I’m running into a recurring issue when printing dual filament models on a full plate. Due to longer layer times, the idle nozzle tends to accumulate material. When it becomes active again, it drops a glob onto the prime tower.
Eventually, these globs build up enough to interfere with the nozzle during priming, knocking over the tower and causing a layer shift. The taller the print, the more likely this happens.
This just happened again—with 3 hours left on a 2.5-day print—so I’m looking for a more reliable solution. Photo of the failed prime tower is attached.
Ideally, I want the prime tower to go back to being just a prime tower—not acting as a nozzle cleaner too. Would re-running flow rate calibrations help?
Also, is anyone aware of:
A setting that forces a nozzle wipe or clean at the end of each layer?
A way to insert custom G-code to do this?
Or any other method to reduce buildup during long idle periods?
I’m not concerned about adding print time—just looking for reliability.
I don’t have an issue with the existence of the prime tower. It’s purpose is to assist in priming the nozzle, which is what I would like to get it back to doing. Rather than priming and cleaning the nozzle in this situation.
You may want to revert to the regular prime tower and adjust the width to make it very wide. That way it should have good bed adhesion for forces in the X direction when the blob hits your tower. I have the same blobs on mine but it has not caused a failed prime tower. What material are you printing with? You could try playing with the Retraction length to see if you can reduce the blobs.
@Pnw there’s a bug about prime tower with the Bambu Studio 2.1, which is solved in 2.2 Beta. Basically for 2.1 the tower is doomed to fail once it had enough filament changes.
You can download the new beta from Github.
Also, you should use the new style of prime tower, which is designed specifically to absorb that blob.
Ah, I didn’t realize the new tower helped with the blobs. I’ve only been using it when running alot of supports with interface material. I’ll test the new tower on the next version, and possibly pull in the beta slicer.
I’ve been having the Prime Tower issue again since the last Studio update. Whether I’m using the new or the old one doesn’t matter. I could see how the nozzle stuck to the tower more and more tightly the higher it got, until it finally toppled over.
In the video in the link, I tried to save the print by propping up the primtower with magnets, but it kept getting knocked over. Even when holding it, you could feel how tightly the nozzle was stuck to the ohm cert.
in general for dual color the nozzle shouldn’t have that much of oozing, unless your filament is wet. also check if your nozzle blocker is working properly
I dried the PLA for 10 hours today at 50 degrees Celsius and will now try printing again. I can report back tomorrow morning whether it was due to the humidity.
I was only able to complete the print today because I put magnets on the primer tower right at the beginning. It was wobbling a lot and had already come loose on one side. So it’s not a drying issue. It must be Bambu and the studio.
The right tower is the undried filament, the left is the dried PLA. It was 50 degrees Celsius for 10 hours. The humidity in the AMS was 17% and 13%.
I’m having the same issue, possibly related to the latest Studio update. Same dried filament is now suddenly oozing and creating spaghetti on the prime tower.
