Small Airless Ball

This is a 3D printed ball. Please use it at the size it is set to. I believe the wall thickness to lattice sizing is critical to maintain, and that this will become distorted when scaled causing the part to fail. 

I recommend printing in PLA+. I don't have the capability to use nylon-reinforced PLA or carbon-fiber PLA, but I have a hunch that those filaments will be superior to the one I used.

It is critical to use aligned seams. I printed at 0.3mm layers at 100% infill. I used organic supports using smart fill in prusaslicer to only adhere supports to the outside of the model with a 0.3mm spacing between support and model. 

Please note: This is plastic. If you hit a sharp object like a rock, or throw it too hard it will break. It can withstand low-moderate forces like bouncing from waist height. From my tests, it retains a 60-80% bounce depending on the surface. 60% on indoor floors, 80% on concrete/harder surfaces. It can bounce like a basketball, but if you put some force into the throw or throw it up very high, it will break. This is due to limitations of the material selection. Again, it is plastic, so respect its limitations.