Help with AMS settings

Is there a good tutorial somewhere on what settings to use with an AMS? I have a P1S and it works great, but the AMS is iffy at best. The actual device works just fine, but there are issues when using it. I don’t know if I am just expecting too much from what an AMS can do, if my settings need adjusting, or what. Everything is pretty much still stock settings and whenever I download a 3MF File from the Bambu Lab’s Studio, I make no setting changes other than to adjust the filament brand, or printer type. I have started adding rafts to models to ensure better print adhesion, but that is it.

First issue I have: The machine purges (what I feel) a lot of filament between changes. Sometimes it feels like I am using as much filament from changes as I am on the model. This is also causing an issue where the ‘poop chute’ is getting clogged near the top, even though there is nothing stopping the extruded filament from falling down the chute and out the back. This often causes the cover on the hot end to get knocked off, which halts the print, and in some cases has knocked over the print as well, causing a print fail.

The Second issue I have is with prints failing because of filament changes. For example, the most recent model I tried to print was a 3" tall snowman. 3 Colors (red, black, and white), it is a cute but simple design and only used here as an example. However there are often issues with supports failing and loose strands of filament getting everywhere.

The AMS works like a charm on short items that do not require a lot of changes per level, for example, a multi colored sign. I did a thin (maybe a few MM thick) Grinch that hangs off a shelf. Had 4 colors, printed great. But if I print something over an inch or two in height, there will be some sort of failure.

In the case of my most recent print, it was 3" tall, would take 26 hours to print at the settings provided, had 3 colors, and failed at 44% due to a number of areas not printing properly.

Sounds like you have having adhesion issues, not AMS issues.

Keeping the bed clean and free of contaminants such as fingerprints is key.

No, it’s not bed adhesion, I did have that issue, but it was mostly eliminated by adding a brim. The Models stick to the plate, but at some point, midway up, things go wonky. supports start to fail, or the chute get’s clogged and the cover comes off, which, if a support has minimal infill (as the usually do) it could break. I have also noticed times where a large mass of poop is laying on the build plate. My guess is that the mass did not go down the chute like it should (chute is not clogged, just stuff staying at the top) and when the nozzle moves away from the chute, it drags the large mass out, which could also be causing some stability issues.

Can you share a Timelapse video and photos of the failures?

You can solve some of the stuck poop problem with a touch of silicone or dry lube spray. Move the head forward and remove the print plate before spraying and don’t overdo it.
Spray from the back. Might be better to spray a paper towel and wipe the shoot.