Dual extruder setup in Marlin

  • I have a Tevo Tarantula with a MKS Base 1.5 board and dual extruders. I am running Marlin RC8 Tevo Community build for the dual extruder, large bed and SN04 sensor.

    All temperature sensors work and give accurate reading but E1 when activated runs at 100% until the overtemps kicks in and shuts down the system. Like I said, it reads proper temperatures through the thermistor it just won’t stop at the set temperature. I checked the MOSFET and there is no obvious scorching or bad solder joints on the MKS board. This leads me to believe it is a mix-up in firmware but, being a bit of a newbie on this, I am still getting familiar with G-code and Marlin.

    I have confirmed the correct board is being referenced in firmware from boards.h but looking at configuration.h I just get confused. What I am thinking is somehow/somewhere E1 might be referenced as a fan that is just off or on. Anybody have ideas?

    Is this build what you are using?

  • I am not sure what the hardware config is for the Tevo Tarantula

    Make sure your configuration.h file is setup for your hardware.
    The extruder defines are describe in Conditional_LCD.h

    It looks like the configuration.h file on GitHub is configured for a single extruder.

    For example, if you have 2 hotends; but, "HOTENDS=2" is not set then the I/O will not be configured for the 2nd hotend. I just looked at the code and if HOTENDS == 1 then the MOSFET_D_PIN will be used to control FAN1 (which sounds very similar to what you are describing that you are seeing).

      #if HOTENDS == 1
    #define FAN1_PIN MOSFET_D_PIN

    If the tarantula uses a single hotend, don't define SINGLENOZZLE but define SWITCHING_EXTRUDER and (i think) EXTRUDERS=2. Then the code will expect the single hotend to be connected to D10.

    Thank you for the direction to go. The setup is dual and I "thought" I had checked that.

    "Dual" can mean several things. Do you have two separate extruders (hotends), a (single) mixing extruder, or a (single) standard extruder with a dual filament feeder? Marlin has to be configured for the specific type.

  • So, following on from Mark's answer, in line 298 of Conditional_LCD.h, you would need to change:

    #define HOTENDS       1


    #define HOTENDS       2

  • I had a similar problem, my documentation was wrong and the heater & thermistor were wired in backwards. Maybe recheck your wiring and even try reversing the temp sensor on your board.

    Do you mean that you swapped the heater and thermistor connections, or do you mean that the thermistor was connected to the right therminals - but backwards? Thermistors and heaters are generally not polarized, and can be connected either way around. They're just simple resistors.

License under CC-BY-SA with attribution

Content dated before 7/24/2021 11:53 AM

Tags used