Project Dashboard Maintenance and Repairs Mini Aerostruder Hotend Replacement Workflow

1 Gather Materials

  • Aerostruder Tool Head that needs a new hot end
  • Replacement hotend assembly [KT-HE0007]
  • 2.5mm hex key
  • Some sort of tool with a small point (Pin removal tool works well:

2 Remove the heatsink fan

Using the 2.5mm hex key, loosen and remove the four fasteners that hold the fan onto the heatsink.

Location of fastenors in green
Removing the fastenors

3 Remove the blower fan and duct

Loosen and remove the four heatsink mounting screws and remove the fan duct by sliding down off the bottom of the toolhead.

Removeing the bottom two first
Removeing the blower fan and duct

4 De-pin the heater

Using the pin removal tool, carefully remove the pins for the heater.

Note: this step is only required if the hot end assembly needs to be replaced.

Third from the arrow, carefully depress the hook on the pin.
Carefully remove the two wires.

5 Disconnect the thermistor

Depress the retention tab on the connector housing and disconnect the thermistor extension. At this point, the hot end assembly can be lifted and removed.

Thermistor Disconnected

6 Remove the hotend heatsink assembly

Remove the assembly by wiggling and pulling. Loosening the idler compression screw can help. Turn clockwise to decompress the spring.

If there is still filament stuck in the hot end, you will need to wiggle the filament guide loose from it.

Removing the hotend
Remove any fillament.

7 Inspect the extruder mechanism

Inspect the bearings, hobbed shaft, idler arm, guide tube, and drive gears. Make sure that all the components are in the correct spots. Clean if necessary.

Internal Components

8 Transfer the bearing

Remove the bearing from the old heatsink and install it in the new heatsink. A spare stepper motor shaft is a good tool to remove the bearing, just push the shaft into the bearing and then wiggle and pull the bearing out.

Bearing being removed from old unit.
Bearing removal
Bearing being installed in new unit.

9 Re-assemble

Reassemble the toolhead as shown observing the following:

Take care to not pinch any wires when installing the new heatsink assemlby.

The fan duct must be installed before the two bottom fasteners can be installed.

The red ground wire goes thought the heatsink fins and on the bottom right fastener.

The fan must be up on the heatsink before the fan duct is installed so that the wires are routed correctly.

The short fastener goes in the bottom left hole.

Both heater pins go with the latch facing outwards.

The heater and thermistor wire pairs are not polarized.

For more details, see the Assembly OHAI

Tightening the top screws into the heatsink.
Installing the blower fan and duct and tightening the bottom screws.
Tightening the 4 screws on the heatsink fan duct.
Re-pinning the heater wires.
Re-connect the thermistor.
Done! Take me home