Heated bed temperature

General LulzBot TAZ
1

Hi,

I have a LulzBot Taz 6, wasn’t new to me, and the previous owner upgraded to a heated miller aluminium bed.

However for whatever reason, I cannot get it to heat up to anything other than 110 degrees. I set it in the build in Cura, but it always changes to 110 degrees.

My Start G-Code looks like this, he kindly supplied me with this, but he mostly printed ABS, and I am starting to print with petg and PLA. its worked fine for

301 P42.07 I3.36 D131.82 ; Miller Hot end thermistor PID tuning
M304 P110.31 I20.10 D151.36 ; Miller 230v Aluminium bed modification new thermistor PID values
M75 ; start GLCD timer
G26 ; clear potential 'probe fail' condition
G21 ; set units to Millimetres
M107 ; disable fans
M420 S0 ; disable previous leveling matrix
G90 ; absolute positioning
M82 ; set extruder to absolute mode
G92 E0 ; set extruder position to 0
M140 S125.0 ; start bed heating up
M109 R185.0 ; soften filament before homing Z
G28 ; Home all axis
G1 E-5 F100 ; retract filament
M109 R170.0 ; wait for extruder to reach wiping temp
G1 X-15 Y100 F3000 ; move above wiper pad
G1 Z2 ; push nozzle into wiper
G1 X-17 Y95 F1000 ; slow wipe
G1 X-17 Y90 F1000 ; slow wipe
G1 X-17 Y85 F1000 ; slow wipe
G1 X-15 Y90 F1000 ; slow wipe
G1 X-17 Y80 F1000 ; slow wipe
G1 X-15 Y95 F1000 ; slow wipe
G1 X-17 Y75 F2000 ; fast wipe
G1 X-15 Y65 F2000 ; fast wipe
G1 X-17 Y70 F2000 ; fast wipe
G1 X-15 Y60 F2000 ; fast wipe
G1 X-17 Y55 F2000 ; fast wipe
G1 X-15 Y50 F2000 ; fast wipe
G1 X-17 Y40 F2000 ; fast wipe
G1 X-15 Y45 F2000 ; fast wipe
G1 X-17 Y35 F2000 ; fast wipe
G1 X-15 Y40 F2000 ; fast wipe
G1 X-17 Y70 F2000 ; fast wipe
G1 X-15 Y30 F2000 ; fast wipe
G1 X-17 Y35 F2000 ; fast wipe
G1 X-15 Y25 F2000 ; fast wipe
G1 X-17 Y30 F2000 ; fast wipe
G1 X-15 Y25 Z1.5 F1000 ; slow wipe
G1 X-17 Y23 F1000 ; slow wipe
G1 Z10 ; raise extruder
M109 R170.0 ; wait for extruder to reach probe temp
G1 X-9 Y-9 ; move above first probe point
M204 S100 ; set probing acceleration
G29 ; start auto-leveling sequence
M420 S1 ; activate bed level matrix
M425 Z ; use measured Z backlash for compensation
M425 Z F0 ; turn off measured Z backlash compensation. (if activated in the quality settings, this command will automatically be ignored)
M204 S500 ; restore standard acceleration
G1 X0 Y0 Z15 F5000 ; move up off last probe point
G4 S1 ; pause
M400 ; wait for moves to finish
M117 Heating... ; progress indicator message on LCD
M109 R250.0 ; wait for extruder to reach printing temp
M190 S125.0 ; wait for bed to reach printing temp
G1 Z2 E0 F75 ; prime tiny bit of filament into the nozzle
M117 Printing... ; progress indicator message on LCD

From what I can work out, M140 S125.0 is setting the bed temp, but that doesn’t seem to be inline with the 110 degrees.

2

That is a very high bed temperature and I’m not sure the TAZ 6 bed can go that high.

What filament are you printing with that recommends that high a bed temperature?

For PLA, I use a bed temperature of 60. For ABS 110. I don’t have anything more exotic than that.

3

its an aftermarket bed - an aluminium plate. I just can’t see why it goes that high no matter what it says in my print settings

4

Every temperature in your startup GCODE is hard-coded - it doesn’t matter what you set in your slicer for the bed or hot end. It’s being overridden.

That’s why it’s heating to max temp every time. It’s got a hard-coded bed temp in your startup GCODE.

Replace those lines in Cura with the placeholder values, which will dynamically change those temps based on your material profiles:

M140 S{material_bed_temperature_layer_0} ; start bed heating up
M109 R{material_soften_temperature} ; soften filament before homing Z
...
M109 R{material_wipe_temperature}   ; wait for extruder to reach wiping temp
...
M109 R{material_probe_temperature} ; wait for extruder to reach probe temp
...
M109 R{material_print_temperature_layer_0} ; wait for extruder to reach printing temp
M190 R{material_bed_temperature_layer_0} ; wait for bed to reach printing temp

The bed temp of the Taz6 is limited to 110, that’s why setting it at 125 just puts it at the 110c temperature.

1 Like
5

Thanks - I understand now, I think it threw me off because it was 125.