I have almost completed a Mendel RepRap, but am still having some problems with the extruder. I am using the old Mendel extruder without gearing. I have followed the instructions pretty much exactly, but the plastic is not flowing through the nozzle nicely. It requires a lot of pressure to get it through. I have tried turning the heat up as well is moving the melt zone closer to the tip with no luck. I have taken the brass stud out of the heat barrier and done some testing with it separate and don't see any problems with backflow. Any suggestions...? https://reprap.org/forum/read.php?1,83501,83501#msg-83501 Sat, 13 Jun 2026 14:49:08 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,83501,83595#msg-83595 https://reprap.org/forum/read.php?1,83501,83595#msg-83595 -------------------------------------------------------
> How did you fix that? I might be experiencing the
> same problem wile printing larger objects. While
> printing the infill the extruder seems to jam in
> the PTFE barrier

I assume you are asking me brupje?

My thermal break was of the PTFE/PEEK variety. I purchased more PTFE and drilled out a hole to 3.1mm (same diameter as my barrel) and replaced the old PTFE containing the 3.5mm hole with the new section.]]> AgeingHippy General Fri, 13 May 2011 08:15:27 -0400 https://reprap.org/forum/read.php?1,83501,83589#msg-83589 https://reprap.org/forum/read.php?1,83501,83589#msg-83589 brnrd General Fri, 13 May 2011 05:13:17 -0400 https://reprap.org/forum/read.php?1,83501,83584#msg-83584 https://reprap.org/forum/read.php?1,83501,83584#msg-83584 brupje General Fri, 13 May 2011 04:19:18 -0400 https://reprap.org/forum/read.php?1,83501,83579#msg-83579 https://reprap.org/forum/read.php?1,83501,83579#msg-83579
One of the problems I had was that the inner diameter of my thermal break was bigger than the innerdiameter of my barrel. Under pressure, and given the plastic in the thermal break was softened slightly, it expanded to fill the space (3.5mm) and then jammed when expected to enter my barrel (3.1mm)]]> AgeingHippy General Fri, 13 May 2011 03:39:22 -0400 https://reprap.org/forum/read.php?1,83501,83509#msg-83509 https://reprap.org/forum/read.php?1,83501,83509#msg-83509 hydraraptor.blogspot.com]

You don't say which plastic, but if it is PLA then the top of the insulator can get too hot causing the PLA to go soft all the way up. Pull the plastic out while hot and see how far up it has deformed.]]> nophead General Thu, 12 May 2011 07:47:01 -0400 https://reprap.org/forum/read.php?1,83501,83501#msg-83501 https://reprap.org/forum/read.php?1,83501,83501#msg-83501
I have tried turning the heat up as well is moving the melt zone closer to the tip with no luck. I have taken the brass stud out of the heat barrier and done some testing with it separate and don't see any problems with backflow. Any suggestions...?]]> slouw General Thu, 12 May 2011 06:28:46 -0400