# Extruder clogs randomly during print

I don't know how to say this but during the print, the printer will randomly have difficulty extruding the filament. I will have to give the filament a boost for it to keep going. Once I done the boost, the extruder keeps going perfectly fine for a while.

I am using a Prusa I3 clone bought second hand. I am using the settings that the previous owner gave me (I personally know him). He previously printed a lot of stuff with those settings and they seem to work well. I also bought the brand of same filament as he did for my first roll.

My question is:

Has anyone had this problem or anything similar and if they did, how did they resolve it?

EDIT

When I say boost I mean that I have to push it down a bit more for it to countinue extruding.

I am using 3D branche filament (it's a local store in Montreal).

I do sometime hear it click before the print. When it does that. I stop the print and restart it.

• What do you define as a 'boost'? E.g. push the filament? – 0scar May 28 '18 at 14:34
• First, put in a fresh nozzle. Second, what brand & type of filament are you using? Some brands of ,e.g., PLA, have particulates which can cause jams. – Carl Witthoft May 28 '18 at 16:30
• Do you hear clicking noise? – 0scar May 28 '18 at 18:58
• @0scar added in the info int the question – Dat May 28 '18 at 19:54

Check your retraction settings. I had a similar issue and it was caused by the retraction, It retracted just about enough so the gears couldnt hit the hole properly to feed the filament into the nozzle. To fix that I lowered the value of mm on the retraction settings.

If the model you're printing is your own design, then sometimes the 3D model is itself the problem. If the printer spends a lot of time retracting (pulling back) on the filament to print things like walls with lots of gaps then the filament softens at the feed gear and nothing feeds. Slicing software should handle that use case but may not. I've had this exact problem with the Lulzbot Mini using Cura when trying to print a hydroponics netpot. I had to rethink my design after the extruder clogged.

I've adjusted the tension of the idler wheel (the bearing that pushes the filament against the extruder gear) and it seems to reduce the problem.

More thest to come.

• Hi Dat, if you have answered your own question, would you like to accept your answer (using the tick button), in order to remove the question from the unanswered list. Many thanks. – Greenonline Jul 31 '18 at 1:05
• @Greenonline, the problem still occurs from time to time, and I'm not comfortable accepting any answers yet because none of them are definitive. – Dat Aug 7 '18 at 14:56