Print head leaves filament residue that causes print failures

[Flesch]

Hello 3D printing friends,

for a few days now, when the print starts, the print head creates a blob or drags some filament behind it. This ends up being in the way of the second layer, and in most cases, the print head just completely tears the printed piece off the bed. So far 75 % of my prints are faulty.
I’m not sure if this is connected to the last firmware update, but I didn’t have these kind of issues before.

I’m currently using a 0.6 mm hardened nozzle with the standard textured PEI plate.

I tried to adjust the initial layer settings, e.g. flow rate and speed, up and down, but that didn’t change much. Since I didn’t have this problem before, I don’t even know where to look for.

Any suggestions?

[JonRaymond]

Welcome to the forum.

How are you cleaning your plate? Looks like adhesion problems to me.

[Flesch]

I usually use a microfiber cloth with 70% IPA. Today, I also washed the plate with dishwasher detergent, as recommended by Bambu Lab.
You can see that the print head is dragging filament strings behind it. I don’t know if it’s because it doesn’t stick to the plate or because it keeps flowing out of the nozzle.

This happened 2 min ago (I hit stop when I saw the mess of filament on the print bed):

[Flesch]

Now that you mention it — the end of the test line gets thinner. Is that the material that ends up in the middle of the print later?