Copperfill stuck in PTFE tube
Hello everyone.
I realise there are already a number of threads detailing problems with copperfill (or metallic PLA in general). While some have problems with print quality this has luckily been no issue for me.
I have however run into numerous clogs while printing a larger project. Clogged nozzles were remedied by using a larger diameter nozzle. For me, the main problem seems to be that after some time (usually around 2hrs) the filament gets stuck in the PTFE tube in a way that I cannot remove it, even after dismanteling the extruder and taking the tube out of the hotend.
I have amassed quite the collection...
One forum user suggested in an earlier thread that this might be due to heat creep in the extruder which apparently is exacerbated by the metal inside the filament. However after opening the enclosure to the chilly 10C in my garage this has not stopped the clogs from happening, or prolonged the time I am able to print before a clog occurs. In fact the last print did not get past printing the brim before the same problem occurred. For this reason I am sceptical if getting an extruder motor cooler is going to be much help.
Are there any other known causes for clogs of the above kind? Any help would be very much appreciated.
RE: Copperfill stuck in PTFE tube
I haven't used metallic filament so take what I say with a grain of salt.
You might want to consider a different PTFE tubing, I've used Capricorn tubing to replace some of my bowden tubes and hot end PTFE tubes in my printers. Capricorn tubing supposedly has higher temperature resistance, is more uniform in diameter over it's length and is more slippery than most PTFE tubing. I'm not sure if it'll solve this problem, but it's a fairly inexpensive thing to try.
Cheers
-Bob
Prusa I3 Mk2 kit upgraded to Mk2.5s, Ender3 with many mods, Prusa Mini kit with Bondtech heat break, Prusa I3 Mk3s+ kit
RE: Copperfill stuck in PTFE tube
I read this last night and went "Hmmm, strange".
Not being as tired tonight, it occurred to me that perhaps because of the thermal conductivity of the copper, heat is traveling up the filament and softening it in the region of the PTFE. It works fine while printing because is stretches enough to stay thin and feed. When you try to unload it, the reverse happens – the filament swells and there is too much friction to move it.
My thought is to pull the filament gently when unloading to keep it thin enough to move through the PTFE tube. If it has cooled down, preheat for perhaps 10-15 minutes before trying the unload it.
Jerry
RE: Copperfill stuck in PTFE tube
@Bob: Thanks for the tip with the tube material. Will definitely give this a try.
@Jerry: Unfortunately I am not even really getting to the unloading stage. The problem occurs while printing. If I finish the print before the clog happens unloading is not an issue.
Best
Henning
RE: Copperfill stuck in PTFE tube
Oh and ouch! Have you talked to the filament manufacture to see if they have any ideas?