Is this heat creep? (TAZ 5)

Hey all,
In the last couple days, I’ve been experiencing a new problem with my TAZ 5 which I’ve never had before: a totally hopeless clog that requires me to take apart the extruder. The first happened just after I finished a print, removed the prior filament, and inserted new filament (both PLA—Atomic Filament and Matterhackers Pro PLA) to begin a new one. But the newly inserted filament apparently immediately got jammed, not moving forwards or backwards. I also could not remove it by unlatching the idler and pulling it out; it was so stuck, I ended up lifting the entire printer trying to remove it—and I think that may be why part of the extruder body is now cracked, so that’s also cool. :confused: I removed the nozzle, which was empty. There also was nothing in the heater block. There was filament stuck in the heat sink and a “plug” just at the beginning of it. First clog: I couldn’t get all the filament out, but once I removed the plug, I was able to reinstall the extruder assembly, heat it up to temperature, and put some cleaning filament through to clear it out. I then completed two (relatively short—about 3-4 hours) prints in PLA, though the space between the heat sink and heat block leaked a bit. (I think I successfully tightened it up, subsequently.)

The next clog I observed today after waking up to a failed print. Also PLA (Push Plastic… I have had no end of troubles getting this to print well on another TAZ, too :frowning:), also nothing blocking the nozzle or the heater block, but the heat sink is stuffed right up. The filament going into the heat sink looks swollen, and I’m at a loss as to how to safely remove it without borking everything. Here’s the picture: The failed print had a lot of extremely underextruded layers, interspersed throughout with increasing frequency, until it finally failed. Here’s a picture of a piece of the print which might help diagnose the issue (it broke apart when removing it from the bed): IF this is heat creep, I don’t know if it caused the print to fail or merely happened later, because it kept “printing” while not moving the filament through.

So I think I probably need to put a beefier fan on there to cool the heat sink? Is there a temporary solution, like just pointing a big, honking fan at the whole print in the meantime? But most importantly, how can I get the rest of that PLA clog out? Would a hair drier get it soft enough to remove? I don’t have any PLA solvents on hand.

Thanks for your help.

That sure looks like heat creep. Make sure the micro blower is working constantly and is pointed directly at the fins. Also keep an eye on your nozzle temps, a failed thermistor could cause nozzle overheating to a point it overwhelms the micro blower.

Put your finger on the heat sink while printing. It should be slightly warm, not too hot to touch.


Thank you. I got some of the filament out of the heat sink–hopefully enough–so I will try reinstalling the extruder head and check the fan’s consistency and the temperature of the heat sink. Will report back later!