Is this heat creep? (TAZ 5)

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Star Hen
Posts: 5
Joined: Wed May 04, 2016 4:50 pm

Is this heat creep? (TAZ 5)

Post by Star Hen » Sat Jun 24, 2017 8:56 pm

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. :? 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: http://i.imgur.com/rYP803a.jpg 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 :(), 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: http://i.imgur.com/I2YDDxu.jpg 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): http://i.imgur.com/t6bHI3U.jpg. 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.

gghouck
Posts: 197
Joined: Fri Oct 03, 2014 11:35 pm
Location: Seward, Alaska

Re: Is this heat creep? (TAZ 5)

Post by gghouck » Sun Jun 25, 2017 11:57 am

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.

FCLOWELL
Posts: 43
Joined: Mon Feb 08, 2016 11:34 am

Re: Is this heat creep? (TAZ 5)

Post by FCLOWELL » Sun Jun 25, 2017 8:09 pm

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

Pete

Star Hen
Posts: 5
Joined: Wed May 04, 2016 4:50 pm

Re: Is this heat creep? (TAZ 5)

Post by Star Hen » Mon Jun 26, 2017 3:30 pm

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!

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