extrusion jam before the heated head (photos)

General LulzBot TAZ
1

Hi, (sorry for english, i’m french)

I have a pb with my extruder : I have often jam between the extruder part & the heated head.

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My both fans (filament one + head one) are working.
the screws holding the nozzle are hard tighten
I use PLA at 205°c
no other pb… it prints very well until the jam.

The extruder part seems not to have any pb. :frowning:
each time it’s stuck I have to remove all to access to the filament (it’s impossible to load or unload it.)
Thx :slight_smile:

2

That could be heat creep. The heat from the hotend works its way up into the heatsink and softens the filament. PLA seems to be the most prone to it, but it can happen with other types as well. I used this upgraded fan duct for the heatsink, it helps with that sort of issue.

http://www.thingiverse.com/thing:1461335

The look of the filament makes me wonder if you don’t also have an alignment problem. Is the filament path nice and straight?

3

Well as your picture shows a Buda hot end, you will want a different fan model. Also try a high temp cooking oil on the filament every so often as the PTFE tube builds up PLA and will cause sticking in the tube down into the hot end fully.

4

Thank you :wink:

I will try oil. Wait and see !
But :

The look of the filament makes me wonder if you don’t also have an alignment problem. Is the filament path nice and straight?

It’s nice but maybe not perfectly straight : but how do you align it perfectly ? I can’t move it and the 3D printed part of the extruder is the lulzbot original one, which seems good.