(Replacement) Extruders not working

[bluemike807]

As a followup to this thread: viewtopic.php?f=19&t=18367

After speaking with Geeetech support, and purchasing two of the parts they recommended: https://www.geeetech.com/mk8-extruder-h ... -1012.html

I installed the replacement kit - but encountered a critical issue with feeding filament.

Have found this using both PET-G and PLA.

So:

- Installed new kit.
- Heated hot end to 230. Fed filament through.
- Initially flow was ok, but after a few seconds and hardly any material the head seemed to 'block up'. No more material was being pushed through and the motor sounded as if it was labouring.

- Removed the feed motor and tried to feed the filament to the still heated hot end manually. Required great pressure just to get little material through.

Obviously will not print this way. Thought it might have been a defective nozzle, so I installed the second of the two identical kits and tried it with PLA.

Exact same issue. Immediately 'gummed up' and will no longer feed filament.

Please advise on how I can fix this.

[Cup]

As a followup to this thread: viewtopic.php?f=19&t=18367

After speaking with Geeetech support, and purchasing two of the parts they recommended: https://www.geeetech.com/mk8-extruder-h ... -1012.html

I installed the replacement kit - but encountered a critical issue with feeding filament.

Have found this using both PET-G and PLA.

So:

- Installed new kit.
- Heated hot end to 230. Fed filament through.
- Initially flow was ok, but after a few seconds and hardly any material the head seemed to 'block up'. No more material was being pushed through and the motor sounded as if it was labouring.

- Removed the feed motor and tried to feed the filament to the still heated hot end manually. Required great pressure just to get little material through.

Obviously will not print this way. Thought it might have been a defective nozzle, so I installed the second of the two identical kits and tried it with PLA.

Exact same issue. Immediately 'gummed up' and will no longer feed filament.

Please advise on how I can fix this.

Hi,
First 230c is too high for PLA,190-210c is enough for it.
Then you can disassemble your hotend and check if the PTFE tubing inside your barrel(the throat tubing) was blocked.

[bluemike807]

Please note that I used both PLA and PETG and used the appropriate temperatures for both. Forgot to mention that.

And the tubing was not blocked prior to installation - I looked down the feed shaft and could see all the way out the nozzle.

[AbeFM]

My nozzle quickly gave me real issues, took it out, saw black stuff in there - while using clear material. Under microscope, after I chipped some out, it was like hard ash or something? contaminants from manufacturing, or filament, I don't know.

I nearly wrecked nozzle using super tiny drills, then just took it too garage, hit it with a pipe-welding torch till the plastic bubbled out of it, and blew in the nozzle to clear it. Doing that a couple times fixed me right up.

Remember, that's relatively dangerous stuff, have some way to put out any accidental fires, wear eye protection when blowing compressed air, etc. If you're paying attention it's easy.