[Solved] Choppy / segmented extrusion.  

  RSS
rodogarcia
(@rodogarcia)
New Member

Hello all, 

I've had my MK3S for a few weeks. I have been able to print several items successfully, the last of which was a 40hr print with Galaxy Silver PLA. After the print I switched to Hatchbox Wood filament (which I have already used on this printer) and I started having the segmented extrusion issue. I can't get the printer to extrude evenly regardless of what I have tried (see image). The filament will flow for a second or two, then the nozzle pressure drops and the filament begins to curl or string. 

Things I have tried to correct the issue:

- Re-Flashed 3.9.0

- Flashed back to 3.8.1 

- Several cold pulls. Output looks good to me.

- Acupuncture needle at 215*

- First layer calibration several times, even though the issue seems to be with flow and not adhesion. 

- Checked the extruder gear screw. Screw was tight and gear was not spinning freely. Idler gear spins freely and meshes well with drive gear. Filament is centered on the grooves. I have put a small amount of tension on the filament as it enters the extruder body to see if the gears are slipping and they have not.

- Removed the hot-end and checked the PTFE tube. Tube seems undamaged and has no clogs. 

- Varied the tension screw from almost completely loose to extremely tight, makes no difference. 

- Have tried 4 different filaments and a wide range of temperatures with the same result. I have then taken the exact same rolls and have been able to print from my FlashForge, so I truly don't think it's a filament issue.

- Have tried items I have sliced with personal settings, stock settings, and items that came on the SD card with the printer (like the stock Benchy). All have the same issue. 

 

I don't have a spare nozzle to try or I would have checked that as well. Does anyone have any thoughts or advice on what the issue could be? If a new nozzle doesn't do the trick, I'm out of ideas on what else it could be. 

 

Choppy extrusion

https://photos.app.goo.gl/BvDkUJgdBLZZ7AUc6

Posted : 06/06/2020 8:15 pm
rodogarcia
(@rodogarcia)
New Member

The problem seems to be the nozzle. Not sure if it was the Galaxy Silver that permanently clogged it, or something or premature failure, but it is printing like new after installing a replacement nozzle.

Mods feel free to close the thread. 

Posted : 07/06/2020 11:56 pm
Nomad965
(@nomad965)
Trusted Member

Live Z adjustment, use a simple first layer test square 40x40x0.2 height and adjust live z till it sticks.

Prusa i3 MK2s MK2.5s Mk3 Mk3s BearPrusa Zaribo 320 - Kit Build - Rc Driver - Tweak freak...
“I know nothing about surpassing others. I only know how to outdo myself.” -Bushido-...
Posted : 08/06/2020 12:05 am
Share:

Please Login or Register