Which is frustrating because we have to mostly take it apart to get all bits of plastic out. If we’re lucky it can be pulled upward. Any theories on why this happends? Printed fine for half a year until a few weeks ago and now every other print it stops feeding filament and we know… uhoh, it’s stuck again.
Temperature up or down, no difference. PLA only, different ones no change. Termistor is checked. Original settings nohelp. Tried tightening or loosening the screw.
The same happened to me, many times. I put it down to the PTFE barrel being tightened too much; the end of the barrel is tapered and so is the bottom of the hole drilled in the hot end, so if you overthighten the barrel, the end is forced down the taper and so becomes smaller, pinching the filament.
If there is a gap between the square face of the PTFE barrel and the hot end when the barrel is tight, this is a sign that this is the problem. Try trimming off the end of the PTFE barrel a small amount at a time until the gap is eliminated. The goal is to have the end of the barrel just touching the bottom of the hole, without any gap for the filament to be forced into.
With the barrel installed and the nozzle removed, you should be able to push a piece of filament through the assembly with very little friction.
Hope this helps, good luck!
Wally
After printing about 100, often two colour, prints I started having the same problem - particularly when changing colour. I also found that extrusion was becoming erratic - slubby and thin. Found that there was a blockage in the PTFE barrel. I cleared it with a drill with some improvement, but reckon there is still a coating of PLA at the bottom end. Looking to find a solvent to clean it properly. Methylene chloride would work - e.g. original Nitromors paint stripper. No longer available. Any ideas?
Soaked PTFE tube in B&Q brush restorer overnight - really clean - problem solved - for now anyway. Active ingredient 1.2.4 TriMethylBenzene in solvent naphtha (Probably white spirit)
