I was tighting up my bulldog XL because it would advance the filament then stop then advance it again. I finally got it to stop but it pushed the copper part of a J-head out of the PTFE. took it apart to find the bottom half with a bunch of plastic. Not sure how to get it out. The red thing behind it is the PTFE tube and it looks like it has melted a little from the pressure and heat.
I have been right at the top then at 245C. Ive printed at this temp for a long time now and never had a problem. Today I switched out to my bulldog XL extruder and to some black filament
Overnight acetone is a good loosener of filament-cement from clogged heads. You’ll still need to extract the softened filament but it’ll be much easier.
If parts are still stuck after an acetone-overnight, a little heat from a torch onto metal will loosen the rest. Just don’t burn yourself (like I did, minor irritant) and pay attention not to damage/melt plastic pieces.
Yah at 245C the PEEK will soften but if there’s no flow/block issue it’ll print fine.
Fire or Acetone will work. Though in most cases once the PEEK part has been damaged (in this case by the nozzle being forced out) the J-Head is not usually recoverable.
Check the thread in the PEEK section is still fully intact for you to screw the hotend back in.
A butane torch worked well for me. You can use just about anything that makes a clean flame. Just be sure not to over heat it (bright glowing), and let it cool slowly.