I'm having a lot of trouble with clogging now. The filament is clogging the PTFE tube above the hot end in conditions which have been working fine up until now. I have printed 1300 m of filament now. The tube is deformed and brown on one half, but I ran a 2mm drill through it and it works for a while. This time I flipped it around. Will it print like new again if I replace the tube completely? It's frustrating. Maybe I should make an all metal hot end.