For the last few days I have had problems with my prints (PLA). If I try to manually extrude 50 mm, the filament curls up towards the nozzle and gets stuck there creating a big blob which eventually falls off and repeats all over again. I have a video of it (which I will put up somewhere if you need to see it) and I have tried with 200, 205, 210, 215 and 220 deg and they all looks pretty much the same. After the first 20 mm or so the extruder stepper starts to click. The extruded filament seems to be very thin, but I must admit that I don’t know how thin it should be; should it actually be 0.35 mm when entering into free air?
Googling seems to indicate I have a partially clogged nozzle (I have previously had a fully clogged feeder (the PEEK piece), but in that case nothing came through). Printing is obviously impossible to do.
So what is the best way (aka easiest with the Vertex setup!) to clean the nozzle?
I have read a number of suggestions:
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Take off the nozzle and use a blowtorch to clean it
Use a guitar string (or other small instrument) to clean it while hot
Try to do a cold pull (forcing filament through the nozzle while hot, turning off the heat, waiting for the hot-end to reach 80-100 deg and then pulling the filament out). Apparently this is easy with nylon but not so with PLA.
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What is your favorite method for cleaning the nozzle for PLA?
I’ve also got a clogged nozzle. It happens because when you unload the filament it leaves behind fine filament strings clogging the PTFE tube when you load the next filament. As it can’t pass through the filament remains in the nozzle are charring and making a bottleneck (the extruded filament diameter is 0.4 mm). It also happens when you’re switching from ABS to PLA : a thin coat of ABS remains on the nozzle walls.
I took off the nozzle and used a blowtorch to heat it and then used a 1.5 mm Allen wrench to clean the inner part of the nozzle and a thin electric wire to clean the tip (carefully or you could damage or widen the thin hole).
If it’s clogged with ABS you can also soak it in acetone.
I first unloaded the filament, then pulled out the PTFE tube from the push-fit tube on top of the printhead (which was very easy once you know that you can just push on the plastic part on top to get it out ;-)). I then tried cold-pulling the filament after first raising the temperature to 220 deg, pushing some filament through, letting the hotend cool to 100 deg and then trying to pull it out. That didn’t work; I could not get it out and did not want to pull too hard as I was afraid to damage the PTFE tube within the PEEk piece.
Anyways, I found my old electric guitar and removed the high E-string and pushed it though the nozzle (I also tried it the other way around, but that wasn’t possible for some reason) while at 220 deg a number of times. Worked like a charm! The filament is now coming out with no troubles, not sticking to the hotend and is nice and “thick”. I am printing again!
The filament is now coming out with no troubles, not sticking to the hotend and is nice and “thick”.