I have an Original Prusa i3 mk2s. I have been printing just fine for a long time. Until recently. I ran a bit of PETG through my printer (I usual just print PLA). Shortly after that, I had a clog…
Long story short, I replaced the hotend and hobbed gear and it is STILL randomly clogging (all from Prusa3d). The extruder is not clicking, it is eating into the filament. Usually I just unload, clip the end and reload. The end does not look deformed, I just clip it to get it to feed easier.
I am at a loss… I have tried 3 different brands of filament (all of which were printing fine before - standard settings) Even printing from the SD card original prints causes the jam. Did PID tuning, even though my temps are stable.
I am really stuck… Any clues?
Keith
I guess there is a bit of ballooning on the end… But IDK… I only noticed it after I took a pic… Will take a look next time.
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Maybe your extruder idler is too tight?
PETG gums up a little bit at lower temperatures. There might just be some PETG stuck at the bottom of your heat break. You might need to clean out the heat break.
I totally replaced the entire hot end…
My idler is about as loose as I can set it.
Started a marvin…missing/deleted image from Google+
What you’re experiencing is heat creep. Can you check to make sure the hotend fan is spinning unobstructed and pointed the right way?
It is. I even added an exhaust fan on the opposite side to draw more air through it.
Another test in progress… I put the original hobbed gear back in. I am thinking the new one is a tad larger, putting too much tension on the filament.
Lets see how this one goes…
Was it a preassembled hot end in both cases? If they’re not tightened to spec they can open up at temp and have internal drag inside the heater block.
It was pre assembled. I am almost convinced it was the tension on the filament. I got the treefrog print to work last night. If I can get another good print, I will say it is fixed.
It is fixed! It was too much tension on the idler. Just goes to show you, try one thing at a time. The original issue was started by the PETG. I suspect it was still in the hot end gumming it up when I tried the new hobbed gear which was a tad larger in diameter than the original.
Five good prints in a row. I am feeling confident in it again.