Ahhhhh thank you! I had no idea!

I just made it visible. It seems like the infill speed was 50 mm/s, same as the print speed.

I'm printing with AMZ3D PLA at 200c. The filament label suggests to print between 180 to 210c. My travel speed is 120 mm/s.

Should I slow down the infill some more or tweak travel speed / temperature?

Thanks for the detailed explanation, I really appreciate it :)

Shown above is the wall perpendicular to the Y axis. This wall has several (apparently random) layers that are misaligned (not shifted!). All layers perpendicular to the Y axis show this displacement, though layers even slightly start to improve greatly.

This problem appears in prints from 0.1mm to 0.3mm layer heights. Slowing the printer down to ~20 mm/s does not help.

(As mentioned below, I suspected the Y axis belt to be too loose and tightened it as much as possible, but that doesn't seem to be enough...)

I would love some help either diagnosing or suggesting a fix. Thanks!

Printer: Monoprice Maker Select V2 (ie. Wanhao Duplicator i3 v2.1)

Material: PLA Amz3d

Slicer settings: I used the print that came with the SD card (1.gcode). This is repeatable with my own slicer settings as well:

generated by Slic3r 1.2.9 on Sun Apr 9 04:22:41 2017

avoid_crossing_perimeters = 0<br />
bed_shape = 0x0,200x0,200x200,0x200<br />
bed_temperature = 50<br />
before_layer_gcode = <br />
bottom_solid_layers = 3<br />
bridge_acceleration = 0<br />
bridge_fan_speed = 100<br />
bridge_flow_ratio = 1<br />
bridge_speed = 60<br />
brim_width = 0<br />
complete_objects = 0<br />
cooling = 1<br />
default_acceleration = 0<br />
disable_fan_first_layers = 3<br />
dont_support_bridges = 0<br />
duplicate_distance = 6<br />
end_gcode = ;End GCode\nM104 S0                     ;extruder heater off\nM140 S0                     ;heated bed heater off (if you have it)\nG91                                    ;relative positioning\nG1 E-1 F300                            ;retract the filament a bit before lifting the nozzle, to release some of the pressure\nG1 Z+0.5 E-5 X-20 Y-20 F[travel_speed] ;move Z up a bit and retract filament even more\nG28 X0 Y0                              ;move X/Y to min endstops, so the head is out of the way\nM84                         ;steppers off\nG90                         ;absolute positioning<br />
external_fill_pattern = rectilinear<br />
external_perimeter_extrusion_width = 0<br />
external_perimeter_speed = 50%<br />
external_perimeters_first = 0<br />
extra_perimeters = 1<br />
extruder_clearance_height = 20<br />
extruder_clearance_radius = 20<br />
extruder_offset = 0x0<br />
extrusion_axis = E<br />
extrusion_multiplier = 1<br />
extrusion_width = 0<br />
fan_always_on = 1<br />
fan_below_layer_time = 60<br />
filament_colour = #FFFFFF<br />
filament_diameter = 1.75<br />
fill_angle = 45<br />
fill_density = 20%<br />
fill_pattern = honeycomb<br />
first_layer_acceleration = 0<br />
first_layer_bed_temperature = 50<br />
first_layer_extrusion_width = 0<br />
first_layer_height = 90%<br />
first_layer_speed = 15<br />
first_layer_temperature = 200<br />
gap_fill_speed = 10<br />
gcode_arcs = 0<br />
gcode_comments = 0<br />
gcode_flavor = reprap<br />
infill_acceleration = 0<br />
infill_every_layers = 1<br />
infill_extruder = 1<br />
infill_extrusion_width = 0<br />
infill_first = 0<br />
infill_only_where_needed = 1<br />
infill_overlap = 15%<br />
infill_speed = 50<br />
interface_shells = 0<br />
layer_gcode = <br />
layer_height = 0.2<br />
max_fan_speed = 100<br />
max_print_speed = 60<br />
max_volumetric_speed = 0<br />
min_fan_speed = 35<br />
min_print_speed = 10<br />
min_skirt_length = 5<br />
notes = <br />
nozzle_diameter = 0.4<br />
octoprint_apikey = <br />
octoprint_host = <br />
only_retract_when_crossing_perimeters = 1<br />
ooze_prevention = 0<br />
output_filename_format = [input_filename_base].gcode<br />
overhangs = 1<br />
perimeter_acceleration = 0<br />
perimeter_extruder = 1<br />
perimeter_extrusion_width = 0<br />
perimeter_speed = 30<br />
perimeters = 2<br />
post_process = <br />
pressure_advance = 0<br />
raft_layers = 0<br />
resolution = 0<br />
retract_before_travel = 2<br />
retract_layer_change = 0<br />
retract_length = 2<br />
retract_length_toolchange = 10<br />
retract_lift = 0<br />
retract_restart_extra = 0<br />
retract_restart_extra_toolchange = 0<br />
retract_speed = 40<br />
seam_position = random<br />
skirt_distance = 6<br />
skirt_height = 1<br />
skirts = 1<br />
slowdown_below_layer_time = 5<br />
small_perimeter_speed = 7<br />
solid_infill_below_area = 70<br />
solid_infill_every_layers = 0<br />
solid_infill_extruder = 1<br />
solid_infill_extrusion_width = 0<br />
solid_infill_speed = 10<br />
spiral_vase = 0<br />
standby_temperature_delta = -5<br />
start_gcode = G21        ;metric values\nG90        ;absolute positioning\nM82        ;set extruder to absolute mode\nM107       ;start with the fan off\nG28 X0 Y0  ;move X/Y to min endstops\nG28 Z0     ;move Z to min endstops\nG1 Z15.0 F[travel_speed] ;move the platform down 15mm\nG92 E0                  ;zero the extruded length\nG1 F[travel_speed]\n;Put printing message on LCD screen\nM117 Printing...\n<br />
support_material = 1<br />
support_material_angle = 0<br />
support_material_contact_distance = 0.2<br />
support_material_enforce_layers = 0<br />
support_material_extruder = 1<br />
support_material_extrusion_width = 0<br />
support_material_interface_extruder = 1<br />
support_material_interface_layers = 3<br />
support_material_interface_spacing = 0<br />
support_material_interface_speed = 100%<br />
support_material_pattern = pillars<br />
support_material_spacing = 2.5<br />
support_material_speed = 30<br />
support_material_threshold = 0<br />
temperature = 190<br />
thin_walls = 1<br />
threads = 4<br />
toolchange_gcode = <br />
top_infill_extrusion_width = 0<br />
top_solid_infill_speed = 15<br />
top_solid_layers = 3<br />
travel_speed = 80<br />
use_firmware_retraction = 0<br />
use_relative_e_distances = 0<br />
use_volumetric_e = 0<br />
vibration_limit = 0<br />
wipe = 0<br />
xy_size_compensation = 0<br />
z_offset = 0

For sure! My FH has an Ender 3 3D printer. If you don't already have one, the Ender series is pretty good, however, you will have to assemble at least parts of it yourself. Then I actually found the file for this lanter on a website called Thingiverse here. We bought white PLA material off of Amazon and printed them. You just download the file and put it onto a microSD card, insert it into the printer and print. Once the top and bottom were printed (after a few trials and error) I primed and spray painted them rose gold.

We have printed a few things for the wedding so if you want to know more feel free to shoot me a message and I can send more pics and links :)

Amz3D. Gone through about 4 spools of different colors, solid brand imo.

https://www.amazon.ca/1-75mm-White-PLA-Printer-Filament/dp/B01BZO8O3O/ref=sr_1_1?s=electronics&ie=UTF8&qid=1503881382&sr=1-1