Quick Manual for Anet A8 Bowden Extrusion Upgrade

Our objective is to convert popular Anet A8 direct extrusion 3D Printer to bowden extrusion with least effort. To save cost and building effort, we will re-use the some A8 parts left after disassembly of the existing X carriage and direct feed extruder.

For the new parts we will use the following kits from our store:

  • Bowden V6 Hotend for 1.75mm Filament, 0.4mm Nozzle
  • Aluminum X Carriage Upgrade Kit
  • Proximity Sensor
  • TEVO type bowden feed extruder

The following Anet A8 parts will be re-used:

  • 12 x M4x10 screws holding X carriage linear bearings in place.
  • 2 x M3x20 screws holding X belt ends.
  • 1 x 50mm blower fan.
  • 2 x M3x20 screws to hold blower fan.
  • 1 x Hotend cartridge heater.
  • 1 x  Hotend thermistor.

    Tools you will need

    • #2 cross head screwdriver 
    • 2mm Allen key
    • 1.5mm Allen key
    • Cordless drill with 1/8" drill bit

    Assembly Step 1

    Take a look at the picture below. This is correct orientation of parts before starting assembly. Make sure your heatbreak tube open end with PTFE liner faces nozzle. Make small setscrew that holds heater in places, oriented towards nozzle. 

     

    Assembly Step 2

    Screw-in the nozzle into heater block completely, then unscrew it 1/2 turn, as shown on the picture below.

     

    Assembly Step 3

    Screw-in heatbreak tube into a heater block hand tight. You don't need to apply any force at this step.

     

    Assembly Step 4

    Take your tools - 16mm open wrench or adjustable wrench, and 7mm wrench. Tighten nozzle against heater block. You are aiming at about 3 N*m of torque. Do not apply excessive torque - it can damage threads on the heater block and make it unusable.

     

    Assembly Step 5

    Using 2mm Allen key unscrew thermistor clamping screw and washer from heater block. Install thermistor glass bead into a small 2mm diameter hole. use washer and clamping screw to tighten thermistor in place. Do not overtighten or you will damage PTFE insulation on thermistor leads and make short cut between leads.

    Assembly Step 6

    Insert heater cartridge into a heater hole. Use 1.5mm Allen key to secure heater in the heater block. Finished DIY hotend is shown below. Further assembly steps will depend on your application.

     

    Firmware configuration for NTC 3950 100K Thermistor.

    Reconfigure your firmware for the NTC 100K beta value 3950K  thermistor: In configuration.h:

    • #define TEMP_SENSOR_0 11

    For safety it is strongly recommended to do the following:

    • Set the minimum temperature to detect bad wiring (HEATER_0_MINTEMP 5 in configuration.h)

    In newer versions of Marlin there are extra features for Thermal Runaway Protection should your thermistor come loose.

    Upload the new firmware to your electronics.