Newbie and PLA woes...

Hello everyone! New to the forums here (and printing for that matter), though I’ve had my TAZ 5 for about a month now. I’ve been lurking through quite a few posts and I find people with similar issues that I’ve been experiencing but I still have questions. Especially since I’ve run into a huge problem!

I started out with a roll of the Lulzbot natural ABS and nearly finished it so I decided to switch to the Lulzbot grey PLA to see how that behaved. It took some work to get the ABS to clear out of the nozzle and change to the grey but I got there and everything worked great. I printed the test file with the Venus de Milo and finished that in 3 hours just fine. I decided to start a large print, printing at 200 with the bed at 85. Only an hour in, the nozzle stopped extruding and what was still coming out was stringy. Reading the forum I found the “heat creep” issue and figured this is probably the culprit. I stopped the print and attempted to take out the filament to clear it like I’ve done before with the ABS, which was super easy. The filament broke off just above the hobbed bolt and will neither extrude or reverse. The filament is also chewed up and will not pull out with pliers, nor could it be pushed through with the sharp metal punch that came in the tool kit. I tried heating the head to 230 and it is still stuck. I’ve also read that acetone makes more of a mess of PLA than helps. How on earth do you clear a clogged head of PLA? I figured taking it apart and scraping it out is an option but is there an easier way?

Sorry for the long winded post, just trying to be as descriptive as possible. Thanks for listening!

So you’ve tried heating up the PLA, unlatching the idler and pulling out the filament… Grabbing the filament after the hobbed bolt?

If filament has melted or swelled in the heat break or lower end of the hotend, then it may require some drastic measures. Disassembling the extruder, heating up the hotend, removing the nozzle and pushing the PLA filament out. (with ABS). Removing the nozzle will allow the filament to be pushed out without the constraint of the tiny opening. Using ABS (at PLA temps) should keep the filament from melting and allowing it to “push” the PLA through the heat block… To get the filament thrpugh the heartbreak, you may need to disconnect the little blower to induce heat creep…

I would contact Lulzbot support for suggestions before trying the above…