Using Limonene to unplug hot end

Hi all,

I was wonder if I could use limonene to dissolve a HIPS blockage I have (I would disassemble the toolhead - so none would touch the ABS).

It’s in the upper end of the hotend (the header block is empty of plastic. I can’t seem to get it hot enough to melt it out (cranked it up to 290º and tried to push it through with some filament as per the instructions, didn’t seem to do anything).

I can’t pull it out, as it’s flush with the plate (snapped during to an attempt at pulling it out).



I spoke to LULZBOT tech support about this exact same topic of high heating the hot end and they strictly advised not to do it. They said the filament could crystallize inside the hot end. The best bet is to use nylon and do the cold pull method to remove a blockage or partial blockage. I had an issue with the MOARSTRUDER bubbling and popping and initially I thought it was the filament but it was a partial blockage. I tried clearing it with PLA but it didn’t work. I tried a higher temperature on the hot end and extruding filament and it didn’t work.
What did work was using the nylon at the rated temperature and doing a cold pull 5 times to completely clean the extruder.

If you are not familiar with a cold pull here is the process:

I hope this helps!


Hi Svanwhy,

Thanks for the reply.

Based on the link you sent me - if there is no flow - for filaments other than PLA, the recommended procedure is to try to clear it by putting the temp up to 290º (first step in the first section).