Consistent Jams with PLA on Taz6 Heat Creep Issues

Hey guys, new owner to the lulzbot line of printers though I’ve used them before. I have a taz6 and after about 20 hours of successful prints, I’ve been having consistent issues with continuing prints. For the first 2-3 hours, the printer works just fine but anything longer than that, jams seem to occur where the filament gets melted and jammed up on the grub screw in the extruder. Forcing it down doesn’t work as its firmly implanted into the grub screw area and sides so the only option is to disassemble and unscrew the grub screw from the hotend and remove the filament from it. All fans are functional, I don’t have any other material to test with but the test filament worked just fine (though shorter print times) and now with my PLA, its been nothing but issues after a few hours. I’ve read heat creep being an issue on the 5 and people fixing it with 40mm fans but not much on the Taz6. I’m using Simplify3d on default settings for the Taz6, print between 60-80mm/s, 60,70, and 80 all failing due to the same issue, temps set to the manufacturers suggested temps.

The Taz 6 has a larger fan on the barrel, so it generally isn’t subject to the same fan issue the Taz 5 had with the partially failing squirrel cage fans. You do want to verify that the middle fan is operational and running constantly. It is possible to overcool your nozzle block and cause jamming. Overextrusion can also cause jamming by making the part surface too close to the nozzle. crappy filament can also cause similar effects.

If it seems to be a hardware issue though, you should definitely call support since you are under warranty.

Thanks for the response, I had been searching on the issue and saw it was more of a 5 issue indeed. Though I’ve tested it with 6 different brand of filaments and still seems to occur. Already have some replacement fans packed away so I’ll swap it out to see if that helps.

You use the term “grub screw” and to me that means set screw (small threaded section of rod, with a hex shaped hole on one end). Are you referring to the hobbed bolt that feeds the material into the hot-end?


I am noticing what I think is heat-creep issues to. printing T-glase on high-strength and a part with lots of retracts…prints for a while, then strips the material.

Not sure if the basic fan it came with is doing it, it seemed very weak when I pulled it off to feel the flow. I will put a temp probe at the top of the hot end (just above the fan shroud). What is the max temp it should read? Nozzle is it 245.

Well my T-glase issue was not heat creep. turns out T-glase does not like an enclosed chamber. After leaving the front door on my chamber open, T-glase has no problems.

But I did end up ordering some higher flow 5V fans, and may still put one on.

If anyone is interested in upgrading the hot end fan I suggest looking at:
SanAce40 109P0405H601 (almost double stock flow rate)
SanAce40 109P0405H3013 (almost triple stock flow rate)
Got them on amazon.