Lulzbot Mini Ninjaflex

As of 2017.02.10 the Lulzbot Mini has been repaired and has a brand new extruder head. This extruder head uses NinjaFlex (TM) rubber filament only!

Cura users:

1. Download the newest version of the Lulzbot Edition of Cura from https://www.lulzbot.com/cura 2. Install and start Cura 3. From the menus: Machine -> Add New machine -> Lulzbot Mini 4. From the menus: Machine -> Machine Settings 5. Change Tool Head -> Flexystruder v2 6. E-steps per 1mm filament -> 918 7. OK 8. For your print material, choose NinjaFlex

The recommendation is 220 C for the melting temperature of the material, and it is currently advisable to lay down some glue.

Full Flexystruder head installation and initial setup instructions at https://ohai.lulzbot.com/project/flexystruder-install-lulzbot-mini/accessories/ but unless something goes horribly wrong, you should not need to mess with these instructions.

The official word on clearing jams / clogs, which helped the FIRST time it jammed, but not the second:

So if you have done cold pulls on a normal extruder its the same concept for the flexystruder. Heat up the tool head to printing temp. (well say 230) Then manually extrude some filament through the hotend by manually turning the large gear on the toolhead counter clockwise. Once you get a little string of filament coming out drop the temp of the toolhead by 100 degrees while slowly extruding a little more filament. Then once the tool head gets to the lower temp (say 130) manually retract the filament by rotating the large gear clockwise while pulling up on the filament with your hand. Try this 4-5 times and see what happens. Let us know if it works.

And, even more horribly wrong instructions: https://ohai.lulzbot.com/project/flexystruder_assembly/

About that ...

On 2020.01.20 once again, I attempted the afore-mentioned cold pull with more success: I attribute the success to using slightly more force and a lot less speed (and a lot more patience) when manually rotating the large gear in either direction.

Self-reporting

Upon connecting, the Lulzbot Mini reported:

$ pronsole.py
Welcome to the printer console! Type "help" for a list of available commands.
offline> connect /dev/ttyACM0
start
Printer is now online
Marlin 1.1.5
Last Updated: Jan 22 201809:13:46 | Author: (Aleph Objects Inc., LulzBot Git Repository)
Compiled: Jan 22 2018
Free Memory: 5336  PlannerBufferBytes: 1232
V40 stored settings retrieved (498 bytes; crc 4399)
G21    ; Units in mm
Filament settings: Disabled
M200 D3.00
M200 D0
Steps per unit:
M92 X100.50 Y100.50 Z1600.00 E833.00
Maximum feedrates (units/s):
M203 X300.00 Y300.00 Z8.00 E40.00
Maximum Acceleration (units/s2):
M201 X9000 Y9000 Z100 E1000
Acceleration (units/s2): P<print_accel> R<retract_accel> T<travel_accel>
M204 P2000.00 R3000.00 T2000.00
Advanced: S<min_feedrate> T<min_travel_feedrate> B<min_segment_time_ms> X<max_xy_jerk> Z<max_z_jerk> E<max_e_jerk>
M205 S0.00 T0.00 B20000 X12.00 Y12.00 Z0.40 E10.00
Home offset:
M206 X0.00 Y0.00 Z0.00
Auto Bed Leveling:
M420 S0
PID settings:
M301 P28.79 I1.91 D108.51
M304 P294.00 I65.00 D382.00
Z-Probe Offset (mm):
M851 Z-1.38
Stepper motor currents:
M907 X1300 Z1630 E1250
ttyACM0 PC>

Important tidbits from the official Lulzbot keychain trinket G-Code:

;This Gcode has been generated specifically for the LulzBot Mini
;Basic settings: Layer height: 0.25 Walls: 1.2 Fill: 20
;Filament Diameter: 2.9
;Nozzle Size: 0.6
...
M140 S40     ; get bed heating up
...
M109 R230    ; set extruder temp and wait

So, set bed temperature to 40° C, and hot end temperature to 230° C.