Stubborn extruder clog
Hello! I've recently developed an issue on my MKS3+, not sure if this was the place or if hardware/software issues was the place but since it's my first post I figured here works.
I was in the middle of a print (prusament PLA, 0.3 mm layers) when the filament suddenly just stopped extruding. I tried unloading and the filament came out, but when I tried to load some new one it it would catch the gears but stop before anything came out of the nozzle.
I opened the side door and there's a really tiny nub of filament stuck just below the gears. I tried to push it out from the top both at normal and higher temperatures, (with motors and filament sensors turned off) but it wasn't moving. Then I tried to clean out the bottom of the extruder with a pin, but it barely went in a single mm before getting stuck, again both on normal and high temps.
I can't pull the filament out through the door with pliers, as it's too small to grab. Am I going to have to disassemble the entire extruder? Is there anything else I can try?
So you had some sort of clog which, when you unloaded the filament, pulled the tip and broke it off below the Bondtech gears.
Open the extruder. Careful prodding with a sewing needle should dislodge the nub if it is not connected to the body of the clog, If you can get it out heat the nozzle 10°C above the working temperature of the highest extrusion temperature of any filament you have used then take a length of PLA and manually push it down through the hotend until 20-30 cm have gone through finishing by pushing as fast as it will go then pulling the remains back out as fast as you can. The hotend should now be clear enough to use. If this doesn't work first time remove the nozzle and try again.
If the nub will not come out heat the nozzle and remove it, now push a stout needle or a length of 1mm wire up through the hotend - it may not go through but it should either lift enough filament to grip or at least to sever it - now clear with PLA as above - this procedure is quite likely to damage the PTFE lining tube so have a replacement ready.
And if none of this works then it's time for a replacement hotend.
Cheerio,