Bento Box

a simple lunch box for easy to-go

Stanford University, ME103: Product Realization: Design and Making, 9 week individual project

The Problem

Even though there are compost bins scattered around campus, many of the eateries at Stanford still use plastic packaging. I wanted to make a reusable container that would easily fit in my backpack to use instead of the plastic to-go boxes when I want to escape from the dining hall food.

Rapid Prototype

My initial idea was to have two stacking boxes that could be collapsed down when there’s no food, but expanded to fit more food if I needed it.

Initial CAD

I decided to make rounded corners rather than a rectangle in order to make the bento box more safe to put in bags. I then created a CAD model and scaled it down to test the assembly and fit.

The Master Plan

After making the CAD and prototype, it was time to plan out exactly how I was going to make the box. Around the same time, I was already practicing TIG welding aluminum, and I quickly realized that it would be too much work to weld two boxes plus the lid, so I refined my scope and decided on a single box and lid.

Practice, Practice, and more Practice

Before welding my final bento box, I first had to learn to TIG weld aluminum. This was by far the most time consuming part of the project, and I greatly underestimated how hard it is to weld aluminum compared to steel. After around 30 hours of practice, I was finally able to weld both butt welds and corner welds. While it was frustrating around hour 12 not seeing progress, in the end it was definitely a rewarding experience.

The Final Welds

After I was able to weld my practice corners consistently, it was time to do the actual box. This was super nerve wracking because there was only one chance, and if I messed up any of the welds I would have to start over. But in the end, it was a success!

Sanding and Finishing

After welding, all that was left was to smooth out the welds and buff out any scratches. I also used the mill to sand down the edges of the lid and box in order to get rid of any notches that were left over from welding imperfections, and from there it was lots of work on the sander to get nice, smooth corners. For the inside corners, I used sandpaper wrapped around a Dremel tool. Because of the COVID-19 pandemic, my sanding time got cut short, but even without finishing the box is still functional!

The Bento Box

Even though my project was cut a little short by COVID, I was still able to make a great box that is both functional and sleek! With a little more sanding as well as a silicone mold in the lid to seal it completely, this will be the perfect bento box to slip into my backpack and take food to go.