Prototyping and Modelmaking for Product Design

At an industrial design firm, two new concepts for a handheld medical scanner are presented. The first is a stunning, photorealistic 3D rendering on a massive 8K screen. The team marvels at its sleek curves, the perfect simulated reflections on its screen, the precise way light catches its textured grip. The second concept is a block of high-density foam, roughly carved and spray-painted gray, with a few buttons glued on. It feels awkward, unbalanced. A senior engineer picks it up, her thumb naturally searching for a grip point that isn’t there. She notes the weight distribution is all wrong; it would cause wrist strain within minutes. A nurse on the review panel points out that a crucial button is impossible to press while holding the device securely. The beautiful digital image offered a flawless vision, but the clumsy foam block offered immediate, undeniable truth.

This gap—between how an idea looks and how it actually feels and functions in the human hand—is where countless brilliant concepts fail. It’s a challenge that fascinated Bjarki Hallgrimsson throughout his career. As a practicing industrial designer and later as a professor, he saw generations of students fall in love with their digital drawings, only to be confronted by the harsh, unyielding realities of ergonomics, materials, and manufacturing when it was often too late. He wrote this book as a practical guide to the messy, hands-on, and indispensable process of discovery that happens when you build things. It's a codification of the workshop wisdom that turns a beautiful picture into a genuinely useful object.

Module 1: Prototyping as a Problem-Solving Discipline

Many teams treat prototyping as a single, late-stage step. A final check before production. Hallgrimsson argues this is a huge mistake. Instead, prototyping is a continuous, iterative problem-solving activity. It's a mindset that should run through the entire development cycle. The goal is to reduce guesswork and kill bad ideas early. A physical model forces your team to confront reality. Abstract debates in a conference room can go on forever. But when you put a tangible object on the table, the conversation changes. It becomes grounded, focused, and productive. The Fiskars Multi-Snip pruning tool, for instance, went through many physical iterations. Each model solved a specific problem, refining the ergonomics and mechanics long before any expensive tooling was created.

From this foundation, we see that prototyping is not one-size-fits-all. Different questions require different tools. This leads to a crucial insight: physical and digital prototypes are complementary, not competitive. Digital tools like CAD are fantastic for visualization. They can simulate weight, analyze assembly, and run performance tests. But they can’t tell you how a product feels. For that, you need a physical object. The development of a Fiskar’s post-digging tool started with a handmade prototype. The team needed to evaluate its physical handling and balance. Only after they validated the core ergonomics did they move to a detailed 3D computer model for technical analysis. This blended workflow is far more powerful than relying on one method alone.

So what happens next? This hands-on process builds something more valuable than just a model. It builds intuition. Modelmaking is a foundational "learning-by-doing" activity that builds a designer's sensibility. When you physically shape a material, you have a conversation with it. You learn its limits, its strengths, and its potential. This direct, sensory experience is something you can't get from a screen. It’s how designers at Duo Gaming developed their controllers. They hand-carved dozens of foam models, literally designing "by the hand for the hand." This deep, tactile understanding informed better conceptual decisions and allowed them to fail safely and cheaply in the early, exploratory stages.