Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
In Chapter 5 Step 30, I was able to insert the filament from the top and through the gears. However, the tip of the filament could only go as far as the top of the milky white colored funnel-shaped component. I cannot push the filament further in even with force. Even after I completed Step 32, I still cannot push it further down. Do I have to worry about this?
https://manual.prusa3d.com/Guide/5.+E-axis+assembly/1055?lang=en
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
Ummm. That white milky material is (I am guessing) the PTFE or Teflon tubing. And yes, the filament should easily slide down from the top of the extruder, past the filament sensor ball, Bondtech gear, into the PTFE, and a few cm farther to hit the nozzle.
If it is jamming at this point, you have a serious assembly problem.
Try this first: close the idler door and put a little bit of pressure on it and see if that helps to guide the filament into the PTFE. If that still isn't working, try bending a short length of filament so that you can try running it down from the gear into the PTFE directly. If you still can't get filament into the PTFE, somehow the PTFE is damaged and it will need to be replaced; which requires removing the hot end.
The best next step is to take a close up photo of the gear and PTFE and post it here so we can see what the problem looks like.
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
Thanks. Enclosed is a photo for your reference. I may be wrong but it seems that the filament and the PTFE seem to be not lining up on the same plane so when I inserted the filament, the tip touched the \/ shape-like opening part of the PTFE only. As one user mentioned, sliding the gears doesn't help because the issue is not due to misalignment along the x-axis but along the y-axis.
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
By y-axis, I mean in-out of the photo.
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
Just chatted with an agent. He suggested me to take out the PTFE to check the other end to see if there is anything stuck inside to prevent the filament from entering. However, this is not the issue here. It has nothing to do with the inside of the PTFE. The tip of the filament hits the \/-shape opening. It does not go to the center of the opening so it cannot get through. I asked for a replacement and he told me to finish the build first and preheat the machine to see if the filament goes in the PTFE tube. How does pre-heating solve my problem here?! I don't know if I am right or wrong. It seems to be related to mechanical misalignment.
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
It is a known fact the E-motor is displaced (by design, apparently) to one side, and filament path is not straight through the gears. There are user designed housings that move the motor into alignment. In most cases the alignment doesn't affect printing until you start printing Flex, and even then some people still have success. But is causes problems for some.
Have you tried trimming the filament tip at an angle rather than square? Or square rather than an angle?
The agent is probably hoping you will get to a point where you start printing and forget about the issue -- he's probably hoping the filament will load under power when you get to that point (heat has nothing to do with it). And in any case, he can't help since the parts you have is all Prusa has to offer.
All this aside, there are several threads on the issue: and a few have reamed the motor mounting holes to allow the motor to pivot and allow better alignment. Others immediately set about printing a new housing that is aligned properly. Do a search like this one ...
https://forum.prusa3d.com/forum/?wpfs=prusa+extruder+gear+alignment
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
ps: if your filament isn't perfectly straight, it can hang up as it moves down the extruder. I usually have to bend the filament to get any kinks out before loading - especially when loading from near empty spools.
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
Thanks. I did not trim the filament tip. (When I used the Stratasys uPrint SE, they recommended trimming at an angle. There was no such suggestion from MakerBot nor Tiertime.) So, it is better to do it for Prusa printers? I just inserted the filament from a new spool into PTFE during the installation-testing stage. I asked him to send me a replacement. He replied the following. We know that the problem is not filament not being able to go through the PTFE but not being able to enter the PTFE. I think another user also posted the same issue in the comment section.
| Sorry, a replacement for what? It's completely normal that the filament stops mid-way if the printer isn't preheated. |
| Complete your assembly, finish the built, preheat the nozzle, and you will be able to push it down further. |
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
It is a known fact the E-motor is displaced (by design, apparently) to one side, and filament path is not straight through the gears. There are user designed housings that move the motor into alignment. In most cases the alignment doesn't affect printing until you start printing Flex, and even then some people still have success. But is causes problems for some.
Have you tried trimming the filament tip at an angle rather than square? Or square rather than an angle?
The agent is probably hoping you will get to a point where you start printing and forget about the issue -- he's probably hoping the filament will load under power when you get to that point (heat has nothing to do with it). And in any case, he can't help since the parts you have is all Prusa has to offer.
All this aside, there are several threads on the issue: and a few have reamed the motor mounting holes to allow the motor to pivot and allow better alignment. Others immediately set about printing a new housing that is aligned properly. Do a search like this one ...
https://forum.prusa3d.com/forum/?wpfs=prusa+extruder+gear+alignment
Thanks. Based on long-term collective experience, what is the best course of actions at this stage of my building? I am in Chapter 8.
RE: Unable to insert the filament into the funnel-shapened component in Chapter 5 Step 30
Complete your build. The printer will most likely be functional albeit many of us do not agree with Prusa's alignment decision. If you trim your filament tips at 45 to 60 degrees, the Bondtech will drive the tip into the PTFE provided the idler door is closed and tensioned.
At this point, I would not print an alternative extruder. Get the stock printer up and running first.