Simple Secret Box II: Coin Bank.

cults3d

https://www.youtube.com/watch?v=PLkKVC_n0Go "Simple Secret Box II: Coin Bank" is a coin bank designed with a secret locking mechanism that teaches kids to save money by hiding the opening method from them. This design was inspired by my Apple Coin Bank model, but adds an extra feature - if the kids want to make an early savings withdrawal, they'll have to figure out how to open it first. The box features dovetail fixed joinery and a sliding dovetail top, making it a challenging puzzle for kids to solve. The locking mechanism is based on the German-designed "Radbox," which uses two mirror-image slotted wheels to keep the box closed. My design takes a different approach, using cam-shaped slots instead of wheels, but the principle remains the same. The locking mechanism is cleverly hidden from view even when the box is opened, adding an extra layer of fun and challenge for kids. I couldn't find the original designer's name, so if anyone knows it, please let me know so I can give them proper credit. Building this model requires no complicated hardware - just 3D printed parts. This simplicity was one of the reasons I enjoyed designing, printing, assembling, and testing Simple Secret Box II: Coin Bank. If you have any questions or notice any mistakes (I'm prone to forgetting files!), please don't hesitate to ask. I designed this model using Autodesk Fusion 360, sliced it with Cura 3.4.1, and printed it in PLA on both an Ultimaker 2+ Extended and an Ultimaker 3 Extended.