Things designers need to know about sheet metal prototyping

Diving into sheet metal fabrication might initially appear daunting for a product designer, but understanding this industry is essential given its significant market presence. In 2018, the global market for sheet metal fabrication reached $265 billion and is projected to grow at a CAGR of 5% from 2019 to 2025. For those involved in product development, sheet metal prototyping not only offers an introduction to consumer products but also serves as a crucial testbed for design practices that affect the usability and feasibility of the final product.

The first step in sheet metal prototyping involves working with a third-party fabrication shop, which presents an opportunity to refine a design’s practical aspects and potential challenges. Whether you are a seasoned designer or new to the nuances of metal structures, choosing a skilled fabrication partner can significantly impact the success of a project. This collaboration allows for the real-world application of theoretical designs, ensuring that the fabricated prototype aligns with product development goals.

For product designers, it is fundamental to master the thickness requirements of sheet metals, which typically range from 0.006in to 0.25in thick. Materials thicker than this are considered metal plates, while those thinner are categorised as foils or leaf metals. This distinction is significant to avoid common misclassifications that can lead to design flaws or fabrication errors.

Exploring sheet metal fabrication processes
Sheet metal fabrication is a versatile field involving various processes like cutting, deformation, and assembly, where flat metal pieces are transformed into complex structures or functional products. Understanding these processes is vital for designers to conceive and execute designs that are not only innovative but also manufacturable.

Sheet metal prototyping provides a tangible way to refine design concepts through physical models and prototypes. This stage is critical in eliminating guesswork in manufacturing, allowing designers to test performance, identify flaws, and minimise costs by addressing issues before full-scale production begins. Although the initial investment in prototype fabrication might seem high, its value in preventing expensive revisions during batch manufacturing is undeniable. This proactive approach ensures that products meet stringent quality standards from the beginning.

Selecting appropriate engineering materials for sheet metal prototypes is crucial to match the end-use properties and requirements of the final product. Metals like aluminum, stainless steel, copper, and magnesium offer various benefits, including lightweight properties, strength, thermal resistance, and corrosion resistance. Factors such as machinability, surface finishes, and durability are also important to minimize fabrication risks and optimise performance. For example, aluminium is favoured for its low density and high flammability resistance, making it suitable for a wide range of applications.

Best design practices for sheet metal prototypes
Effective design practices for fabricating sheet metal prototypes are essential to balance manufacturing costs and lead times. Ensuring that holes have a diameter no less than the thickness of the sheet metal is crucial to prevent tool breakage or metal damage. Additionally, maintaining accurate tolerances and keeping features simple are key strategies to facilitate smoother fabrication processes. When incorporating bends, choosing a radius that complements the material thickness can reduce manufacturing difficulties. For complex designs, outsourcing to a reputable fabrication shop can be a wise decision to ensure high-quality outcomes.

In summary, mastering sheet metal fabrication involves understanding material specifics, fabrication processes, and design best practices. By engaging with skilled fabricators and leveraging the right materials and techniques, designers can ensure their prototypes are both practical and aligned with their development goals.

Other crucial manufacturing techniques that product designers should explore, include injection moulding process, CNC prototyping, and injection moulding service to further enhance your design capabilities.