Extruder clicking mystery
First, I've been printing with 6 MK3S+ printers for over 3yrs now so I'm not new to some of the issues that can come up with them. However, I am having a persistent extruder clicking issue with 3 of the printers that I just can't figure out.
The issue is that I keep getting the clicking noise, sometimes, but not always, accompanied by a nozzle jam. I print with PETG exclusively. So it typically goes like this:
With a new nozzle I'll print perhaps 500hrs over 30 days and then the clicking sound will start.
I first try a cold pull and that rarely helps, but sometimes.
So I'll replace the nozzle (sometimes the heat break too) and all is well for another 500hrs or so and it starts again. Wash, rinse, repeat.
I have tried experimenting with different nozzle temps and any other tricks I could find but this issue is remarkably consistent and I haven't been able to figure it out. This has been happening on 3 of my printers, but not the others.
I first started to notice this pattern after I switched to using the Satin steel sheet on all my printers. Would having the nozzle too close to the bed cause these jams? I have carefully adjusted the first layer so that the print sticks well but is as high off the bed as possible.
If anyone has any advice I'm all ears.
RE: Extruder clicking mystery
Are your printers all stock? I recently upgraded a few of my printers to bondtech bmg extruders with mosquito hotends. On one of the printers I have experienced what sounds like the same issue as you... I was printing with a new filament that i've not used and I could not for the life of me pull the filament out of the top, no matter the temperature I set the hotend to. It ended up breaking right below the gears that push the filament into the hotend. I ended up swapping out the heat break for a new one. There was a bit of filament stuck between just above the ptfe tube and below the gears that was also difficult to remove. It's been printing fine now, but am very interested in what others have to say about this. I've been setting my first layer using this model: https://www.printables.com/model/360303-auto-incrementing-first-layer-calibration.