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THE CLAY MODELING METHOD IN AUTOMOTIVE DESIGN
Ergashev Dostonbek Pratovich
Assistant, Andijan State Technical Institute
Abstract:
Clay modeling remains a fundamental technique in the automotive design process,
serving as a critical bridge between conceptual sketches and production-ready prototypes.
Despite advances in computer-aided design (CAD) and virtual reality (VR), clay models provide
tangible, full-scale representations of vehicle concepts. This paper explores the methodology,
tools, materials, and stages of clay modeling in the automotive industry, highlighting its role in
design iteration, ergonomic validation, and surface quality assessment. Case studies and expert
interviews reinforce the method’s continued relevance in both traditional OEMs and modern
design studios.
Keywords:
Clay modeling, automotive design, physical prototyping, surface modeling, design
validation, CAD integration
1. Introduction.
The automotive industry continually seeks innovation in aesthetics, aerodynamics, and user
experience. While digital design tools have revolutionized the early phases of concept
development, clay modeling endures as an irreplaceable step for tangible evaluation. Clay
models enable designers and engineers to examine surface flow, proportions, and user interaction
at 1:1 scale, offering real-world feedback that digital screens cannot replicate.
Historically, car manufacturers began using industrial clay in the 1930s, and since then, the
process has evolved with more precise tools and hybrid workflows combining digital and
physical media. Today, even electric vehicle (EV) startups like Lucid Motors and Rivian utilize
clay to finalize their exterior and interior designs. This paper systematically examines the stages
of clay modeling and how it complements digital methods.
2. Methods
2.1. Tools and Materials UsedClay modeling uses industrial-grade modeling clay composed of
wax, oil, and filler. The clay is pliable when warm and hardens at room temperature, making it
suitable for sculpting and milling. Common tools include:
Clay loop tools (metal blades for shaping)
Surform tools (for smoothing surfaces)
Wire cutters and calibration sticks
Temperature-controlled ovens to soften clay
CNC clay milling machines for precision shaping
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Image 1 – Typical clay modeling tools
2.2. Stages of Clay ModelingThe process typically includes the following phases:
Armature Construction: A steel or aluminum substructure is built to support the clay and mimic
the car’s chassis. Foam blocks are often added to fill volume.
Clay Application: Heated clay is layered onto the armature to build a rough shape.
Rough Shaping: Designers use manual tools to approximate the form based on CAD references.
Surface Refinement: Skilled sculptors refine curves and panel transitions.
Symmetry Milling: Half of the model is digitized and mirrored using a CNC milling machine.
Surface Finishing: Surfaces are smoothed with alcohol-based solutions and wrapped in reflective
foil to assess design under studio lighting.
Image 2 – Clay modeling in automotive design
2.3. Digital Integration
The hybrid workflow includes 3D scanning of the clay model for digital iteration. Surface data is
re-imported into CAD tools like Alias or CATIA for aerodynamic analysis and tooling
preparation.
3. Results
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3.1. Design Accuracy and Tactile Feedback
Clay modeling enables high surface fidelity and real-time designer interaction. Unlike screen-
based modeling, clay surfaces can be touched, viewed under changing lighting, and physically
critiqued from all angles.
Table 1 – Comparison of CAD vs Clay Model Capabilities
Parameter
CAD Modeling
Clay Modeling
Tactile Evaluation
✖
✔
Lighting Behavior Limited (simulated) Real-world
Team Interaction
Virtual
Physical, real-time
Cost Efficiency
High (no materials) Medium
Surface Precision Very high
High
3.2. Ergonomic and UX Validation
Interior clay bucks are used to test driver reach, seat positioning, and instrument visibility.
Stakeholders, including non-engineers, can engage directly with clay models to give feedback.
Image 3 – Interior Clay Model Used for Ergonomic Testing
3.3. Marketing and Decision Making
Executives and clients often prefer clay models for milestone reviews. Their realism and visual
clarity make them powerful tools for approving or rejecting design directions.
3.4. Time and Cost Considerations
A full-scale exterior clay model typically takes 2–3 weeks and costs $60,000–$100,000,
depending on complexity. However, it reduces costly mistakes before tooling and production.
4. DiscussionDespite the rise of virtual prototyping, clay modeling retains its relevance due to its
physical immediacy and intuitive design communication. Designers often report that clay
“reveals” problems that screens don’t show—such as subtle distortions in panel reflections or
uneven transitions.
Hybrid processes are now the norm: design teams often begin with digital sketches, 3D print
scaled models, then move to clay for 1:1 reviews. CNC milling further enhances accuracy,
allowing quick updates and real-time feedback.
Automotive schools, such as ArtCenter College of Design and Umeå Institute of Design,
continue to teach clay modeling as a core skill. This demonstrates its importance in the training
of the next generation of automotive designers.
Furthermore, as sustainability becomes a key concern, many studios now recycle clay material
and use renewable-sourced tooling structures.
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5. ConclusionClay modeling remains a cornerstone of the automotive design process. Its ability
to bring digital concepts into the physical world enables better decision-making, design
evaluation, and human-centered engineering. While digital tools accelerate early development,
clay provides the final step of verification before mass production.
For design teams striving to combine aesthetics, functionality, and manufacturability, clay
modeling delivers unmatched spatial accuracy and collaborative power. In the foreseeable future,
its role will remain vital alongside evolving digital technologies.
References
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2. Rattenbury, K. Automotive Clay: A Sculptor's Perspective // Car Design Quarterly. - 2021. -
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3. Bangle, C. Physical Form and Design Interpretation. – Journal of Automotive Design. -
2019. - Vol. 7, No. 3. – P. 88–102.
4. Autodesk. Digital Clay Workflow with Alias AutoStudio. – Autodesk White Paper, 2022.
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