The lines are called Z-Striping and are caused by Z-Axis Wobble, they are formed as the lead screw wobbles moving the nozzle when it turns in its rotation..
I solved my Z-Stripping by Wrapping a single layer of electrician tape on the Z-Axis lead-screws before inserting them into couplers.
Then for the it to look good cut of the excess tape that was still outside the couplers and removed from lead-screw.