dsp

we had the same and I ended up reattaching the cables to the sensor which has solved it (our noise level was 1.6 to 1.8) Open the front of the head and check if the two cables are still firmly attached to the sensor, You can see this when just flipping down the front and see on the back side

The only filament backflow I had was due to the silicone cover that teared during the print. and we do a lot of dual prints. (about 70% of the time and the printer is used close to 24/7 for 4 years now)

for what I can see you have underextrusion raising the temperature usually helps i print my pla at 200°C and a print speed of 70% how fast is 100%? try fiddling with the settings but even with bad pla a better printing quality should be doable.

same here no more cover works fine having a 13day print destroyed because a cover was ripped was the limit.

Why not printing it top down? if i look at the print that would be more logical. But like GR5 states without the project file its hard to say why it turns out this way.

strange to me it really looks like a support issue, perhaps the bed adhesion failed on the print , but glad to read it's solved

no worries happens to all of us every once in a while, There are so many settings some get lost in the mass

When I read the explanation its normal to leave out tops when checked

AnaLara why do you have Spiralize outer Contour checked? If I uncheck it the top layer shows again

wait I was to fast now it still shows on 0.3mm layer height, I need to see what else changed during the change from normal to fine

I was able to replicate the issue in Cura 4.13 and if i change the from the normal ( 0.15mm layer) to fine 0.1mm Layer the top is starting to show. Try making you layer size smaller of make the top thicker.

@AnaLara: Can you post the model here so we can see what is going on?

how is the infill? or support if the part is hollow on the other side. It looks like there is not enough support below the top layer. can you post perhaps the model or UFP file?

Nee je geeft de oplossing zelf al compenseren in je model of je model draaien zodat het gat weer horizontaal is. het ergste is nog dat hoeveel je moet compenseren ook weer samenhangt met welk filament je print. De andere optie is na bewerken even met een ruimer door het gat of met een vijl.

Welcome Fred, I don't know the LAbist printer, So whats below is a guess... for as far as I can see the feeding system is with bowden tubes and a feeder that pushes the filament through the tubes just as the S5, I also read there is a broken filament sensor can you turn that off? The issue with TPU is that it is compressible like rubber so if the feeder retracts the filament. But in the head the filament moves less and later as the printer is thinking it should. this can trigger that sensor. But as stated before this is just a guess