InfimechTx Extruder Filament Sensor

Designed and created a filament sensor that sits on top of the InfimechTx's extruder. I was tired of reaching around the back to manually feed filament through the stock sensor. Moving the sensor to the extruder allows easier access and feeding. Also if you are planning on creating one of the many color changers, having a sensor as close as possible to the extruder is recommended.

Please read though everything before installing

Printing:

Please only print in ABS/ASA, do not use PLA as it will not hold up to high temperatures for ABS/ASA printing.

Make sure to add supports model to your slicer.

Slicer will probably complain about floating geometry, its ok just continue to print. 

Print Settings:

ToolHeadSensor.stl

• 0.2mm layer height
• Inner/Outer/Inner wall print order
• 4 walls
• 4 top layers
• 4 bottom layers
• 0.8 top shell thickness
• 30% infill
• Cross hatch infill
• No Brim

ToolHeadSensor_supports.stl - Setup different settings to take less filament

• 2 walls
• 3 top layers
• 2 bottom layers
• 0.4 top shell thickness
• 5% infill
• Cross hatch infill
• No brim

Hardware Needed: 

Removing Supports:

Once part is printed remove supports, you should be table to take a small screwdriver and pop the supports. Be very careful around the center hole that hold the bowden tube. See picture below.

Careful with tube and take a pair of pliers, this snaps off around where the red line is at

Fully cleaned up model should look like the following

Assembly:

• Insert ECAS04 into top, this is a tight fit and may need pliers, just be careful with bowden tube holder
• Insert magnet into square hole left of the bowden tube holder
• Insert 5mm ball bearing on the right side of the bowden tube holder, it should snap into the recessed hole.
• Insert microswitch with wires solder to C and NC pins. Make sure wire is long enough to make it though cable bundle back to the original filament sensor plug.
• Insert 9.6mm bowden tube into extruded bowden extrusion

Assembled part

Installing onto extruder:

• Remove the following 4 screws from extruder to remove black plastic bowden tube holder

• After removing black plastic bowden holder install bottom 2 screws. Make sure bottom right screw grabs and tightens the motor.  Note: Bottom right and top left both hold the motor on.
• Remove back right screw

• Put Front top and back screws somewhere safe, these will not be reused

• Install assembled filament sensor on top, it should just snap in with little effort. Make sure bowden tube seats correctly into the extruder. If you are not careful you could kink the end of the tube. If this happens it might be easier to insert the bowden tube into the extruder first then put filament sensor part on the extruder.
• Install 35mm screw in top left hole
• Install 12mm screw in top right hole
• Install 30mm screw in back hole
• Connect stock bowden tube to ECAS connector
• Route microswitch wire though braided wire sleeving. Tip: using filament as a fish tape though the sleeving for the wire works wonders.
• Solder the other end of the wire to the 3 pin JST like the following:
• If you haven't already disconnect the stock filament sensor connector and connect the 3 pin connector from the toolhead to the female plug.

Testing filament sensor

Suggest testing sensor before fully installing sensor on extruder

• Navigate to klipper web interface, then select the tune tab
• Without filament in the sensor fila_sensor should show and orange exclamation mark noting that there is no filament in the sensor
• Stick filament into the sensor to make sure it senses it and turns green.

Be sure to rerun SHAPER_CALIBRATE

You have reached the end, hopefully everything works correctly for you. Happy printing!!