MK3S Upgrade & Clogged Hotend
Has anyone had problems with repeated hotend clogs after installing the MK3S upgrade kit? My MK3 was working fine on before installing the kit. After the MK3A upgrade, any extended print inevitably results in a clogged hot end. It clogs between the PFTE tube and nozzle.
RE: MK3S Upgrade & Clogged Hotend
Hi Winston, Yea I had similar issues when I updated my build from the MK3. The new PTFE tubes that Prusa is sending out has a smaller diameter compared to the one that came with my kit. the internal diameter of the new PTFE tubes were between 1.78 and 1.81. Compared to the previous PTFE tube I had which was 1.85 to 1.88. While that may not sound like much over time during a print (Especially PLA) the PLA will change in diameter slightly due to heat and compression. This causes the PLA filament to get larger and increases friction in the tube which causes a snowball affect.
I sent an email to Prusa support and they provided a new PTFE tube however, its still quite smaller than the original one I had.
The way I resolved this issue is by reusing the PTFE tube that came with my original kit and cutting it slightly shorter since the MK3S upgrade has a shorter PTFE. Since I've done this the issue has not occurred after multiple prints. This yields me to conclude that the new PTFE tubes are causing this issue.
RE: MK3S Upgrade & Clogged Hotend
@patrick-m51
That’s interesting. I replaced the PTFE tube several times with the MKS3 version of the tube but it still clogged continually. I just replaced the entire E3D hot end assembly with a new one from prusa and have had no problems after several prints.