I've made this shelf / rack that attaches to the underside of your table. You will need to print 2 left side pieces, 2 right side pieces and 2 cross section pieces for 1 shelf. The sides attaches with 4,0x30 mm screws. The shelf itself can be attached from the botton with m2 screws (Or just glue it in place). I've had great succes with the bambu 0.20 mm strength preset and i would guess that it can easily hold 10 kg.