decrease in print quality with FW 3.9.0

[rcaslis]

Printer type: MK3 Printer firmware version: 3.9.0 vs 3.8.1 SD card Upgrades: BMG extruder variant, Vesconite bearings, cable chains

I've seen a significant decrease in quality after moving to 3.9.0.

Attached is a picture of the same piece, printed on the same printer, with the same filament, with the same gcode about 12 hours apart. The top piece is with 3.9.0 while the bottom piece is 3.8.1. I did stop the print for the 3.9.0 version before the top layers since the problem was already evident.

It must be the conversion to LA15 that causes the problem, but I'm uncertain of how to proceed past that. For reference, the gcode uses a K factor of 28.

I've also attached the gcode.

What can be done to improve the quality back to 3.8.1 behavior?

crusher.gcode.txt

[awenelo]

Edit: Prusaslicer has updated the filament profiles, can you reslice the model using a System Presets filament? (no need to calibrate anymore) Also, what filament are you using?

Linear advance can be calibrated following instructions here. Can you calibrate it then try again? You can set the K value in pursaslicer in Filament settings -> Custom Gcode(you need to be in expert mode)

[rcaslis]

Edit: Prusaslicer has updated the filament profiles, can you reslice the model using a System Presets filament? (no need to calibrate anymore) Also, what filament are you using?

When my printer isn't busy anymore I'll try reslicing with the system presets filament.

It's a shame I have to though... I have a library of gcode for my current project and I don't look forward to reslicing and re-printing them to test. Many are 3-10 hour prints that I've printed a half-dozen times tweaking the slicer settings each time to get it just right. Suddenly having a known quantity become unknown again is frustrating.

I'm using PLA from https://coexllc.com/. Decent filament, but it prints hot (~220c).

Linear advance can be calibrated following instructions here. Can you calibrate it then try again? You can set the K value in pursaslicer in Filament settings -> Custom Gcode(you need to be in expert mode)

I looked into that last night. I generated the k-factor calibration pattern using the defaults and honestly all of them looked poor, but a K factor of 0 looked best. Using that, my print was complete trash.

[awenelo]

A K factor of 0 disables LA. Prusaslicer sets the K factor to .06, try something around that.

If you have Visual Studio Code, you can replace the K value (the only really important change) by: Ctrl + K Ctrl + O and selecting the directory Ctrl + Shift + F Clicking the arrow to the left of "search" In "search" typing M900 K28 In "replace" typing M900 K0.06 Ctrl + Alt + Enter

[rcaslis]

I can update the gcode easy enough (even using notepad works), but isn't 3.9.0 supposed to automatically convert old LA10 values to something sensible for LA15?

[awenelo]

I believe that to convert, it needs to know what firmware version the Gcode is for. For automatic conversion, I believe that there needs to be M115 U3.8.1; in the Gcode.

[rcaslis]

I believe that to convert, it needs to know what firmware version the Gcode is for. For automatic conversion, I believe that there needs to be M115 U3.8.1; in the Gcode.

That's super interesting. I'll try that out once my printer is done with it's current print.

[mw2matze]

For me, after upgrading the Firmware the Quality decreased dramaticly... As you can see in the picture. (top is 3.8.1, bot is 3.9.0 i printed the same file, with the new config in prusaslicer)

[awenelo]

What profiles were those printed with and when were they sliced?

[mw2matze]

I sliced them yesterday with these Settings :

generated by PrusaSlicer 2.2.0+win64 on 2020-05-28 at 18:25:22 UTC

avoid_crossing_perimeters = 0 bed_custom_model = bed_custom_texture = bed_shape = 0x0,250x0,250x210,0x210 bed_temperature = 90 before_layer_gcode = ;BEFORE_LAYER_CHANGE\nG92 E0.0\n;[layer_z]\n\n between_objects_gcode = bottom_fill_pattern = rectilinear bottom_solid_layers = 4 bottom_solid_min_thickness = 0.5 bridge_acceleration = 1200 bridge_angle = 0 bridge_fan_speed = 50 bridge_flow_ratio = 0.9 bridge_speed = 60 brim_width = 0 clip_multipart_objects = 1 colorprint_heights = compatible_printers_condition_cummulative = "printer_notes=~/.PRINTER_VENDOR_PRUSA3D./ and printer_notes=~/.PRINTER_MODEL_MK3./ and nozzle_diameter[0]==0.4";"nozzle_diameter[0]!=0.6 and printer_model!=\"MK2SMM\" and printer_model!=\"MINI\" and ! (printer_notes=~/.PRINTER_VENDOR_PRUSA3D./ and printer_notes=~/.PRINTER_MODEL_MK(2.5|3)./ and single_extruder_multi_material)" complete_objects = 0 cooling = 1 cooling_tube_length = 20 cooling_tube_retraction = 40 default_acceleration = 2400 default_filament_profile = "Prusament PLA" default_print_profile = 0.15mm QUALITY @MK3 deretract_speed = 0 disable_fan_first_layers = 3 dont_support_bridges = 1 draft_shield = 0 duplicate_distance = 6 elefant_foot_compensation = 0.2 end_filament_gcode = "; Filament-specific end gcode" end_gcode = G1 X0 Y210 F7200\nG1 E2 F5000\nG1 E2 F5500\nG1 E2 F6000\nG1 E-15.0000 F5800\nG1 E-20.0000 F5500\nG1 E10.0000 F3000\nG1 E-10.0000 F3100\nG1 E10.0000 F3150\nG1 E-10.0000 F3250\nG1 E10.0000 F3300\n\nM702 C\n\nG4 ; wait\nM221 S100 ; reset flow\nM900 K0 ; reset LA\nM104 S0 ; turn off temperature\nM140 S0 ; turn off heatbed\nM107 ; turn off fan\n; Lift print head a bit\n{if layer_z < max_print_height}G1 Z{z_offset+min(layer_z+30, max_print_height)}{endif} ; Move print head up\nG1 X0 Y200 F3000 ; home X axis\nM84 ; disable motors ensure_vertical_shell_thickness = 1 external_perimeter_extrusion_width = 0.55 external_perimeter_speed = 120 external_perimeters_first = 0 extra_loading_move = -25 extra_perimeters = 0 extruder_clearance_height = 20 extruder_clearance_radius = 45 extruder_colour = "" extruder_offset = 0x0 extrusion_axis = E extrusion_multiplier = 0.99 extrusion_width = 0.55 fan_always_on = 1 fan_below_layer_time = 20 filament_colour = #FF8000 filament_cooling_final_speed = 3.4 filament_cooling_initial_speed = 2.2 filament_cooling_moves = 4 filament_cost = 28.69 filament_density = 1.23 filament_deretract_speed = nil filament_diameter = 1.75 filament_load_time = 0 filament_loading_speed = 28 filament_loading_speed_start = 3 filament_max_volumetric_speed = 25 filament_minimal_purge_on_wipe_tower = 15 filament_notes = "" filament_ramming_parameters = "120 100 6.6 6.8 7.2 7.6 7.9 8.2 8.7 9.4 9.9 10.0| 0.05 6.6 0.45 6.8 0.95 7.8 1.45 8.3 1.95 9.7 2.45 10 2.95 7.6 3.45 7.6 3.95 7.6 4.45 7.6 4.95 7.6" filament_retract_before_travel = nil filament_retract_before_wipe = nil filament_retract_layer_change = nil filament_retract_length = nil filament_retract_lift = nil filament_retract_lift_above = nil filament_retract_lift_below = nil filament_retract_restart_extra = nil filament_retract_speed = nil filament_settings_id = Covid19HeadbandPETG filament_soluble = 0 filament_toolchange_delay = 0 filament_type = PETG filament_unload_time = 0 filament_unloading_speed = 90 filament_unloading_speed_start = 100 filament_vendor = Prusa Polymers filament_wipe = nil fill_angle = 45 fill_density = 100% fill_pattern = rectilinear first_layer_acceleration = 1200 first_layer_bed_temperature = 85 first_layer_extrusion_width = 0.42 first_layer_height = 0.2 first_layer_speed = 60 first_layer_temperature = 265 gap_fill_speed = 160 gcode_comments = 0 gcode_flavor = marlin gcode_label_objects = 0 high_current_on_filament_swap = 0 host_type = octoprint infill_acceleration = 2400 infill_every_layers = 1 infill_extruder = 1 infill_extrusion_width = 0.55 infill_first = 0 infill_only_where_needed = 0 infill_overlap = 27% infill_speed = 240 inherits_cummulative = "0.20mm SPEED @MK3";"Prusament PETG";"Original Prusa i3 MK3S MMU2S Single" interface_shells = 0 layer_gcode = ;AFTER_LAYER_CHANGE\n;[layer_z] layer_height = 0.2 machine_max_acceleration_e = 10000,5000 machine_max_acceleration_extruding = 1500,1250 machine_max_acceleration_retracting = 1500,1250 machine_max_acceleration_x = 9000,960 machine_max_acceleration_y = 9000,960 machine_max_acceleration_z = 500,1000 machine_max_feedrate_e = 120,120 machine_max_feedrate_x = 500,100 machine_max_feedrate_y = 500,100 machine_max_feedrate_z = 12,12 machine_max_jerk_e = 2.5,4.5 machine_max_jerk_x = 5,8 machine_max_jerk_y = 5,8 machine_max_jerk_z = 0.2,0.4 machine_min_extruding_rate = 0,0 machine_min_travel_rate = 0,0 max_fan_speed = 50 max_layer_height = 0.25 max_print_height = 210 max_print_speed = 300 max_volumetric_speed = 0 min_fan_speed = 30 min_layer_height = 0.07 min_print_speed = 25 min_skirt_length = 4 notes = nozzle_diameter = 0.4 only_retract_when_crossing_perimeters = 0 ooze_prevention = 0 output_filename_format = {input_filenamebase}{layerheight}mm{filamenttype[0]}{printermodel}{print_time}.gcode overhangs = 1 parking_pos_retraction = 85 perimeter_acceleration = 1000 perimeter_extruder = 1 perimeter_extrusion_width = 0.55 perimeter_speed = 160 perimeters = 2 post_process = print_host = print_settings_id = Covid19Headband printer_model = MK3SMMU2S printer_notes = Don't remove the following keywords! These keywords are used in the "compatible printer" condition of the print and filament profiles to link the particular print and filament profiles to this printer profile.\nPRINTER_VENDOR_PRUSA3D\nPRINTER_MODEL_MK3\n printer_settings_id = Covid19Headband printer_technology = FFF printer_variant = 0.4 printer_vendor = printhost_apikey = printhost_cafile = raft_layers = 0 remaining_times = 1 resolution = 0 retract_before_travel = 1 retract_before_wipe = 0% retract_layer_change = 1 retract_length = 2 retract_length_toolchange = 3 retract_lift = 0.6 retract_lift_above = 0 retract_lift_below = 209 retract_restart_extra = 0 retract_restart_extra_toolchange = 0 retract_speed = 55 seam_position = nearest serial_port = serial_speed = 250000 silent_mode = 0 single_extruder_multi_material = 0 single_extruder_multi_material_priming = 0 skirt_distance = 2 skirt_height = 3 skirts = 1 slice_closing_radius = 0.049 slowdown_below_layer_time = 10 small_perimeter_speed = 90 solid_infill_below_area = 0 solid_infill_every_layers = 0 solid_infill_extruder = 1 solid_infill_extrusion_width = 0.55 solid_infill_speed = 120 spiral_vase = 0 standby_temperature_delta = -5 start_filament_gcode = "M900 K{if printer_notes=~/.PRINTER_MODEL_MINI./ and nozzle_diameter[0]==0.6}0.12{elsif printer_notes=~/.PRINTER_MODEL_MINI./}0.2{elsif nozzle_diameter[0]==0.6}0.05{else}0.12{endif} ; Filament gcode LA 1.5\n{if printer_notes=~/.PRINTER_MODEL_MINI./};{elsif printer_notes=~/.PRINTER_HAS_BOWDEN./}M900 K200{elsif nozzle_diameter[0]==0.6}M900 K24{else}M900 K45{endif} ; Filament gcode LA 1.0" start_gcode = M862.3 P "[printer_model]" ; printer model check\nM862.1 P[nozzle_diameter] ; nozzle diameter check\nM115 U3.8.1 ; tell printer latest fw version\nG90 ; use absolute coordinates\nM83 ; extruder relative mode\nM104 S[first_layer_temperature] ; set extruder temp\nM140 S[first_layer_bed_temperature] ; set bed temp\nTx\nM190 S[first_layer_bed_temperature] ; wait for bed temp\nM109 S[first_layer_temperature] ; wait for extruder temp\nG28 W ; home all without mesh bed level\nG80 ; mesh bed leveling\n\n;go outside print area\nG1 Y-3.0 F1000.0\nG1 Z0.4 F1000.0\n; select extruder\nTc\n; purge line\nG1 X55.0 F2000.0\nG1 Z0.3 F1000.0\nG92 E0.0\nG1 X240.0 E25.0 F2200.0\nG1 Y-2.0 F1000.0\nG1 X55.0 E25 F1400.0\nG1 Z0.20 F1000.0\nG1 X5.0 E4.0 F1000.0\n\nM221 S{if layer_height<0.075}100{else}95{endif}\nG92 E0.0\n support_material = 1 support_material_angle = 0 support_material_auto = 1 support_material_buildplate_only = 1 support_material_contact_distance = 0.1 support_material_enforce_layers = 0 support_material_extruder = 0 support_material_extrusion_width = 0.35 support_material_interface_contact_loops = 0 support_material_interface_extruder = 0 support_material_interface_layers = 2 support_material_interface_spacing = 0.2 support_material_interface_speed = 100% support_material_pattern = rectilinear support_material_spacing = 2 support_material_speed = 60 support_material_synchronize_layers = 0 support_material_threshold = 55 support_material_with_sheath = 0 support_material_xy_spacing = 50% temperature = 265 thin_walls = 0 threads = 12 thumbnails = toolchange_gcode = top_fill_pattern = rectilinear top_infill_extrusion_width = 0.5 top_solid_infill_speed = 100 top_solid_layers = 5 top_solid_min_thickness = 0.6 travel_speed = 250 use_firmware_retraction = 0 use_relative_e_distances = 1 use_volumetric_e = 0 variable_layer_height = 1 wipe = 1 wipe_into_infill = 0 wipe_into_objects = 0 wipe_tower = 1 wipe_tower_bridging = 10 wipe_tower_no_sparse_layers = 0 wipe_tower_rotation_angle = 0 wipe_tower_width = 60 wipe_tower_x = 170 wipe_tower_y = 125 wiping_volumes_extruders = 70,70 wiping_volumes_matrix = 0 xy_size_compensation = 0 z_offset = 0

[mw2matze]

What profiles were those printed with and when were they sliced?

:/ i don't know, what to do.

[awenelo]

Looking at the start G-codes, it appears as if you are giving the printer a LA1.5 K value, but telling it that the G-code was sliced for 3.8.1. I believe that this causes the printer to believe that it was sliced for LA1.0, so it converts the values (that it thinks are LA1.0) to LA1.5, even though they are already LA1.5, causing different K values than ideal.

In the printer start G-code, can you change the line M115 U3.8.1 ; tell printer latest fw version to M115 U3.9.0 ; tell printer latest fw version and re-slice your file?

[leptun]

The M115 command doesn't influence Linear Advance

[awenelo]

How does it decide to auto-convert?

[leptun]

If you provide two M900 commands, the new firmware accepts the first one and older firmware accepts the last one. This is what you might encounter in a start gcode now:

M900 K0.06 ; will be accepted by FW >=3.9.0
M900 K30 ; will be accepted by FW <3.9.0 or by >=3.9.0 if the LA1.5 one is missing

[mw2matze]

Ok, so we still don't know, why this happens? Here is my cutdown Gcode i used for both prints:

[mw2matze]

; generated by PrusaSlicer 2.2.0+win64 on 2020-05-27 at 08:06:16 UTC

;

; external perimeters extrusion width = 0.55mm ; perimeters extrusion width = 0.55mm ; infill extrusion width = 0.55mm ; solid infill extrusion width = 0.55mm ; top infill extrusion width = 0.50mm ; support material extrusion width = 0.35mm ; first layer extrusion width = 0.42mm

M73 P0 R263 M201 X9000 Y9000 Z500 E10000 ; sets maximum accelerations, mm/sec^2 M203 X500 Y500 Z12 E120 ; sets maximum feedrates, mm/sec M204 P1500 R1500 T1500 ; sets acceleration (P, T) and retract acceleration (R), mm/sec^2 M205 X5.00 Y5.00 Z0.20 E2.50 ; sets the jerk limits, mm/sec M205 S0 T0 ; sets the minimum extruding and travel feed rate, mm/sec M107 M862.3 P "MK3SMMU2S" ; printer model check M862.1 P0.4 ; nozzle diameter check M115 U3.8.1 ; tell printer latest fw version G90 ; use absolute coordinates M83 ; extruder relative mode M104 S265 ; set extruder temp M140 S85 ; set bed temp Tx M190 S85 ; wait for bed temp M109 S265 ; wait for extruder temp G28 W ; home all without mesh bed level G80 ; mesh bed leveling

;go outside print area G1 Y-3.0 F1000.0 G1 Z0.4 F1000.0 ; select extruder Tc ; purge line G1 X55.0 F2000.0 G1 Z0.3 F1000.0 G92 E0.0 G1 X240.0 E25.0 F2200.0 M73 P0 R262 G1 Y-2.0 F1000.0 G1 X55.0 E25 F1400.0 G1 Z0.20 F1000.0 G1 X5.0 E4.0 F1000.0

M221 S95 G92 E0.0 G21 ; set units to millimeters G90 ; use absolute coordinates M83 ; use relative distances for extrusion M900 K0.12 ; Filament gcode LA 1.5 M900 K45 ; Filament gcode LA 1.0 ;BEFORE_LAYER_CHANGE G92 E0.0 ;0.2

G1 E-2.00000 F3300.00000 G1 Z0.600 F15000.000 ;AFTER_LAYER_CHANGE ;0.2 G1 X246.524 Y148.968 G1 Z0.200 G1 E2.00000 F3300.00000 M204 S1200 G1 F3600.000 G1 Z20.600 F15000.000 G1 X61.907 Y112.954 G1 Z20.000 G1 E2.00000 F3300.00000 G1 F9600.000 G1 X61.810 Y113.543 E0.00946 G1 X61.789 Y113.707 E0.00200 G1 X61.767 Y113.871 E0.00145 G1 F12000.000;_WIPE G1 X61.789 Y113.707 E-0.04327 G1 E-1.95673 F3300.00000 G1 Z20.600 F15000.000 M107 ; Filament-specific end gcode G1 X0 Y210 F7200 G1 E2 F5000 M73 P99 R0 G1 E2 F5500 G1 E2 F6000 G1 E-15.0000 F5800 G1 E-20.0000 F5500 G1 E10.0000 F3000 G1 E-10.0000 F3100 G1 E10.0000 F3150 G1 E-10.0000 F3250 G1 E10.0000 F3300

M702 C

G4 ; wait M221 S100 ; reset flow M900 K0 ; reset LA M104 S0 ; turn off temperature M140 S0 ; turn off heatbed M107 ; turn off fan ; Lift print head a bit G1 Z50.6 ; Move print head up G1 X0 Y200 F3000 ; home X axis M84 ; disable motors M73 P100 R0 ; filament used [mm] = 33605.7 ; filament used [cm3] = 80.8 ; filament used [g] = 99.4 ; filament cost = 2.9

; total filament used [g] = 99.4 ; total filament cost = 2.9 ; estimated printing time (normal mode) = 4h 22m 31s

; avoid_crossing_perimeters = 0 ; bed_custom_model = ; bed_custom_texture = ; bed_shape = 0x0,250x0,250x210,0x210 ; bed_temperature = 90 ; before_layer_gcode = ;BEFORE_LAYER_CHANGE\nG92 E0.0\n;[layer_z]\n\n ; between_objects_gcode = ; bottom_fill_pattern = rectilinear ; bottom_solid_layers = 4 ; bottom_solid_min_thickness = 0.5 ; bridge_acceleration = 1200 ; bridge_angle = 0 ; bridge_fan_speed = 50 ; bridge_flow_ratio = 0.9 ; bridge_speed = 60 ; brim_width = 0 ; clip_multipart_objects = 1 ; compatible_printers_condition_cummulative = "printer_notes=~/.PRINTER_VENDOR_PRUSA3D./ and printer_notes=~/.PRINTER_MODEL_MK3./ and nozzle_diameter[0]==0.4";"nozzle_diameter[0]!=0.6 and printer_model!=\"MK2SMM\" and printer_model!=\"MINI\" and ! (printer_notes=~/.PRINTER_VENDOR_PRUSA3D./ and printer_notes=~/.PRINTER_MODEL_MK(2.5|3)./ and single_extruder_multi_material)" ; complete_objects = 0 ; cooling = 1 ; cooling_tube_length = 20 ; cooling_tube_retraction = 40 ; default_acceleration = 2400 ; default_filament_profile = "Prusament PLA" ; default_print_profile = 0.15mm QUALITY @MK3 ; deretract_speed = 0 ; disable_fan_first_layers = 3 ; dont_support_bridges = 1 ; draft_shield = 0 ; duplicate_distance = 6 ; elefant_foot_compensation = 0.2 ; end_filament_gcode = "; Filament-specific end gcode" ; end_gcode = G1 X0 Y210 F7200\nG1 E2 F5000\nG1 E2 F5500\nG1 E2 F6000\nG1 E-15.0000 F5800\nG1 E-20.0000 F5500\nG1 E10.0000 F3000\nG1 E-10.0000 F3100\nG1 E10.0000 F3150\nG1 E-10.0000 F3250\nG1 E10.0000 F3300\n\nM702 C\n\nG4 ; wait\nM221 S100 ; reset flow\nM900 K0 ; reset LA\nM104 S0 ; turn off temperature\nM140 S0 ; turn off heatbed\nM107 ; turn off fan\n; Lift print head a bit\n{if layer_z < max_print_height}G1 Z{z_offset+min(layer_z+30, max_print_height)}{endif} ; Move print head up\nG1 X0 Y200 F3000 ; home X axis\nM84 ; disable motors ; ensure_vertical_shell_thickness = 1 ; external_perimeter_extrusion_width = 0.55 ; external_perimeter_speed = 120 ; external_perimeters_first = 0 ; extra_loading_move = -25 ; extra_perimeters = 0 ; extruder_clearance_height = 20 ; extruder_clearance_radius = 45 ; extruder_colour = "" ; extruder_offset = 0x0 ; extrusion_axis = E ; extrusion_multiplier = 0.99 ; extrusion_width = 0.55 ; fan_always_on = 1 ; fan_below_layer_time = 20 ; filament_colour = #FF8000 ; filament_cooling_final_speed = 3.4 ; filament_cooling_initial_speed = 2.2 ; filament_cooling_moves = 4 ; filament_cost = 28.69 ; filament_density = 1.23 ; filament_diameter = 1.75 ; filament_load_time = 0 ; filament_loading_speed = 28 ; filament_loading_speed_start = 3 ; filament_max_volumetric_speed = 25 ; filament_minimal_purge_on_wipe_tower = 15 ; filament_notes = "" ; filament_ramming_parameters = "120 100 6.6 6.8 7.2 7.6 7.9 8.2 8.7 9.4 9.9 10.0| 0.05 6.6 0.45 6.8 0.95 7.8 1.45 8.3 1.95 9.7 2.45 10 2.95 7.6 3.45 7.6 3.95 7.6 4.45 7.6 4.95 7.6" ; filament_settings_id = Covid19HeadbandPETG ; filament_soluble = 0 ; filament_toolchange_delay = 0 ; filament_type = PETG ; filament_unload_time = 0 ; filament_unloading_speed = 90 ; filament_unloading_speed_start = 100 ; filament_vendor = Prusa Polymers ; fill_angle = 45 ; fill_density = 100% ; fill_pattern = rectilinear ; first_layer_acceleration = 1200 ; first_layer_bed_temperature = 85 ; first_layer_extrusion_width = 0.42 ; first_layer_height = 0.2 ; first_layer_speed = 60 ; first_layer_temperature = 265 ; gap_fill_speed = 160 ; gcode_comments = 0 ; gcode_flavor = marlin ; gcode_label_objects = 0 ; high_current_on_filament_swap = 0 ; host_type = octoprint ; infill_acceleration = 2400 ; infill_every_layers = 1 ; infill_extruder = 1 ; infill_extrusion_width = 0.55 ; infill_first = 0 ; infill_only_where_needed = 0 ; infill_overlap = 27% ; infill_speed = 240 ; inherits_cummulative = "0.20mm SPEED @MK3";"Prusament PETG";"Original Prusa i3 MK3S MMU2S Single" ; interface_shells = 0 ; layer_gcode = ;AFTER_LAYER_CHANGE\n;[layer_z] ; layer_height = 0.2 ; machine_max_acceleration_e = 10000,5000 ; machine_max_acceleration_extruding = 1500,1250 ; machine_max_acceleration_retracting = 1500,1250 ; machine_max_acceleration_x = 9000,960 ; machine_max_acceleration_y = 9000,960 ; machine_max_acceleration_z = 500,1000 ; machine_max_feedrate_e = 120,120 ; machine_max_feedrate_x = 500,100 ; machine_max_feedrate_y = 500,100 ; machine_max_feedrate_z = 12,12 ; machine_max_jerk_e = 2.5,4.5 ; machine_max_jerk_x = 5,8 ; machine_max_jerk_y = 5,8 ; machine_max_jerk_z = 0.2,0.4 ; machine_min_extruding_rate = 0,0 ; machine_min_travel_rate = 0,0 ; max_fan_speed = 50 ; max_layer_height = 0.25 ; max_print_height = 210 ; max_print_speed = 300 ; max_volumetric_speed = 0 ; min_fan_speed = 30 ; min_layer_height = 0.07 ; min_print_speed = 25 ; min_skirt_length = 4 ; notes = ; nozzle_diameter = 0.4 ; only_retract_when_crossing_perimeters = 0 ; ooze_prevention = 0 ; output_filename_format = {input_filenamebase}{layerheight}mm{filamenttype[0]}{printermodel}{print_time}.gcode ; overhangs = 1 ; parking_pos_retraction = 85 ; perimeter_acceleration = 1000 ; perimeter_extruder = 1 ; perimeter_extrusion_width = 0.55 ; perimeter_speed = 160 ; perimeters = 2 ; post_process = ; print_settings_id = Covid19Headband ; printer_model = MK3SMMU2S ; printer_notes = Don't remove the following keywords! These keywords are used in the "compatible printer" condition of the print and filament profiles to link the particular print and filament profiles to this printer profile.\nPRINTER_VENDOR_PRUSA3D\nPRINTER_MODEL_MK3\n ; printer_settings_id = Covid19Headband ; printer_technology = FFF ; printer_variant = 0.4 ; printer_vendor = ; raft_layers = 0 ; remaining_times = 1 ; resolution = 0 ; retract_before_travel = 1 ; retract_before_wipe = 0% ; retract_layer_change = 1 ; retract_length = 2 ; retract_length_toolchange = 3 ; retract_lift = 0.6 ; retract_lift_above = 0 ; retract_lift_below = 209 ; retract_restart_extra = 0 ; retract_restart_extra_toolchange = 0 ; retract_speed = 55 ; seam_position = nearest ; serial_port = ; serial_speed = 250000 ; silent_mode = 0 ; single_extruder_multi_material = 0 ; single_extruder_multi_material_priming = 0 ; skirt_distance = 1 ; skirt_height = 3 ; skirts = 1 ; slice_closing_radius = 0.049 ; slowdown_below_layer_time = 10 ; small_perimeter_speed = 90 ; solid_infill_below_area = 0 ; solid_infill_every_layers = 0 ; solid_infill_extruder = 1 ; solid_infill_extrusion_width = 0.55 ; solid_infill_speed = 120 ; spiral_vase = 0 ; standby_temperature_delta = -5 ; start_filament_gcode = "M900 K{if printer_notes=~/.PRINTER_MODEL_MINI./ and nozzle_diameter[0]==0.6}0.12{elsif printer_notes=~/.PRINTER_MODEL_MINI./}0.2{elsif nozzle_diameter[0]==0.6}0.05{else}0.12{endif} ; Filament gcode LA 1.5\n{if printer_notes=~/.PRINTER_MODEL_MINI./};{elsif printer_notes=~/.PRINTER_HAS_BOWDEN./}M900 K200{elsif nozzle_diameter[0]==0.6}M900 K24{else}M900 K45{endif} ; Filament gcode LA 1.0" ; start_gcode = M862.3 P "[printer_model]" ; printer model check\nM862.1 P[nozzle_diameter] ; nozzle diameter check\nM115 U3.8.1 ; tell printer latest fw version\nG90 ; use absolute coordinates\nM83 ; extruder relative mode\nM104 S[first_layer_temperature] ; set extruder temp\nM140 S[first_layer_bed_temperature] ; set bed temp\nTx\nM190 S[first_layer_bed_temperature] ; wait for bed temp\nM109 S[first_layer_temperature] ; wait for extruder temp\nG28 W ; home all without mesh bed level\nG80 ; mesh bed leveling\n\n;go outside print area\nG1 Y-3.0 F1000.0\nG1 Z0.4 F1000.0\n; select extruder\nTc\n; purge line\nG1 X55.0 F2000.0\nG1 Z0.3 F1000.0\nG92 E0.0\nG1 X240.0 E25.0 F2200.0\nG1 Y-2.0 F1000.0\nG1 X55.0 E25 F1400.0\nG1 Z0.20 F1000.0\nG1 X5.0 E4.0 F1000.0\n\nM221 S{if layer_height<0.075}100{else}95{endif}\nG92 E0.0\n ; support_material = 1 ; support_material_angle = 0 ; support_material_auto = 1 ; support_material_buildplate_only = 1 ; support_material_contact_distance = 0.1 ; support_material_enforce_layers = 0 ; support_material_extruder = 0 ; support_material_extrusion_width = 0.35 ; support_material_interface_contact_loops = 0 ; support_material_interface_extruder = 0 ; support_material_interface_layers = 2 ; support_material_interface_spacing = 0.2 ; support_material_interface_speed = 100% ; support_material_pattern = rectilinear ; support_material_spacing = 2 ; support_material_speed = 60 ; support_material_synchronize_layers = 0 ; support_material_threshold = 55 ; support_material_with_sheath = 0 ; support_material_xy_spacing = 50% ; temperature = 265 ; thin_walls = 0 ; threads = 12 ; thumbnails = ; toolchange_gcode = ; top_fill_pattern = rectilinear ; top_infill_extrusion_width = 0.5 ; top_solid_infill_speed = 100 ; top_solid_layers = 5 ; top_solid_min_thickness = 0.6 ; travel_speed = 250 ; use_firmware_retraction = 0 ; use_relative_e_distances = 1 ; use_volumetric_e = 0 ; variable_layer_height = 1 ; wipe = 1 ; wipe_into_infill = 0 ; wipe_into_objects = 0 ; wipe_tower = 1 ; wipe_tower_bridging = 10 ; wipe_tower_no_sparse_layers = 0 ; wipe_tower_rotation_angle = 0 ; wipe_tower_width = 60 ; wipe_tower_x = 170 ; wipe_tower_y = 125 ; wiping_volumes_extruders = 70,70 ; wiping_volumes_matrix = 0 ; xy_size_compensation = 0 ; z_offset = 0

[rtyr]

@mw2matze Can you please attach your full gcode? (you might need to archive it to zip first or just change file extension)

[DRracer]

@rcaslis thanks for your report, the new FW shall definitely convert existing G-codes seamlessly (i.e. no need to reslice everything). Looking at your photo this looks like something else than LA kicking in. You can disable LA completely just by setting M900 K0. The corners might not be sharp, but you can see if it makes any difference on the straight perimeter lines.

@wavexx FYI

[FalconMuc]

Just wanted to state, that I have the same/similar issue. I updated my I3 MK3S to 3.9.0., printed one of my standards objects that I already printed many times before, with the exact same filament and the exact same gcode and the quality decrease immediately!!! I then DOWNGRADED to 3.8.1 again because I had to print in a good quality. After downgrading, I printed the object again and the quality increased immedately, BUT I can't get rid of the feeling that the print quality (surface finish,...) is not the same as before. I compared several of the prints and the quality is slightly decreased. I presented the different prints to several TEST persons and they all declared the 3.9.0 as the worst, followed by the downgraded 3.8.1 print and the best was the original 3.8.1. print. All 5 TEST persons came to the same result. Is it possible that the firmware 3.9.0 kind of changes some parameters in the printer and that the DOWNGRADING didn't change the parameters back? I was looking forward to 3.9.0. and at the moment I'm really disappointed...

[wavexx]

@FalconMuc pics and model would greatly help debugging the issue.

There's no setting which is explicitly modified in 3.9.0. Switching back to 3.8.1 should restore identical results to before.

[ptashek]

I also have this issue with my MK3 MMU2S after moving from 3.8.x (last version before 3.9) to the initial 3.9 release. The quality drop is quite terrifying to be frank. Filament used was a dry stored roll of silver Prusament PLA (roll ID: 1b675bc0).

All relevant files are in this Dropbox folder: https://www.dropbox.com/sh/5067p5agudhh7o3/AADQVEJjEJE3ZrozDfsZDPvma?dl=0

• image of the part perfectly showing the issue(s) (also below)
• STL of the model
• gCode as generated by PrusaSlicer 2.2.0 (latest available for download)
• 3MF project file saved from same PrusaSlicer

I've never seen anything like this post-update :(

[mullcom]

I have a tip for all that have issues. I did have Other issue but when I did reset of printer power it of for a while and recalibrating it my issue was away. So if you not test this it can be a good way to do.

send from mobile

Den tors 4 juni 2020 18:05Lukasz Szmit notifications@github.com skrev:

I also have this issue with my MK3 MMU2S after moving from 3.8.x (last version before 3.9) to the initial 3.9 release. The quality drop is quite terrifying to be frank. Filament used was a dry stored roll of silver Prusament PLA (roll ID: 1b675bc0).

All relevant files are in this Dropbox folder: https://www.dropbox.com/sh/5067p5agudhh7o3/AADQVEJjEJE3ZrozDfsZDPvma?dl=0

• image of the part perfectly showing the issue(s) (also below)
• STL of the model
• gCode as generated by PrusaSlicer 2.2.0 (latest available for download)
• 3MF project file saved from same PrusaSlicer

I've never seen anything like this post-update :(

[image: 3 9fw] https://user-images.githubusercontent.com/2490317/83780491-1fa52800-a685-11ea-9152-9dd913b8e52a.jpg

— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/prusa3d/Prusa-Firmware/issues/2693#issuecomment-638952442, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIJOPLS6KYS5RHRYHHQVEFDRU7A5VANCNFSM4NMOWFNA .

[rtyr]

@ptashek I tried your gcode. It was printed fine on my MK3SMMU2S with 3.9.0. Same filament.

[Kachidoki2807]

Hi, I had the same issue here. I printed a bunch of ears savers on both of my MK3s and MK3s MMU2s before the upgrade to 3.9.0. After the upgrade, the same G-Code decreased in quality. So I resliced the project, keeping my print settings but resetting the filament's and the printer's settings to take the new LA parameters. I had the exact same issue.

So I made a test by printing the same G-Code once with the normal K factor and once with K0. Below are the results on both printers. Please be so kind to not blame me or my printers with the ugly print quality, I push the machines to the extrusion limits (probably even a bit over) to get the highest yield as I print 200 of these ears savers a day.

The defect is not as visible as when I print a full plate, but still visible. It can miss up to 2 or 3mm of plastic and thus the part is not robust anymore.

Global view:

Near view with LA:

Near view without LA:

Another sample with more pronounced defect:

Generally speaking, except this defect, the quality is better with the LA enabled, especially at high speed. But the perimeter loops are not properly closed in this situation with the LA enabled. No issue when disabling it. The under/over-extrusion on straight lines is due to the extreme settings, do not take care of it.

EDIT: FYI, I also tried with Prusament to eliminate the filament from the equation.

[rtyr]

@Kachidoki2807 Have you tried to calibrate K value to reflect speeds/temperature used for these prints?

[Kachidoki2807]

Nope, I didn't looked for a better K factor since I never had issues with the default value. The point is that there is a visible change between those two versions. I could maybe try to find a better K factor just to see if it helps.

Will try that.

[wavexx]

On Fri, Jun 05 2020, Kachidoki wrote:

I could maybe try to find a better K factor just to see if it helps.

Will try that.

It would be great, thanks. Doing so will help us see if there's a mis-calculation of the new conversion factor.

[Kachidoki2807]

Ok so I am not sure of the procedure to apply, but here is what I did. First test at "normal" speed, and second test at "insane" speed. I set the other values (temp, accel, extrusion multilier and so on...) to the same I used for the print.

First:

Second:

As far as I can read the result, by looking either the acceleration or the deceleration, the best value in both cases is between 0.04 and 0.06 with a nominal at 0.05.

I have no idea on how to trap this issue, I will think about it this night.

[ptashek]

@rtyr That print looks like what I have come to expect from my MK3S over the years I had it. However, I can't get that print to any reasonable quality on 3.9. It fails in a myriad of random but similar ways to the pic I have posted - missed perimeters, extreme underextrusion etc.

Meanwhile, I have downgraded to 3.8.1, cycled power and printed the same gCode - no issues whatsoever.

From where I stand, this is clearly a firmware problem as that's the only variable in my case.

[enzyme00]

Generally speaking, except this defect, the quality is better with the LA enabled, especially at high speed. But the perimeter loops are not properly closed in this situation with the LA enabled. No issue when disabling it. The under/over-extrusion on straight lines is due to the extreme settings, do not take care of it.

I'm having the same issue with 3.9.0 using a .4mm volcano. Perimeters are not connecting correctly. Sigh.

[Kachidoki2807]

@ptashek here is the result of your G-Code printed on my MMU2S:

Maybe you should look elsewhere, it looks like an adhesion issue to me.

[DanielSan3318]

@ptashek hier ist das Ergebnis Ihres G-Codes, der auf meiner MMU2S gedruckt ist:

Vielleicht solltest du woanders suchen, es sieht für mich nach einem Haftungsproblem aus.

Sorry, I can not agree. The fact is, for whatever reason, some people have problems with FW 3.9, I am one of them, others who have the same printer, even from the 1st generation, it works. I don't know why that is, but I hope that the problem will be recognized in the near future, but with FW 3.8 the MK3S again delivers clean results.

[DanielSan3318]

OK, can be a liability problem, but the FW 3.9 is faulty for many and have tested different FW 3.9.

[DanielSan3318]

Printed here with Hilbert curve (FW 3.8.1)

[DanielSan3318]

Printed here with Hilbert curve (FW 3.9) Exactly the same G code, tested with both LA 1.0 and LA 1.5.

[mullcom]

I try to find a way to test the difference between LA1.0 and 1.5

I looked on website and forums but no explaining how to change it in the software. Please send me a picture of the setting.

send from mobile

Den lör 6 juni 2020 12:14DanielSan3318 notifications@github.com skrev:

[image: Bild 02] https://user-images.githubusercontent.com/66514433/83941816-ac1f2a00-a7ee-11ea-804a-a3911bf75791.jpg Printed here with Hilbert curve (FW 3.9) Exactly the same G code, tested with both LA 1.0 and LA 1.5.

— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/prusa3d/Prusa-Firmware/issues/2693#issuecomment-640029608, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIJOPLRXX2YW6SZFZLLOY43RVIJHBANCNFSM4NMOWFNA .

[DanielSan3318]

It's very simple, just change the K value in the G code. M900 K45 (PETG) LA 1.0 or M900 K0.12 (PETG) LA1.5

PLA M900 K30 ; LA 1.0 or M900 K0.06 ; LA1.5

ABS / ASA M900 K20 ; LA 1.0 or M900 K0.04 ; LA1.5

[DanielSan3318]

With the default setting in the slicer, both are output, simply delete an M900 K, you only need one

Here is an example with PETG and LA 1.5 M73 P0 R22 M73 Q0 S22 M201 X1000 Y1000 Z200 E5000 ; sets maximum accelerations, mm/sec^2 M203 X200 Y200 Z12 E120 ; sets maximum feedrates, mm/sec M204 P1250 R1250 T1250 ; sets acceleration (P, T) and retract acceleration (R), mm/sec^2 M205 X10.00 Y10.00 Z0.40 E4.50 ; sets the jerk limits, mm/sec M205 S0 T0 ; sets the minimum extruding and travel feed rate, mm/sec M107 M862.3 P "MK3S" ; printer model check M862.1 P0.4 ; nozzle diameter check M115 U3.9.0 ; tell printer latest fw version G90 ; use absolute coordinates M83 ; extruder relative mode M140 S80 ; set bed temp M104 S170 ; set extruder temp M190 S80 ; wait for bed temp G28 W ; home all without mesh bed level M104 S240 ; set extruder temp G80 ; mesh bed leveling M109 S240 ; wait for extruder temp G1 Y-3.0 F1000.0 ; go outside print area G92 E0.0 G1 X60.0 E9.0 F1000.0 ; intro line M73 Q0 S22 M73 P0 R22 G1 X100.0 E12.5 F1000.0 ; intro line G92 E0.0 M221 S95 G21 ; set units to millimeters G90 ; use absolute coordinates M83 ; use relative distances for extrusion M900 K0.12 ; Filament gcode LA 1.5 M221 S95 ; Flow ;BEFORE_LAYER_CHANGE G92 E0.0 ;0.2

[mullcom]

Ahaa. Thx. Now I can make some test and know which I print with.

send from mobile

Den lör 6 juni 2020 12:43DanielSan3318 notifications@github.com skrev:

It's very simple, just change the K value in the G code. M900 K45 (PETG) LA 1.0 or M900 K0.12 (PETG) LA1.5

PLA M900 K30 (PETG) LA 1.0 or M900 K0.06 (PETG) LA1.5

ABS / ASA M900 K20 (PETG) LA 1.0 or M900 K0.04 (PETG) LA1.5

— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/prusa3d/Prusa-Firmware/issues/2693#issuecomment-640036050, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIJOPLV3ES37ZBPROG5M54LRVIMT7ANCNFSM4NMOWFNA .

[Kachidoki2807]

Sorry, I can not agree. The fact is, for whatever reason, some people have problems with FW 3.9, I am one of them, others who have the same printer, even from the 1st generation, it works. I don't know why that is, but I hope that the problem will be recognized in the near future, but with FW 3.8 the MK3S again delivers clean results.

Indeed, I was misleaded on the purpose of the topic, I was too focus on the LA which should have a massive effect on acceleration / deceleration but not on straight lines. My apologies.

Maybe here it is a more global extrusion issue and maybe it is not related to the LA at all. In all cases, there is a quality regression, exactly as the topic is qualified.

When I look all the pictures here, it seems to be two separate behaviors. The first (@rcaslis and @ptashek and maybe @DanielSan3318 but not sure) is like over-extrusion or rather a "dotted" extrusion. The second (@mw2matze and mine) is like under-extrusion related to the LA. That is only an assumption based on an analysis of the pictures.

[DanielSan3318]

My parts are printed with PETG, so light threads, Hilbert curve is nicer with PLA. :-)

Perhaps to mention that I have a Bondtech extruder (E852 steps), but as I said, I have tested various FW 3.9 and also checked the values ​​with M503, just like with FW 3.8.1

So I ask the people who have a problem whether they use the original extruder (E280.00 steps with original) or another one?

[ptashek]

@Kachidoki2807 I agree that this is a wider issue than just LA, as in my case the same gCode printed with LA1.0 and LA1.5 fails to print correctly on FW3.9.

@DanielSan3318 My MK3S MMU2S is stock, however it started life as an MK3 (Sept 2018) and was later (Feb 2019) upgraded using the official parts kit.

Maybe there's a clue to the issue in specific hardware revisions of the control board?

[Kachidoki2807]

I made some more tests. Firstly, I prepared a very quick test (1min print) able to reproduce my defect. I printed several combinaisons of the LA parameter.

Freshly sliced with my insane settings (assume it must use LA1.5): M900 K0.06 ; Filament gcode LA 1.5 M900 K30 ; Filament gcode LA 1.0

Very same G-Code but with M900 K0 instead of both: M900 K0

Very same G-Code but with only LA1.0: M900 K30 ; Filament gcode LA 1.0

Freshly sliced with stock 0.20mm QUALITY settings (excepted thin wall):

Next step for me is to find out exactly which setting has such an impact, before to downgrade the firmware and repeat these tests.

[DRracer]

@Kachidoki2807 @DanielSan3318 thank you for detailed reports, from your photos it looks like we have generally two issues (FYI @wavexx ):

• with LA enabled the start of the path is missing filament (sometimes less, sometimes more) - best seen on @Kachidoki2807 's star
• short infill lines (roughly up to 5mm of length) are overextruded in some cases - probably due to some miscalculation in slowdown/acceleration. Clearly visible on @DanielSan3318 's cube.

@Kachidoki2807 could you please post your G-code for the star?

Also, please note there is only one LA algorithm in the FW - the LA1.5. If you input old LA1.0 K-factor into the G-code, they will be converted into LA1.5 K-factor, but the algorithm stays the same.

[Kachidoki2807]

please note there is only one LA algorithm in the FW - the LA1.5. If you input old LA1.0 K-factor into the G-code, they will be converted into LA1.5 K-factor, but the algorithm stays the same.

Indeed, but we're never sure of the side effects on rounding/approximation while using floats values, especially when using so small values and equality tests. At least, the test proved that there is no apparent issue here.

@Kachidoki2807 could you please post your G-code for the star?

Sure, here you go. Body1_0.25mm_PLA_MK3S_1m.gcode.zip

I had enough time to do only one more test, where I slowed down the accelerations to the default values. It was better but still present, about half less missing filament.

[3d-gussner]

@DanielSan3318 Which firmware do you have?

My parts are printed with PETG, so light threads, Hilbert curve is nicer with PLA. :-)

Perhaps to mention that I have a Bondtech extruder (E852 steps), but as I said, I have tested various FW 3.9 and also checked the values ​​with M503, just like with FW 3.8.1

So I ask the people who have a problem whether they use the original extruder (E280.00 steps with original) or another one?

With E832 you are running with 32 microsteps.

This isn't the supported configuration from Bondetech, see: https://github.com/BondtechAB/Bondtech-Prusa-Firmware/blob/Bondtech-MK3-FW390/Firmware/variants/Bondtech-MK3S-16-EINSy10a-E3Dv6full.h#L49 https://github.com/BondtechAB/Bondtech-Prusa-Firmware/blob/Bondtech-MK3-FW390/Firmware/variants/Bondtech-MK3S-16-EINSy10a-E3Dv6full.h#L216

There are know issues with E-ustep 32 and high speeds.

I know that these values work for you with FW3.8.1 but we might hit similar know issues with FW3.9.0 and Bondtech extruders.

[DanielSan3318]

Have tried and tested different FW, from original to Bondtech, but actually need the original FW, because I have no problems in height (Z), because my Z_top is adjusted accordingly. Now I have original FW 3.8.1 on it again.

[3d-gussner]

@DanielSan3318 Okay. Please keep in mind that even with FW3.8.1 and Bondtech Extruder upgrade people reported issues with E ustep 32 and E830. Do you compile your own firmware? If so what changes do you apply to your custom firmware to be able to run the Bondtech Extruder? It would be helpful if you could add a list of modifications you made to your printer.

[3d-gussner]

@rcaslis Which firmware do you use? Can you please share the M503? Also see my comments above.

[3d-gussner]

@Kachidoki2807 and everyone else interested: Can you try to print https://github.com/prusa3d/Prusa3D-Test-Objects/issues/12 and report back the results? You don't need to print it with bottom/top or infill. Please also feel free to change the seams orientation and show the different results.

@Kachidoki2807 can you share your star as 3mf file? I guess you have seams aligned or rear/back, please changes these to nearest or random to see if you get better results with the different seams settings.