ChrisPrefect

I did some tests with bed leveling before, during and after I heated the bed and nozzle and the differences where inside the margin of error that the bltouch produces even when I do two measurements right after each other when the bed is cold. I have a glass bed, I think the thermal expansion coefficient of glass is fairly small. I did a calculation: A glass bed of 5mm thickness would expand to 5.0012mm when heated from 20C to 60C 😎

It works perfectly! Thanks a lot! 😄 The printer used 249 Watts while heating the bed, nozzle and doing the bed leveling at the same time. Bed leveling with the BLTouch and 9 points is finished before the nozzle has heated up completely, so I don't loose any time for bed leveling anymore. This is my whole start gcode for reference: M140 S{material_bed_temperature} ; start preheating the bed WITHOUT wait to what is set in Cura M104 S{material_print_temperature} T0 ; start preheating hotend WITHOUT wait to what is set in Cura M280 P0 S160 ; BLTouch alarm release G4 P100 ; delay for BLTouch G28 ; home G29 ; auto bed leveling M190 S{material_bed_temperature} ; start heating the bed to what is set in Cura and WAIT M109 S{material_print_temperature} T0 ; start heating hotend to what is set in Cura and WAIT G92 E0 ; Reset Extruder ; M92 E97 ; esteps hard set G1 Z2.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed G1 X0.1 Y20 Z0.3 F5000.0 ; Move to start position G1 X0.1 Y200.0 Z0.3 F1500.0 E15 ; Draw the first line G1 X0.4 Y200.0 Z0.3 F5000.0 ; Move to side a little G1 X0.4 Y20 Z0.3 F1500.0 E30 ; Draw the second line G92 E0 ; Reset Extruder G1 E-2 F1800 ;retract 2mm at 30mm/s G1 Z2.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed G1 E1.8 F1800 ;retract 2mm at 30mm/s

Ah! Those are variables! OK makes much more sense! Then the exact required temperatures are set automatically. OK I will have to add "M109 S{material_print_temperature}" at the end so the printer waits to actually reach the temperature if it takes longer than the bed leveling requires. I will try. Thanks a lot!

Oh now I get it. OK but even if I add "{material_print_temperature}", will cura still set the temperatures for the initial layer and the following layers etc? So this should be in my start gcode section: {material_print_temperature} {material_bed_temperature} M140 S60 ; start heating the bed to 60 degrees Celsius M104 S200 T0 ; start heating T0 to 200 degrees Celsius M280 P0 S160 ; BLTouch alarm release G4 P100 ; delay for BLTouch G28 ; home G29 ; auto bed leveling And then Cura continues to heat to the set temperatures in the slicer, for example 215 degrees?

OK nice! I tried it with this start gcode but it does not work. Cura first heats the bed, then the nozzle and then executes this code, overwriting the temperatures set in the slicer settings. It should be the other way around. Cura should set the temperatures from the slicer settings after the start gcode was executed. M140 S60 ; start heating the bed to 60 degrees Celsius M104 S200 T0 ; start heating T0 to 200 degrees Celsius M280 P0 S160 ; BLTouch alarm release G4 P100 ; delay for BLTouch G28 ; home G29 ; auto bed leveling Does Cura only look for the code M109 or should M104 also work?

It's for an Ender 3 with 24V power supply. There is more than enough power. I frequently manually heat up the bed and nozzle at the same time. Ideally the nozzle and bed would heat up at the same time and as soon as the nozzle reaches 185 degrees it would retract 20mm. And the Bed-Leveling would start immediately while heating the bed and nozzle. How can I set this up? Why does Cura execute "hidden" gcode before the manually entered gcode in the start section? Can I override this in a settings file from Cura or something? Thanks!

Hi! I tried to add some gcode to the start gcode section in cura, but apparently that code only gets executed well after the bed and the extruder has reached it's temperatures. I want to start heating the bed and the extruder at the same time, without waiting for one to reach it's temperature. There is enough power in the power supply to do so. And I want to simultaneously start leveling the bed with the BLTouch sensor. These three gcodes can run at the same time. Why can't I set that in the start gcode section? Thanks!