Extruder PTFE connector - check yours

I’ve been experiencing some issues where it was very hard to get the filament out of the extruder, like something was binding. Also the filament detection sensor started acting up and kept detecting filament even when nothing was in there. Sometimes when running filament through it, I had hard time getting it to feed - it was suddenly more fussy about the angle I inserted the filament at.
I did the usual - blowing it out with air without much disassembly and it fixed itself for a week.
Yesterday I had a clog, and while dismantling it, tiny filament “guides” fell out of the extruder. It was formerly on the inside of the PTFE connector on top of the extruder and they were just ripped out and all over the place. I think this was the cause of my problems and thankfully it didn’t get deeper inside and didn’t destroy anything.
I’ve removed the filament detection part and got the PTFE connector out, it is simple to replace.

The purpose of this post is

  1. if you are having problems, check your to see if your guide have disintegrated. In my case it was almost certainly caused by abrasive filaments and clearing clogs by cold pulls through the extruder

  2. anybody know what the replacement part is? I can’t find a “header” like this


Ya those ptfe connector must be Bambu only I have never seen that type also.

I don’t know if you can get something like this to work by removing the internal parts and repairing the Bambu connector internals or by 3D printing an adapter.

Small PTFE Connector

Or maybe lock your ptfe tube into one of the Bambu ptfe guides for now until you get a part.

Thanks for the link. I’ll try and see if it fits.

The connector still works, it just has that broken “guide”. In fact, that metal part can be removed from it and could be replaced, but I think finding that one would be even more tricky :slight_smile:
It is a bit chewed up, I think it’s the most consumable part of the extruder by the looks of it. Maybe I’ll try BL techsupport to see if they want to provide it as a spare part.

I had a spare (used/unclogged) extruder and ordered a new one, but changing the whole extruder is not the right fix there :smiley:

P.S. Created a ticked with support and will come back with the result…

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I don’t know if they are the same but I just noticed the tube coupler fitting on the back looks close.


Got reply from BL support:

At this moment we don’t have this part as a separate spare part but it will be added to the webshop very soon.
This will be as a part of the “filament sensor”.

Sounds acceptable to me, should be pretty cheap.

@3DTech I was thinking the same thing and I actually just got a spare one. I wonder how many people have this part broken without them knowing - the ugly thing about that is, that it might go unnoticed for a while, just getting weird AMS/feeding problems or possibly extruder chewing the small metal bits up

Seems BL still hasn’t added the filament sensor as a separate spare part. The pneumatic fitting on my sensor died sometime last night (woke up to a chamber full of filament). I’ve also searched for a fitting like the one they use, but no luck. Have you found a suitable replacement fitting? I also don’t want to buy a new extruder unit, just for the fitting. Buying the sensor is a bit better, but, I’d still rather just have a box of those fittings!

So yours failed catastrophicaly and the bowden came loose? That didn’t happen on mine, it just impeded filament movement somewhat and the “fins” found their way into extruder (where they thankfully did no damage but could have).
I have 2 spare extruders and I am waiting for that spare part to be available, maybe try messaging BL again and ask about it’s availability?

FYI, the dual PTFE connector on the back on the printer can be split open and the connector can be easily swapped in the filament sensor. I have three extruders where this sensor failed.
Also, when this part fails, the metal parts from the inside of the connector get stuck in the filament sensor because it’s magnetic, so check yours if you have any weird feeding errors.

So you mean the PTFE tube connector,
not the PTFE coupler P1 Series

Do I get this correct?
As my sensor also just got broken and I found small little metal parts in the extruder (after the print stopped all of a sudden) and located the PTFE coupler as the root cause.
I cleaned the coupler from the rest of the small metal parts and now the printer is working again, but without any AMS functionality. As the PTFE tube is not fixed any more…

Just as a small side node: it is the PTFE tube connector.
In the extruder you can simply slide it out to the side.
And then use the black labelled connector from the back. Useful when you plan to install a Y splitter in any case.