Chavant Contour S® – Sulfur-Free Modeling Clay for Sculpting & Silicone Mouldmaking

Premium Sulfur-Free Modeling Clay for Professional Sculpting and Mouldmaking Applications

Chavant Contour S is a sulfur-free, non-hardening modeling clay with a buttery smooth hand feel in the soft (Soft) grade. The clay shapes, scrapes and cuts smoothly and holds exceptionally fine surface detail. With a durometer of 19 Shore A, this is the softest variant in the Contour series, ideal for fine modeling work at room temperature (around 23 °C). The warm gray color makes profiles and surface textures clearly visible while sculpting. Contour S is sulfur-free and therefore safe to use in combination with silicone rubber, without inhibiting the cure of the mould.

Because Contour S does not harden, the clay remains reusable indefinitely. At room temperature the clay is firm and dimensionally stable; when warmed it becomes soft, spreadable or even brushable, after which it returns to its original firmness on cooling.

Key Benefits

• Sulfur-free – safely combined with platinum and condensation silicones for mouldmaking, without cure inhibition.
• Durometer 19 Shore A – the softest Contour variant, for smooth sculpting and fine detail work.
• Buttery smooth hand feel – comparable to sulfur-based clay, but silicone-friendly.
• High temperature resistance – only softens from 57 °C and holds its shape in warm studio environments.
• Solvent-friendly – surface can be smoothed and dissolved with naphtha, mineral spirits or 99% isopropyl alcohol.
• Reusable – does not harden and retains its properties after reheating.

Typical Applications

• Figurative and industrial sculpting, from miniatures to monumental work.
• Master models for moulding with silicone rubber.
• Prototyping and design models where fine detail matters.
• Troweling onto EPS foam and mixed-material armatures as a shapeable coating.
• Brushable build-up of thin layers on armatures after warming.
• Restoration and reproduction work requiring reworkability.

Processing Instructions

1. Build an armature if needed; Contour S is not self-supporting for figurative work.
2. Sculpt at room temperature (around 23 °C) for the finest detail; use traditional wood, plastic, metal or silicone tools.
3. Warm to around 57 °C to soften the clay; to 77 °C to trowel it with a metal spreader; to 85 °C to make it brushable.
4. Use a temperature-controlled slow cooker, laboratory oven or warming box. Do NOT use a microwave (uneven heating) or a household oven.
5. Smooth the surface with clay scrapers or rake tools; finish with naphtha, mineral spirits or 99% isopropyl alcohol.
6. Clean tools and surfaces with naphtha or 99% isopropyl alcohol.

Important When Moulding with Silicone Rubber

Avoid citrus-based solvents such as D-limonene on the clay surface when moulding with silicone rubber: these can inhibit the cure of the silicone. In that case use naphtha, mineral spirits or isopropyl alcohol. Do not use isopropyl myristate, because the surface will then remain permanently soft and will not return to its original hardness.

Chavant is a leading American manufacturer of professional modeling clay for sculptors, model makers and the moulding industry.

Professional Support

Not sure whether Contour S is the right hardness for your sculpting or mouldmaking project? Feel free to contact Silicones and More; we are happy to advise on the right clay and compatible silicones for your application.