z axis rod to the motor. I was able to identify this as my problem by watching the motor rock back and forth as the table was going up or down. When the motor is flexing back and forth do to the rigid coupler it causes minuscule movements on the table that transalte into the surface of the part. This is a very worthwhile fix and will not only improve your High resolution prints but also the .3mm layer prints as well. I am cranking out .1mm layer prints extremely well and I am very pleased with my da vinci since doing this mod.

They also make flexible aluminum couplers that work the same way but won't slip under high acceleration of manual moves.

http://www.amazon.com/Funnytrue-Flexibl … od+coupler