obewan

FYI I sliced your project file using cura 5.2.1 and it sliced perfectly, so it seems to be another problem with cura 5.3.*

please supply a project file, load the stl into cure and set it up to slice, then goto file/save as project and post the .3mf. The project file contains the stl and your printer settings.

I think it would be a lot easier to use the 'split' option in MS 3d builder (part of windows) then load the split stl's into cura.

You should do a G28 1st, then do G29 If you want a 3 x 3 grid try G29 P3

Can you share the STL pls

You can if you have mesh tools extension from the cura marketplace. Then you just r-click and split.

Not sure if this will help but i have printed sunlu pla+ at nozzle 225 and bed at 40 with no problems.

Could be you have coasting enabled . Also check retract extra prime setting.

It is because you have set a fixed infill line distance that overides the density setting. Click the f symbol on the left of the distance box to reset it.

can you supply the STL so we can have a look.

Try with union overlapping volumes unchecked

If you install 'mesh tools' from the cura market (top right in cura). You can then r-click the model and split into sepperate parts.

change the skirt minimum length setting

1/ click the 3 lines on righthand side of of profile and set 'all' 2/ scroll down the settings till you get to 'special modes' change surface mode to 'surface'

try selecting 'surface' in the surface mode section.

using cura 5.2.1 Setting number of walls=1 surface mode=normall slicing tolerance=middle This produces a spiralize gcode G1 X100.381 Y79.303 Z3.702 E120.44146 G1 X102.063 Y79.384 Z3.704 E120.49746 G1 X103.736 Y79.573 Z3.706 E120.55346 G1 X105.396 Y79.873 Z3.708 E120.60957 G1 X107.016 Y80.277 Z3.71 E120.6651

In special modes you have 'spiralize outer contour' ticked.

As a guess i would say the bottom of the model is not flat.

You need to increase the regular fan speed, otherwise it will stay at the minimum speed you have set at 15%. the print will start at the minimum value and ramp up to the regular speed at the set regular speed layer(which is layer 4) in your settings.

changing surface mode to surface gives a hollow model changing surface mode to 'both' gives a hollow model with infill below and above the windows.

can you post the stl

Another option if you dont mind glueing 2 halves together is to sink the model into the bed, upto the desired layer and reslice and print just the top part.

make sure the setting 'remove all holes' is not checked, in the mesh fixes section.

To me it looks like your model is sitting above the bed and so cura is generating a support under it. On the left side of cura there is a option to 'drop model to bed' , make sure that is selected.