I am curious what could be causing these seemingly random gaps to print in the side wall in only certain areas of the print. F-350 single-head extruder. Hatchbox PLA Silver filament in a filament dryer.
This is a sub-symptom of a clogged hotend/nozzle. You will need to figure out if the hotend is clogged, and what is causing the clog, usually improper retraction settings or the hotend’s PTFE liner degrading from overheat. Some other possible causes include print temp too low, a buildup of a previous filament that did not get cleaned out (especially if that required a higher print temp), and heat creep (another sub-symptom with an underlying cause). I would also check your filament path between the spool and toolhead to make sure that it is not binding up anywhere and does not have excessive tension.
Whilst the above advice is very useful, it seems the occurrence of the problem is also related to features in the model itself. It’s more than a coincidence that these failures occur at the same or similar places and these model features could be exposing an inherent fault in the filament delivery. The circular surface pattern (looks like shimmer) is almost certainly caused by the filament feed gearing.
