Blocked filament

I have a problem that the filament gets blocked in the PTFE tube in the isolator guide.
I have cleared the tube from filament but when I restart a new print process the filament gets blocked after a short period of printing.
What is the solution to this problem?

[quote=“pannekoek”]I have a problem that the filament gets blocked in the PTFE tube in the isolator guide.
I have cleared the tube from filament but when I restart a new print process the filament gets blocked after a short period of printing.
What is the solution to this problem?[/quote]

What retraction length did you set?

Ichbinsnur has a very good point.
I set mine to 5mm I have also set the Extruder temp to 195C
You may also want to check the thermistor for proper installation.

I have the standard Vertex values 5 mm retraction and 210 C.
Are these values not the best?

I think the retract is normally set for 9mm.

You may have to experiment.

It could be the same problem I had, probably not, but easy to check.

The last 5-7mm of the PTFE tube, that’s facing the extruder head, had somehow got a thicker inside diameter, resulting in that the filement could not be fully retracted OR moved down into the extruder head during print.
(I do have a hard time writing this in English, but I do have a image here):

The solution for me was to make a new inner tube. After that, my prints started to go well again.
It was a pain in the a** to replace the inner tube, but with some patience I finally made it.

elHatchling is right. The PTFE tube has to have the exact length as specified in the manual (23mm) and that’s also why the isolator tube has to be cooled.

Just to clarify. My original tube was (around) 23.10 mm then I assembled the printer the first time.
The left part of the filament in the picture is 1.75mm, and the right part is > 1.75 mm (I measuerd it, but can’t remember the exact diameter right now).

The PTFE tube has (I don’t know why) got wider in the end facing the printer head.
Maybe it’s not as temperature tolerant as it should be…

Thank you for sharing. I will work with it!

Glad to help out.
Please report your findings here, maybe it can help someone else.

I have been to my supplier and there to filament was unblocked.
But after some hours of printing the problems was back.
I have now dismounted the extruder and removes the tube. But this do not look as bad as yours.
I have made a picture but I do not know how to include this in the post.
I wil inform later when the printer is back into operation.

Use a photo upload service like tinypic.
After the upload you need to copy the link with the [IMG] tags and paste it here.

Cheers,
Dylan

[quote=“pannekoek”]I have been to my supplier and there to filament was unblocked.
But after some hours of printing the problems was back.
I have now dismounted the extruder and removes the tube. But this do not look as bad as yours.
I have made a picture but I do not know how to include this in the post.
I wil inform later when the printer is back into operation.[/quote]

Hi, my tube looked that way AFTER I tried to remove it (it’s probalbly rust from the smallest tool I had avaliable to try to rip the tube out.)

The question is if your inner diameter has expanded beyond 1.75mm?
It sounds exactly like the problem I had, could print for 30mins or so and then it blocked again.
The blockage was beqause the filament could not push down into the extruder.