Filament stuck above heatsink stopping filament from being loaded
I finished assembly of my Prusa mk3s a few days ago and had great initial results, but suddenly when changing the filament to a new spool I guess some broke off and got stuck. I have tried heating the nozzle, using more filament to push it through, trying to chip it away with a drill bit (not actually drilling just chipping at it), and I can't think of what else to do. I am using PLA from matterhackers. Thanks for any help.
RE: Filament stuck above heatsink stopping filament from being loaded
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Raise Z to max.
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Open the extruder housing door.
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Inspect the top of the white PTFE tube below the gear. If you can see the top of the snapped filament, use tweezers to pull it out.
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Set nozzle temp to 285C.
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Use a 6in/15cm 1.5mm rod (e.g. brass available from hobby stores) or a small hex wrench to poke down from the top, past the open Bondtech gear and into the PTFE tube. With any luck, you'll be able to push the stuck bit down into the hotend where it'll melt and be extracted, or at least far enough you can feed filament down after it. Brace the extruder with your free hand to avoid twisting, and don't press too hard.
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You can also try removing the nozzle and poking from above or below.
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If you encounter an obstruction that won't ease out, try holding the rod with pliers and pushing from below. The rod will heat up and hopefully melt whatever's blocking the path, poking up and out of the PTFE tube to where you can grab it.
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: Filament stuck above heatsink stopping filament from being loaded
Hi bobstro, thanks for replying. I tried this with a brass rod today and when that didn't work I also removed the nozzle and yet there still seems to be a blockage somewhere that is stopping filament form loading. If you have any more ideas I would greatly appreciate the help. Thanks!
RE: Filament stuck above heatsink stopping filament from being loaded
[...] I tried this with a brass rod today and when that didn't work I also removed the nozzle and yet there still seems to be a blockage somewhere that is stopping filament form loading. If you have any more ideas I would greatly appreciate the help. Thanks!
If you've removed the nozzle, try heating the nozzle temp up to 285C and using pliers to hold the rod and insert it from below until you encounter the obstruction. Brace the extruder to avoid twisting, and apply gentle upwards pressure. With any luck, the rod will heat up and soften whatever's blocking the path and push it up or break it up.
and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: If you've removed the nozzle, try heating the nozzle temp up to 285C and using pliers to hold the rod and insert it from below until you encounter the obstruction. Brace the extruder to avoid twisting, and apply gentle upwards pressure. With any...
I just tried this and the blockage does not even budge. I have it on 285 degrees and am pushing from the bottom. I cannot feel any movement of the blockage but the rod goes up the extruder hole around an inch or so before encountering the blockage. I have tried pushing from different angles and stuff. Thanks for the help and anything else you can think of will be greatly appreciated.