This is my modular loader bucket design made for 3D printing.
This is printed with stock Creality Ender 3 V2 - a printer with one extruder/hot end, so the design takes into account the overhang of first layers over the supports and thus:
Print profiles for Cura 4.9 are included in the zip file - download the zip file instead of STL's separately as it has folders organising things. There are explanation screenshots from Cura showing the valid orientation of each element which is important for the surface quality and orientation.
YOU MUST ORIENT CURVED PANELS PROPERLY - there are tolerance gaps made in order for it to be modular and fit with sides properly in each direction. This means when you take a look at the Technic pin sockets in curved panels, you'll see that on the bottom of the hole there will be only 4 layers while on top of the hole there will be 6 layers. That is because first two layers will overhang filling the gap between the interface and bridge layer which is 2 layers thick - with 1 layer thick gap detaching the supports gets really hard.
Most of the parts should be printed with PLA while the sides are supposed to be printed with PETG as it's the easiest element to print with PETG and it doesn't have actual axle sockets for connection with bottom piece, but it relies on some flexibility of the material holding the axles.
You need 20x black 2L Lego Technic pins and 2x black 6L Lego Technic axles. Additional long axle is required for disassembly.
If you want to perfectly fill the gaps between curved panels, I'd probably try using some matte black nail lacquer or base colour lacquer fix for cars and put it gently with a toothpick on the edges.