Bed Heater Tuning

When to Calibrate the Bed Heater

You should recalibrate the bed heater

• if you have just built a Jubilee
• if you replaced the silicone heated pad
• if you replaced the thermistor

Warning

If you are tuning a freshly wired Jubilee bed, be sure that you have wired it correctly, uploaded the config files, and confirmed that the bed temperature sensor is sensing a believable measurement.

Steps

Open Jubilee’s web page and navigate to the GCode Console. Ensure that your bed temperature sensor is plugged in and is reading believable results. If the bed is hot, wait for it to cool to an ambient temperature. Then enter:

M303 H0 S100

to start an auto-tuning procedure. (Note, if you changed the heater index in your config file, your heater might be H1, H2, etc.)

This procedure takes about 15-20 minutes and ramps the bed up to 100C and then back down to near-ambient temperature. Do not walk away from the printer at this time. Also, be warned that exceeding 130C will permanently damage the magnets in the magnetic build plate. When the procedure is done, the console will report back with a message describing the heater parameters and listing any warnings.

When the machine is done calibrating, enter

M500

to save the tuning results to the config-override.g file on the SD card. (Note: M500 does not work currently (4/20/2020) with Duet3 6HC boards that are paired with the PI. You will need to manually enter the tuning values from the console output into your config.g file)

References

• Duet Bed Heater Tuning Guidelines