Clay modelling in automotive design: what it is and why do automakers still use it

There's a fascinating paradox at the heart of brands like BMW, Ferrari, and Porsche: the same companies that develop some of the most advanced 3D modeling software on the planet continue to use clay to design cars. Not as a nostalgic legacy or tradition, but as a central and irreplaceable part of the design process. For those who want to understand what clay modelling is in automotive design, this paradox is the most honest starting point.

This article explains what this technique is, why it resists digital advancement, how the process works in practice, and what a young person produces when they have contact with clay modelling in a real training program.

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What is clay modelling in automotive design?

Clay modelling, or clay modeling, is the technique of constructing three-dimensional physical models of vehicles using industrial clay. The material used is not ordinary clay for manual arts: it is a substance called Industrial Plasticine, with a specific composition of calcium sulfate, waxes and mineral fillers.

This clay has unique properties:

• It is solid at room temperature (around 25°C)
• It is malleable when heated to approximately 60°C
• Can be added, removed, and refined with specific tools
• Accepts surface finish that simulates metal or paint
• It does not dry or crack, allowing long-lasting work on the same model

The models are built on internal foam or wood structures, which form the approximate volume of the vehicle. The clay is then applied in layers and worked with tools called rakes and scrapers until it reaches the desired surfaces and curvatures.

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Why do BMW, Porsche, Ferrari, and Lamborghini still use clay if advanced 3D software exists?

That's the question any reasonable person would ask. The answer lies in the difference between visual perception on the screen and sensory perception in the physical world.

The problem with digital surfaces

Software such as Autodesk Alias and ICEM Surf are powerful tools for surface modeling. They allow you to create shapes with millimeter precision and visualize them with simulated light. However, simulated light doesn't behave exactly like real light.

The curvature of a car is assessed by designers by the way light glides over surfaces. A curvature variation of tenths of a millimeter, invisible on any high-resolution screen, is immediately noticeable when a designer looks at a physical model illuminated by real directional light.

BMW designers explain this principle directly: the two-dimensional screen compresses volume information. The clay model places the object in space, with real reflections, real shadows, and aspect ratios that the human eye processes completely differently than on any monitor.

The perception of volume and scale

1. A 1:4 scale model allows the designer to step back and evaluate the vehicle's silhouette as the outside observer will see it
2. Minor imperfections in the transition between surfaces are evident in low light, something that digital rendering tends to soften
3. The relationship between different volumes, such as hood, sides, and rear, can be intuitively assessed when moving around the model
4. The designer's human scale in relation to the model communicates information about proportion that does not exist when interacting with a screen

Brands such as Porsche and Ferrari have publicly documented that the clay model is a mandatory part of any series project. Lamborghini maintains a dedicated team of clay modellers at its Centro Stile in Sant'Agata Bolognese. The process isn't optional, even in 2026.

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How does the clay modelling process work in practice?

What tools are used?

Working with industrial clay uses a specific set of instruments:

• Rakes: cut-out profile tools used to remove clay and create flat or slightly curved surfaces
• Scrapers: flexible blades for smoothing and refining surfaces after initial modeling
• Profile gauges: cross section verification templates to ensure symmetry between the two sides of the model
• Heat guns: hot air guns to soften clay locally and allow work in specific areas

The process of adding and removing clay is continuous. An experienced clay modeller constantly alternates between the two operations, refining the shape by progressive approximation until it reaches the surfaces specified in the digital reference file.

From sketch to clay: what is the sequence of work like?

Clay modelling doesn't happen in isolation. It's part of a sequence:

1. The designer produces hand sketches and digital concept renders
2. The most promising sketches became digital models in surface software
3. The digital model is printed or milled on foam as the base structure
4. The clay is applied over the structure and worked until it reaches the surfaces of the digital model
5. The physical model is evaluated in directional light for surface verification
6. Adjustments are made directly on the clay and then scanned back into the software

This cycle is repeated several times during the development of a project. The versions range from 1:10 scale models for concept studies to full-scale models for final approval. A full-scale model of a sedan is approximately 4.5 meters long and can weigh more than half a ton, including the internal structure.

For those who want to understand the full career surrounding this technique, the article on Career in automotive design explains what a car designer does on a daily basis, where they work and what specializations are in the field.

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What is a clay modeller and what is their role on the design team?

Clay modeller is the professional specialized in constructing and refining physical clay models within an automotive design center. It is a highly specialized technical function, distinct from the designer who conceives the form.

The clay modeller:

• Interprets digital data and translates it into physical form with precision
• He knows the properties of the material in depth and knows how to work it under different conditions
• Collaborates directly with the designer for surface adjustments that were not digitally specified
• Uses measurement equipment such as 3D scanners to verify the fidelity of the model to the reference file

In the largest automakers, it is a specialized technical career, generally linked to internal training programs. In smaller design centers and independent studios, the designer often accumulates knowledge of clay modelling as part of the technical repertoire.

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What does a young person learn by practicing clay modeling in an intensive program?

Why is learning clay modelling before university a real differential?

The portfolio required by the best automotive design universities, such as the Politecnico di Milano, IED Torino, and the Royal College of Art, includes projects that demonstrate technical mastery of the tools in the area. Clay modelling is one of those tools.

A candidate who comes to the selection process with sketches, a finished digital rendering, and a 1:10 physical clay model demonstrates something that few candidates are able to show: real contact with the industry's professional techniques. This is verifiable and concrete, and the evaluators of the best schools know how to distinguish work produced in a professional context from work produced in a generic school context.

In an automotive design program in Italy, such as the one offered by Be Easy, students aged 15 to 18 go through the following sequence in the clay module:

• Knowledge of the material: properties, heating, behavior at different temperatures
• Construction of the base structure in foam on a workbench
• Application of the first layers of clay and definition of general volumes
• I work with rakes to create the main surfaces
• Refinement with scrapers and light analysis with directional lighting
• Delivery of the finalized 1:10 model as part of the portfolio

The physical process of building a model with your own hands produces an understanding of form and volume that no software reproduces. Young people who have experienced this contact report a change in the way they see car surfaces, even after returning home.

To understand the full context of an intensive automotive design program in Italy, the article on automotive design summer camp in Italy details what is taught week by week and how to assess whether a program is serious.

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Frequently Asked Questions About Clay Modelling in Automotive Design

What is Industrial Plasticine and why is it different from ordinary clay?Industrial Plasticine is a technical clay composed of calcium sulfate, waxes and mineral fillers. Unlike ordinary clay, it does not dry out, does not crack and can be worked indefinitely. Its consistency is controlled by temperature, which allows for both removal and addition of material in a precise manner.

What is the difference between a 1:10 clay model and a full-scale one?The 1:10 models are used for concept studies and analysis of overall silhouette and proportions. Full-scale models allow detailed evaluation of surfaces, verification of how light falls on each curve, and ergonomic analysis with respect to the real user. Large-scale automakers use both throughout the process.

Will clay modelling be replaced by 3D printing?3D printing is already used for prototyping parts and detail elements. For body surfaces, clay is still preferred because it allows direct and immediate intervention by the designer, without the file-printing-verification cycle. The ability to modify the surface on the same model, in real time, is an advantage that printing does not replate.

Can a young person with no previous experience learn clay modelling in 2 weeks?Yes, especially at the level of a 1:10 model. The goal is not professional mastery, but real contact with the material, tools, and process. This contact is already sufficient to produce a portfolio deliverable and, above all, to create a practical understanding of volume and surface that does not exist without physical work.

Is clay modelling taught at automotive design universities?Yes, it is part of the curriculum of the main universities in the area, such as IED Torino, Politecnico di Milano and Domus Academy. Access to the technique before graduation, in a professional context such as an intensive program in Italy, positions the candidate at an advantage in the selection processes of these institutions.

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Be Easy

Be Easy offers the Automotive Design & Future Mobility program for young people aged 15 to 18 in Milan, which includes a complete clay modeling module with industrial clay, professional tools and real workbenches. The student comes out with a 1:10 physical model as part of the portfolio, in addition to sketches and digital rendering. To learn more about dates and registration process, contact us.