How to Replace the Hot End

Replacing the full Hot End assembly of a SAAM 3D printer may need to be done periodically. The nozzles eventually wear out due to buildup or may fail completely.

Tools

  • 4mm hex wrench
  • Needle nose or small pliers

Additional Tools May Be Needed

  • Scissors or snippers to cut filament
  • 2mm hex wrench
  • 3mm hex wrench

Procedure

  1. Remove top panel

  1. From the CI Print Software interface, heat up the nozzle and retract the filament until it is no longer engaged with the extruder.

  2. Turn off nozzle heater. Wait until the Tool temperature indicator is less than 40C to avoid burn hazards. This will take approximately 15 minutes.

  3. Remove blower duct

  4. Remove 4mm hex screw from underneath extruder plate. This screw is located behind the nozzle.

  5. Move extruder to the side. You do not need to disconnect the wire as shown. It's disconnected here to exaggerate extruder movement.

NOTE:

If you were unable to remove the filament with an unjam routine, then you will need to remove the filament in this step.

  1. Cut the filament above the extruder
  2. Pull the extruder up (the filament will come out the bottom). There will be some resistance when pulling on the extruder. This is because the filament is still grabbed by the extruder hob wheels. You can safely pull up against this resistance and the filament should slide out the bottom of the extruder.

  3. Disconnect the hot-end wire bundle from the extruder cable harness (directly above extruder)

  4. Remove Hot End and replace with a new one. Ensure the hot end is fully seated against the edge of the slot

  1. Put extruder back in place

  2. Fasten extruder to extruder plate

    1. Start 4mm hex screw IMPORTANT: do not tighten the screw all the way until the hot end is all the way back
    2. Push hot end into place (as far back as it will go)
    3. Tighten hex screw

  3. Reassemble printer:

    1. Replace blower duct
    2. Replace front cover
    3. Turn on printer
    4. Start unjam routine, refeed filament when prompted and finish routine
    5. Replace top cover