TAZ5 unwanted retraction - confused?

General LulzBot TAZ
1

Been having issues with prints sticking to the plate because when it starts, nothing is extruding. I’ve pretty much fixed it by increasing the amount of skirt that prints.

But when printing with a raft, a good portion of the raft doesnt print, because theres no primer skirt.

So, had an idea - my old makerbot would start from X/Y 0/0 and draw a nice fat line on the plate to prime the print. Using the start/end gcode tab in Cura, I added a part that made a nice fat line from x0 y0 to x100 y0, then draw 2mm to x100 y2, then back again to x0 y2.

Problem is, it went fine from x0 to x100, but as soon as it made the turn to go to x100 y2, it retracted, a lot. It never un-retracted. The extruder moved forward but nothing came out ujntil the last 15mm or so.

I then checked the code and retraction should not have been on there. I even did some googling, and used M209 to turn the auto/firmware retraction OFF. Still did it.

Here’s my start code. Why the heck is it retracting on the move to X100 Y2?

;Sliced at: {day} {date} {time}
;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}
;Print time: {print_time}
;Filament used: {filament_amount}m {filament_weight}g
;Filament cost: {filament_cost}
;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line
;M109 S{print_temperature} ;Uncomment to add your own temperature line
G21                     ;metric values
G90                     ;absolute positioning
M82                     ;set extruder to absolute mode
M107                    ;start with the fan off
G28 X0 Y0               ;move X/Y to min endstops
G28 Z0        
M209 S0          ; this should turn off firmware retraction, yes?
G0 F10500 X0.000 Y0.000 Z0.10 ; Move down
G1 F1500 X100.0 Y0 E4.0 ; draw a line to x100 y0
G1 X100.00 Y2.0 E0.08 ; draw a line to x100 y2 - retraction happens before this starts moving
G1 X0.0 Y2.0 E4.0 ; draw a line back, then finish standard Cura start code
G1 Z5.0 F{travel_speed};move the platform down 15mm
G92 E0                  ; zero the extruded length
;G1 F200 E0              ; extrude 3mm of feed stock
;G92 E0                  ; zero the extruded length again
G1 F{travel_speed}      ; set travel speed
M203 X192 Y208 Z3       ; speed limits
M209 S1
M117 Printing...        ; send message to LCD
2

E values are added so .8 then 4 is 4.8

The move where it retracts is because it is going back to .8 when it should acyualy say 5.6 or so

3

OOOHHHHHH… thank you! I didn’t realize they were added. I read some gcode from a print but wasn’t aware/didnt notice the number was always increasing.

4

if that is part of your start gcode, you should probably also reset the e values before starting the print.

5

Since they are doing absolute positioning, it extruded to 4 MM then to .08 MM then to 4 MM again. ???