Security at Scale – Creating a Miniature Circular Vault

For my main project I will be creating a safe with a circular vault door at 1/12 (dollhouse) scale. Growing up in Delaware, there was not much to do so I would often visit Philadelphia for its culture and history. The city of Philadelphia is the birthplace of banking in the United States of America, with the first commercial bank in the newly formed United States being created in this city in 1782 [1].

The history of banking is deeply intertwined with both architectural and technical innovation. To instill confidence in their security, banks have historically projected an image of grandeur and strength. In the early 1800s, many banks adopted Greek Revival architecture, characterized by imposing stone structures and large marble columns—an aesthetic that remains iconic today. Many historic bank buildings in colonial cities continue to serve their original purpose.

One of my earliest exposures to this architectural style was the Sussex Trust Building in Lewes, Delaware (Figure 1). Although the Sussex Trust Company ceased operations following a merger in the 1990s, the building still functions as a bank under M&T Bank. However, as bank robberies became more prevalent, architectural design alone was insufficient to assure customers of their money’s security. This necessity led to the widespread implementation of vaults—integral to both the physical and psychological security of banking institutions.

Figure 1. Sussex Trust Company building in Lewes, Delaware in modern times.

Vaults are an engineering marvel, seamlessly combining civil and mechanical engineering to create secure, impenetrable rooms within a building. I have always been fascinated by complex mechanisms, and vault doors are no exception. My favorite vault design features circular doors with intricate gear systems that drive locking pins, securing a thick steel plate over the entrance, such as the vault door shown in figure 2. These designs exemplify both strength and precision, instilling trust in users through their sheer engineering excellence.

Figure 2. Circular vault door at Winona National Bank built in the early 1900s [2].

I recently saw a video from Adam Savage’s YouTube channel Tested in which he builds his own miniature vault and it is the direct inspiration for this project [3]. I will use this four-part video series as a loose guide for my build. This project will challenge my CAD skills, mechanical expertise, and ability to work at a model scale. My design will emphasize an industrial aesthetic, highlighting the intricate engineering behind these remarkable structures. I will design and construct my own gearing and rack-and-pinion system to drive the locking pins that secure the vault door. Additionally, I will weld a safe to attach the door to, striving to match the aesthetic shown in figure 3.

Figure 3. Circular vault door model designed and built by Adam Savage.

The focus of this project is to highlight the beauty of mechanical systems by creating a functional and visually striking artifact. It will challenge my ability to design complex mechanisms in 3D CAD software while also refining my metal fabrication skills. As welding is a new skill I am learning, this project will provide an opportunity to practice creating precise geometric shapes using sheet metal and welding techniques.

References

1. https://philadelphiaencyclopedia.org/essays/banking/
2. https://en.wikipedia.org/wiki/Bank_vault
3. https://www.youtube.com/watch?v=SiL8IzJSnyU

Images

1. https://upload.wikimedia.org/wikipedia/commons/thumb/2/2a/Sussex_Trust_Company.jpg/1200px-Sussex_Trust_Company.jpg?20210918103818
2. https://en.wikipedia.org/wiki/File:WinonaSavingsBankVault.JPG
3. https://pbs.twimg.com/media/GP6Bm-mXQAAjky5.jpg:large

This post was edited for clarity and conciseness using ChatGPT.