Under mattress cup holder

thingiverse

I'm creating a custom cup holder for my 40oz water bottle that attaches to the side of my bed. It secures under the mattress to keep it firmly in place. Initially, I had issues with flexibility between the mattress and the ring holding the cup, but by placing it between my bed and nightstand, the problem is resolved. Although it's a bit too flexible, the water bottle can't tip over as it tries to lean out from under the bed. This setup works perfectly for me. I might not bother fixing the flexibility issue, but adding small ribs along the surface from the ring towards the mattress would likely stiffen it up significantly. My CR-10 MAX printer was used for this project, although I selected a similar option from the available choices since my model isn't listed.