Unclogging a 3D print head is not always an easy task, especially when you lack of the proper tools. They are sometimes hard to find.

To unclog a .35mm J-Head fitted for 1.75 mm filament, I am using a strand of a steel cable and a stake flag. The steel cable strand is small and stiff enough to be inserted in the print head by the tip of it. Its diameter is less than .35 mm. The stake flag provides me a rod that I insert in the filament intake. It is stiff and long enough to push it down to the tip of the print head. Home Depot sells both for less than 4 dollars.


The procedure to unclog the print head is:

  • heat the print head to the extrusion temperature of the filament
  • remove the filament by reverse extruding it or pulling on it
  • push the filament left in the head using the stake flag. ┬áRemove the stake flag and remove any filament that sticked to it. ┬áRepeat this a few times.
  • if the plastic does not go out from the head in a steady flow or the flow is tinier than usual, insert the steel cable strand in the tip of the J-Head and gently pull. Repeat this a few times.
  • if the tip of the head is very dirty, gently rub it with a 400 sand paper (very very fine).

That’s it!