Cleaning my extruder

[luvthisprintrdrew]

After almost two years of use I faced the inevitable the other day.
Cleaning the extruder of my printrbot simple metal after two years of operation.
This one was very, very clogged. From the nozzle to the feed motor.

I watched a few youtube videos and sort of made a composite of various methods.

Tools I used and abused:
a clean old cotton sock
a large paper clip
a sewing needle smaller than .4mm
Q-Tips
Dill's pipe cleaners
a soft iron wire coat hanger
Bull nosed cutting pliers
a 12mm box end wrench
pliers, needle nose and adjustable clamp style
A hex key index
Acetone, hardware grade.
a Bic lighter
A plastic pill bottle, 250ml capacity.
A pushpin.

Important safety tips!

0) Never use acetone near an open flame.
Acetone is highly flammable.

1) When pushing a coat hanger through anything,
do it slowly. Don't stab your thumb.

2) When heating metal objects with a bic lighter,
use needle nosed pliers to hold hot metal objects.

3) When all else fails, use common sense, like adequate ventilation.
</safety tips>

Dis-assembly of the extruder:

Using the hex key, remove the right side bolt from the feeding
mechanism. It locks the heat end.

There are two black and two clear wires on this unit. Disconnect
the wire couplings and note which wire coupling fits the black and clear
wires and unplug them.

Remove the entire hot end assembly.

The red thermal jacket can be removed carefully.

Use the 12mm box end to grab the midway bolt of the extruder assembly
and use clamp style pliers to remove the brass extruder nozzle, counter clockwise.

Soak the brass extruder nozzle in a small amount of acetone placed in the pill bottle for about
30 minutes.

Unmount the plastic guide cylinder by turning counter clockwise, holding the center nut with the 12mm
box end wrench and the guide cylinder by the clamp style pliers.

Cut a length of coat hanger wire using the bull nosed wire cutters greater than the
length of the plastic guide. this can be used to push stuck filament through the plastic guide.

Untwist and straighten the large paper clip using the pliers. This wire can be used to unclog the brass feeder bolt.
Once the brass feeder bolt has been cleared, dip the pipe cleaner in acetone and clean the inside.

While the extruder tip has been soaked in acetone, the PLA residue softens.

The wire coat hanger can be used to push stuck filament out of the plastic guide cylinder.
Use acetone to wet the q-tips and clean the mounting screws of the guide cylinder.
Use acetone soaked pipe cleaners to clear out the residue of the guide cylinder.

Use the cotton sock soaked in acetone to clear away the melted PLA on the exterior of the
extruder nozzle. Use an acetone coated q-tip to clean the interior. of the extruder nozzle.
One can also use the acetone soaked sock to clean the push rods made of either wire coat hangers
or sewing needles.

The push pins can be used to clear out end points for every component.
Pipe cleaners soaked in acetone and q-tips soaked in acetone can be used to
clean everything except the brass extruder nozzle.

Once every assembly has been cleaned and scrubbed, and all flammables have been put away,
heat the sewing needle with the cigarette lighter and push it through the brass extruder nozzle.

I suspect this will re-prime the brass extruder nozzle.

Reassemble the hot end and install it into the printrbot simple metal.
Re-calibrate for the z axis.

I ran a primary test this evening and everything seemed to go well.
So far so good.

I found the calibration module for Cura this evening.
Thank you all for this much help.

You are all amazing.

I really, really love this printer Drew.

If you have any questions, let me know. I will be happy to expand on this topic.

[Mooselake]

Nice directions!

A couple small things to consider. You should remove the nozzle with the hot end at operating temperature since plastic can seep into the threads and glue the nozzle on.

Acetone will remove any oil or similar, and will dissolve ABS, but not PLA.

Kirk