How do you maintain the hot end temperature?



  • The hot end heater has been auto tuned.
    During a print the secondary cooling fan started at 50% speed for bridging and the hot end temperature dropped dramatically by 5 or 6 degrees.
    The print failed because the filament was not as hot as it should have been.
    Eventually over a 2-3 min period the heater recovered to the set temperature but it was too late to save the print.

    How can I improve the response time of the heater when the heater temperature is reduced by cooling?



  • Try tuning it with all fans running 100% that should solve the problem.



  • That's a good idea but before I try it, how do you think the hot end performance will be affected when the fan is not running?



  • That's what pid does it maintains the temp by lowering pwm frequency to maintain the target temp. It's also how I tuned my hotend and it works just fine 🙂

    I would suggest using the suggested max pwm from the wiki so that you get full performance from the heater.



  • Thank, I'll try that.
    The auto tune using the default 0.5 failed when I tried it before but of course I didn't have the fan on then.


  • administrators

    @appjaws:

    The hot end heater has been auto tuned.
    During a print the secondary cooling fan started at 50% speed for bridging and the hot end temperature dropped dramatically by 5 or 6 degrees.
    The print failed because the filament was not as hot as it should have been.
    Eventually over a 2-3 min period the heater recovered to the set temperature but it was too late to save the print.

    How can I improve the response time of the heater when the heater temperature is reduced by cooling?

    That's odd because with 1.15c firmware, the temperature should recover faster than it did with older firmwares, unless you were using very aggressive PID parameters. You can go back to your old PID parameters if you wish, just be sure to put the M301 command later in config.g than the M307 command, and double/halve the I and D parameters.

    How do the load change PID parameters displayed by M307 compare with the PID parameters you used to use?



  • @dc42, @Sniffle
    The old setup just used the default PID settings in the firmware.
    I hope to test this weekend and auto tune with the external fan running.

    Thanks for your help


Locked
 

Looks like your connection to Duet3D was lost, please wait while we try to reconnect.