From what I have read, the most common failure mode is the extruder jamming or the tip coming loose. Less often the X and/or Y axes loose lock. What other problems are people having that us newcomers should watch for, and designers should be thinking about fixing. In particular, how important is the glass nozzle in reducing extruder jamming, tip popping out, coming loose, or getting off center? Is this a common problem, or not worth changing out a working extruder for? Mike https://reprap.org/forum/read.php?1,56135,56135#msg-56135 Tue, 16 Jun 2026 08:24:49 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,56135,56432#msg-56432 https://reprap.org/forum/read.php?1,56135,56432#msg-56432
A glass nozzle will reduce my failure rate if the friction in the small hole is less than the stainless steel nozzle I have now.

I have also been observing a strange issue. If I don't shut down my heater right away when the extruder jams, then the next time I run it, it will be more likely to jam again. It took me quite a while to recognize the pattern because I can restart the extruder (with a little push at first) and it runs, but only jams again after 1 or 2 hours of operation. It will continue to be unreliable until I back-out the PLA and clean the barrel. I know someone else with an extruder that is very similar to mine and he describes similar behavior.

My working theory is that the PLA that is in contact with the heated nozzle for a long period of time changes in some way that makes a residue that adhere strongly to the nozzle. Since it also sticks well to PLA, this means it greatly increases the friction in the nozzle. When I clean the nozzle, I have to run the temperature up and back out the filament. During this time, the residue will be heated and exposed to air, which causes it to burn up and go away or turn into something that isn't as much of a problem. A glass nozzle could help in two ways. First, I could observe the residue forming, breaking down and then being cleared away. Second, it is another material and maybe the residue doesn't adhere to it as well.]]> mccoyn General Mon, 23 Aug 2010 15:28:05 -0400 https://reprap.org/forum/read.php?1,56135,56310#msg-56310 https://reprap.org/forum/read.php?1,56135,56310#msg-56310
Mike]]> rocket_scientist General Sun, 22 Aug 2010 19:43:37 -0400 https://reprap.org/forum/read.php?1,56135,56290#msg-56290 https://reprap.org/forum/read.php?1,56135,56290#msg-56290 nophead General Sun, 22 Aug 2010 15:23:17 -0400 https://reprap.org/forum/read.php?1,56135,56279#msg-56279 https://reprap.org/forum/read.php?1,56135,56279#msg-56279 spacexula General Sun, 22 Aug 2010 14:28:29 -0400 https://reprap.org/forum/read.php?1,56135,56277#msg-56277 https://reprap.org/forum/read.php?1,56135,56277#msg-56277 what size nozzle opening would you like? I think I can get some down to 0.2mm that will not jam, possibly smaller.


Mike]]> rocket_scientist General Sun, 22 Aug 2010 13:28:20 -0400 https://reprap.org/forum/read.php?1,56135,56206#msg-56206 https://reprap.org/forum/read.php?1,56135,56206#msg-56206
I can run reliably without the extruder jamming, but I'd like to be able to run faster or with a smaller nozzle. Whenever I try to push my machine in one of these ways the extruder jams.]]> mccoyn General Sat, 21 Aug 2010 15:56:00 -0400 https://reprap.org/forum/read.php?1,56135,56135#msg-56135 https://reprap.org/forum/read.php?1,56135,56135#msg-56135
Mike]]> rocket_scientist General Fri, 20 Aug 2010 20:26:45 -0400