The nozzle temperature continuously fluctuates by upwards of 70-80 degrees during print startup. It will overheat to 250° then drop to the correct print temp, then drop even further during bed leveling and calibration. The G-code should be written to bring the nozzle to temperature and sustain it through the entire setup and print and only shut off heater power when the print is complete. Seems like excessively low temps during these processes is risking a clogged nozzle. Are you doing this to reduce oozing during bed leveling? Please either fix this or explain. Thanks.
I’m pretty sure this is done to prevent oozing during the bed leveling because the leveling relies on mechanical contact of nozzle and heatbed.
I don’t see a great danger of clogging the nozzle since it purges before and after the bed leveling.
So this is all intentional.
The nozzle goes to 250C when it’s flushing out the old filament (as it doesn’t know what it was, and 250C is hot enough for almost all filaments to be purged out at slow speed - obviously a compromise had to be made here).
The nozzle goes down to 140C when it’s doing its cleaning routine before bed levelling - this is to ensure the filament isn’t going to ooze out and ensure a proper calibration. It doesn’t try and extrude at this cold temperature.
Then the nozzle obviously goes back up to normal printing temperature in order to print the prime lines and calibration routine.
OK. Thank you. Fears quelled. I appreciate your feedback.
Thank you. Good to know.