Everyone should have a lucky marble! It's powers can not be quantified, but whatever your goals are, the lucky marble will serve as a beacon of positive energy... or maybe it's just a fun fidget keychain :P

While everyone must discover their own lucky marble, I can provide you with this holder. The strong press-fit shell ensures you won't lose your precious amulet while letting the ball smoothly roll around within for a very satisfying sensory experience.

Use a heavy metal ball for an excellent sensory grounding device. Such tools are often used to treat anxiety. The repetitive motion of rolling a ball can activate the parasympathetic nervous system—your body’s "calm down" mode. I find the 20mm version with a steel bearing ball is an excellent size and weight to add to your keychain.

Printing Guidelines

Print solid at 0.16mm layer height. The download includes several sizes, labeled by the size of the ball. The tolerances are very tight, so it is best to measure your balls diameter with a digital caliper. If you need a size not included, leave a comment and I will do my best to add it to the collection. You can also slightly scale up the models if the fit is too tight (rolling action will also get smoother with some use). Some glass marbles are not round enough to roll smoothly.

Some force is required to snap in and remove the ball (for it's own protection!). For assembly, you may want to place the print on a hard flat surface with the larger opening facing up. Place the ball on top and then push down on it with your palm or another firm surface.