Ungeared extruders do that, even with 16:1 ustepping. You can play with the extruder current to tweak the way it looks, but it won't go away completely unless you use a geared extruder which increases the "resolution" of the extrusion process.
You may have a bit of over-extrusion going on, too.
Edited 1 time(s). Last edit at 06/21/2017 10:17AM by the_digital_dentist.
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