My AMS with the Slot 3 Problem

Bambu Lab AMS
1

Hej hej @ all. Beautiful greetings from snowy northern Sweden.
I’m usually a silent reader and, if problems arise, I try first and foremost to exclude myself as a person (operating error.) :slight_smile:
Just that first.
I have a P1S in combo with an AMS.
In my opinion (I still have a Viper, etc.), the P1s prints almost perfectly. The problem is this AMS… Completely in the special slot 3.
For example, he changes from slot 1 (2 or 4) to the 3rd without any problems.
BUT:
When he has to switch from slot 3 to another (no matter which slot) I always get the error message that he cannot retract the filament.
What I do then:
I remove the tube that goes into the top of the printer. then he can pull in the filament without any problems.

I have already printed out and installed a mod for the hub, changed the tube between the extruder and the first connection (i.e. the tube that goes outwards) and I have installed a swiveling arm that goes on the extruder.
Unfortunately the problem still remains.
Does ANYONE have an idea, no matter how crazy it may be? or had or has the same problem?
Thank you for your help :slight_smile: Kind regards, Chris
(I only print PETG and PLA at the moment)

2

Does the issue happen no matter what spool or brand of filament is in slot 3? Make sure the spool turns free and it not hung up on the sides or the guides, and the rollers are moving freely and are fully snapped into place.

Have you tried one of the many AMS feeder funnel buttons? Some use small pieces of ptfe tube as an entry point, other versions do not. There are a few different generations of AMS, so pick a model or two to try that seems like it will work with the type of push button your AMS has.

3

The AMS came with replacement tubes, replace it, make sure the new tubes face is parallel to the hubs teeth inside the base of the AMS, if its crooked when you check it to replace it straighten it and try it first do tests as you put it back together to make sure every step it can retract, unfortunately chasing ghosts in the machine is every hobbyist world

4

I had the same problem with slot 3 on a brand new P1S with AMS. Bambu Lab support helped helped to investigate and sent some spare parts.

I swapped first stage feeders, disabled and cleaned filament buffer and the problem almost disappeared. It now fails maybe in 3% of the attempts.