<p>Are these vertical lines described as "banding"?</p>

<p>Would the most likely culprit be the extruder?</p>

<p>FWIW, this was printed in "vase mode".</p>

<p><a href="https://i.stack.imgur.com/0ZCPF.jpg" rel="noreferrer" title="&quot;Vase mode, PLA"><img src="https://i.stack.imgur.com/0ZCPF.jpg" alt="Vase mode, PLA" title="&quot;Vase mode, PLA"></a></p>

[{'answer_id': 5824, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 3, 'selected': False, 'text': '<p>Banding usually refers to Z banding and manifests itself in a wavy/non-straight wall in Z direction: </p>\n\n<p><a href="https://i.stack.imgur.com/KYp55.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/KYp55.jpg" alt="Z-banding"></a></p>\n\n<p>This sort of banding is related to mechanical or design issues of the printer (lead screw (nuts), belts, play, etc.)</p>\n\n<p>Your print, however, shows local thicker walls. It appears that these local thicker parts are related to the change in direction of the print head. A 3D printer does not print curved lines or arcs (although <a href="http://reprap.org/wiki/G-code#G2_.26_G3:_Controlled_Arc_Move" rel="noreferrer">G-codes do exist for arc movement</a>), all movements are straight lines. So the cylinder consists of straight lines. By rendering the cylinder with more triangels you could increase the amount of straight lines to form a better approximation of the cylinder circumference. You could also try to lower the printing speed, but since you did not post any printing parameters that will be a guess.</p>\n'}, {'answer_id': 5887, 'author': 'Roger', 'author_id': 10533, 'author_profile': 'https://3dprinting.stackexchange.com/users/10533', 'pm_score': 3, 'selected': True, 'text': '<p>Ok, so it turns out that this was caused by a problem in my stepper motor drivers, which results in missed steps, as described on <a href="https://web.archive.org/web/20171127173338/http://www.engineerination.com/2015/02/drv8825-missing-steps.html?m=1" rel="nofollow noreferrer">this guy\'s blog</a></p>\n\n<p>The fix was to hook up these "TL Smoother" modules (I got <a href="https://rads.stackoverflow.com/amzn/click/B071WG3SZQ" rel="nofollow noreferrer">these particular ones</a> from amazon but there are a bazillion clones)</p>\n\n<p>After hooking up TL Smoother, this is what the print looks like:</p>\n\n<p><a href="https://i.stack.imgur.com/B52kB.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/B52kB.jpg" alt="enter image description here"></a></p>\n'}]
['https://3dprinting.stackexchange.com/questions/5822', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/10533/']