Modular Storage Rack

Dr Alexander Paul Cave

Project Description

I recently completed my first industrial design project: a modular, expandable racking system designed for a popular IKEA storage box. This project was designed using Autodesk Inventor and fabricated with a Creality K1 3D printer.

The concept was to create a storage system similar to a cabinet for drawers, while also allowing easy removal of the storage boxes. I use the rack to store many small parts for 3D printing and electronics.

Figure 1 - Modular Storage Rack

These include screws, nuts, bolts, wires, and various electronic components. The easy removal of the boxes allows for quick access to parts while working on projects. I also wanted the storage system to be highly visual, as that helps me locate parts.

Figure 2 - Modular Storage Rack, CAD Layout

I wanted to explore plastic design for manufacturability, so I set out to create a storage system that uses no fasteners and could be mass-produced through conventional injection moulding. This involved trialing different tolerances on plastic clips and joints, and exploring the use of different plastics, as the most common PLA is too stiff and brittle for snap-fit joints. ABS was tried, although it had a tendency to delaminate even when the extrusion head and 3D printer bed were very hot.

Finally, ASA was selected as it provided both strength and flexibility, did not delaminate, and adhered to the bed far better than ABS. Many lessons were learned in controlling the 3D printing process, and ASA has become my go-to plastic for functional prototypes.

One of the main challenges was developing a reliable method for joining the two plates. After several iterations and tolerance adjustments, I settled on a tongue-and-groove connection with an integrated clip mechanism to hold the plates together. This design proved to be both strong and easy to assemble; the joint is shown in Figure 3 with the final CAD design assemble in Figure 2.

Figure 3 - Tongue and Groove Joint Detail