This is a simple shelf insert I designed for my kitchen cabinet.

The original model is 246mm wide (feet spacing + foot width + margin) by 280mm deep and the shelf is 6mm thick, and the top of it sits at 134mm.

You can adjust the design directly into MakerWorld's customizing tool.

Once you've modified the design to your likings :

1. Donwloaded the 3mf file
2. Open it in Bambu Studio
3. Split it to objects (right click > Split > To objects)
   
4. Re-arrange the parts for printing 
   1. Use the Auto-orient to lay the feet on their side
   2. Use the Arrange all objects tool so the parts are properly distributed on as many printing plates as needed.
      Make sure to not leave the Spacing at 0.
      
5. Print & enjoy!