New DuetWifi Install: Why filament unloads at the end of print?

[lasakro]

I've only owned my first printer, Tevo Tarantula, for 2 months after upgrading to DuetWifi. Thanks for everyones hard work, this thing rocks!

1. In Cura I'm still specifying the Prusa i3 with flavor Reprap as I did with the MKS electronics and Marlin but never had this problem. At the end of every Cura sliced prints the head remains on the print while the heaters turn off. The extruder then runs for maybe 10 minutes retracting the filament. When it completes the cold "hotend" breaks itself free from the print and returns as it should. Below is the end code of a print where this happens. I thought it was cause by the line right after TIME_ELAPSED, G1 F1500 E4941.13188, but I commented that out in another test and the problem persisted. Any thoughts how to fix this? I've tried to switch to Slic3r but I have alot of work to do with that to get the prints Cura is providing without barly any tweeks. I'm not seeing this problem with Slic3r and no responses from UltaMaker on this.

[[language]]
 
..
....
.....
G0 X113.91 Y143.609
G0 F18000 X113.91 Y143.174
;TIME_ELAPSED:2612.914554
G1 F1500 E4941.13188
M104 S0 ;extruder heater off
M140 S0 ;heated bed heater off (if you have it)
G91 ;relative positioning
G1 E-1 F300  ;retract the filament a bit before lifting the nozzle, to release some of the pressure
G1 Z+0.5 E-5 X-20 Y-20 F9000 ;move Z up a bit and retract filament even more
G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way
G1 Y275
M84 ;steppers off
G90 ;absolute positioning
M104 S0
;End of Gcode
;SETTING_3 {"global_quality": "[general]\\nversion = 2\\nname = ABS Profile .15\
;SETTING_3 \ndefinition = prusa_i3_xl\\n\\n[metadata]\\nquality_type = low\\ntyp
;SETTING_3 e = quality_changes\\n\\n[values]\\nbottom_layers = 6\\nbrim_width = 
;SETTING_3 4\\ncool_fan_enabled = False\\ninfill_pattern = grid\\ninfill_sparse_
;SETTING_3 density = 30\\nlayer_height = 0.15\\nlayer_height_0 = 0.2\\nmaterial_
;SETTING_3 bed_temperature = 100\\nmaterial_print_temperature = 250\\nretraction
;SETTING_3 _speed = 25\\nspeed_infill = 150\\nspeed_layer_0 = 30\\nspeed_print =
;SETTING_3  150\\nspeed_topbottom = 150\\nspeed_travel = 300\\nspeed_travel_laye
;SETTING_3 r_0 = 60\\nsupport_enable = False\\nsupport_infill_rate = 10\\nsuppor
;SETTING_3 t_type = buildplate\\ntop_bottom_thickness = 0.8\\ntop_layers = 6\\nw
;SETTING_3 all_thickness = 0.8\\n\\n"}
 

[burtoogle]

Shouldn't the G91 be M83?

Gcode doc says:

Example: G91

All coordinates from now on are relative to the last position. Note: RepRapFirmware latest revision firmware uses M83 to set the extruder to relative mode: extrusion is NOT set to relative by ReprapFirmware on G91: only X,Y and Z are set to relative. By contrast, Marlin (for example) DOES also set extrusion to relative on a G91 command, as well as setting X, Y and Z.

[burtoogle]

BTW this is what I use as my end of print code with Cura:

[[language]]
M83 ; extruder relative mode
M104 S0 ; turn off extruder
M140 S0 ; turn off bed
M106 S0 ; turn off fan
G28 ; home
M84 ; disable motors
 

And the start of print code is:

[[language]]
G28 ; home all axes
G1 X0 Y0 Z25 F8000 ; descend
M82 ; extruder absolute mode
 

[dc42]

@burtoogle:

Shouldn't the G91 be M83?

Gcode doc says:

Example: G91

All coordinates from now on are relative to the last position. Note: RepRapFirmware latest revision firmware uses M83 to set the extruder to relative mode: extrusion is NOT set to relative by ReprapFirmware on G91: only X,Y and Z are set to relative. By contrast, Marlin (for example) DOES also set extrusion to relative on a G91 command, as well as setting X, Y and Z.

Yes, that's the problem. The OP needs to add M83 just after G91 in his slicer end gcode. The G91 is still needed because there is a G1 Z0.5 move as well.

[lasakro]

Great, thank you guys.