I’ve got a regular thing where a freak nozzle works fine and gradually gets clogged up. Here are a couple that i replaced once the prints started failing.
In other news, I put 7 clogged nozzles in a small jar and covered them with methylene chloride and it’s cleaning them out rather well. Later today I’ll start pulling them out and trying to clear them with my needle set.
Does anyone have suggestions or a link to troubleshooting information for this issue?
Thanks
The most common cause appears to be small bits of filament getting ground away by the extruder gear teeth and slowly collecting in the nozzle.
As far as a fix, maybe do cold pulls often? @WilliamBosacker had a suggestion involving unlatching the door and holding it closed with tape to control tension.
@Artezio DCM (alternatively MC) is an organic solvent that PLA is soluble in. Smells sweet and may give you cancer. Overall, 11/10 fingers. 
. I use it for PLA vapor smoothing, similar to acetone with ABS. Requires knowledge to work with safely, and will dissolve most types of gloves including nitrile.
I’m not a chemist, what is methylene chloride?
@brent113 ohhhh “PLA printing won’t give you cancer so let’s use something that does!!”
It’s a solvent. Use lots of ventilation.
It’s in some liquid plastic model glues, though I got a pint can from Walmart by mail. Eats PLA rather quickly, but avoid getting it on the sticker. After how ethel acetate crazed mine when I was trying to get PLA off it, I tend to be wary.
I use a flat ¼" paintbrush after I’ve sanded the model to smooth the finish.
I try to keep it all clean, though I don’t take any steps to dust off the spool that sits on top of the enclosure.
It looks like the spaghetti on 20ga wire, and my I’ve wondered if it is too cool on the outside of the nozzle/in the enclosure.
I got a Govee Hygrometer Thermometer to monitor the temp and humidity in the enclosure.
Can opening the enclosure door have an effect?
The material setting is 210 degrees, which falls well within 190-220 temp recommendation for PLA, which is pretty typical.
This plugging eventually happens with every nozzle, using the same filament, so I doubt it’s a contaminate. That’s why I’ll look at temp inside the enclosure.
Is your head the original or the upgraded?
I’ll take that back, in examining previous pictures, I was seeing this happen on each of the three different spools I’ve used. I was getting it when I was using the fast print and straight PLA settings. The settings I use now let the filament stick to the bed (and I’ve tried a few different ways.) The 210C temperature is within Amolen, Matterhackers, Polymakers, Tecbears, Makerbot and PRUSA’s specifications for printing.
If you search this forum for the word ‘clog’, there are a number of posts that talk about the very same thing.
Is there someone in this forum who has printed more than 20 models - each taking more than 5 hours - on the Snapmaker 2, using the same hot end/nozzle for all models?
I am still using the same two hot ends and nozzles that came with the machine in December 2020. I have used both but neither has ever clogged. I have another printer and been using the same nozzle on that one for what must be over a year. I print PLA at 190c max, sometimes 185c, PETG hotter obviously. I also don’t print as slow as the Snapmaker recommendations, especially those in Luban. I think they are too slow. The stuff I print is for parts and prototyping though not works of art so I seldom print very fine.
I think people have problems because of printing too slow with very fine layer height and hot so the filament cooks in the nozzle as in 1 from @WilliamBosacker
