I designed this thing as a generative desing model, then I remodelled with hand.
The sizes are 120mm x 120mm, and I calculated for a 15kg weight with PLA.
This means if you print 2 pcs of them, then you can load them with up to 30 kg.
Print it with 100% infill!
I used 3M 2 sided glue (black one). It still holds my stuff in the bathroom before the window since 2 years (but only with 10kg).
No supports needed.
Shelf_support.stl | 3.2MB |