Chavant Hard Clayette is a high-hardness professional sculpting clay formulated without sulfur compounds, making it fully compatible with platinum silicones with no risk of inhibition. With its characteristic non-tacky surface and exceptional tool response, it is the go-to choice for sculptors, modelmakers and special effects professionals who need maximum detail, precision and dimensional stability in their pieces.
Technical specifications
| Property |
Value |
| Presentation |
Individually wrapped 906 g block |
| Color |
Bone white / beige |
| Hardness |
High (Hard) |
| Sulfur-free |
Yes — no sulfur compounds |
| Toxicity |
Non-toxic |
| Odor |
No appreciable odor |
| Surface |
Non-tacky |
| Working temperature |
Room temperature (can be gently warmed to soften) |
| Reusable |
Yes — can be heated and cooled repeatedly |
| Air stability |
Does not oxidize — can be left exposed between sessions |
What it is used for
Chavant Hard is designed for applications that demand high definition detail and strong dimensional stability. Its hardness makes it the ideal tool for precision work where the clay must resist the sculptor's pressure without deforming or losing shape between sessions:
- Character sculpting with fine detail: skin textures, clothing, ornamental work and complex reliefs
- Industrial and product prototyping where stable form and sharp edges are required
- Creating masters for molding with platinum silicones with no risk of inhibition
- Architectural scale models and product design models
- Special effects (FX) for film, television and theater: prosthetics, creatures and props
- Sculpting heads, busts and large-format figures requiring multiple work sessions
- Any application where a reusable, long-lasting master is needed
How to use it
- Condition the material: at room temperature Chavant Hard is firm. If you need greater workability to start, warm it gently with a heat gun or in a low-temperature oven (do not exceed 60–70 °C) until it reaches a workable consistency.
- Build the base volume: add blocks and strips of clay over your armature or support. Press firmly to ensure adhesion between layers and avoid internal voids.
- Sculpt with tools: once at temperature, work with spatulas, styluses and rakes to define planes and general forms. The hardness of the material gives you full control over your strokes.
- Refine the detail: as the material cools back to room temperature it regains its hardness, making fine detail work easier without distorting areas already sculpted.
- Smooth the surface if needed: you can gently run a cloth or warmed metal spatula over the surface to unify it before molding.
- Prepare for molding: being sulfur-free, you can pour platinum silicones directly over the sculpture without applying any special release agent, although it is always advisable to carry out a prior inhibition test on a small area.
- Reuse the material: after demolding, collect the Chavant Hard remnants, warm them up and use them again with no loss of properties.
Tips and techniques
Temperature control for different stages of work
Temperature is your primary control tool with Chavant Hard. For initial volume work, slight warming facilitates layer adhesion. For fine detail, always work with the material at room temperature or even slightly cool: the extra hardness gives you more precise strokes and cleaner edges. In summer or in warm studios, you can briefly cool the piece to recover hardness before working on delicate areas.
Compatibility with platinum silicones
One of the key advantages of Chavant Hard is its sulfur-free formulation. This sets it apart from other industrial clays with vegetable bases or sulfurous oils that inhibit the curing of addition (platinum) silicones. Even so, if you have handled other materials in the same workspace (latex, fresh epoxy, other adhesives), wash your hands before touching the silicone and always perform a small inhibition test on one end of the sculpture before molding the complete piece.
Storage and reuse
Chavant Hard does not dry out or oxidize in air, so you can leave the sculpture exposed between sessions without any problem. To store offcuts or finished pieces long-term, simply wrap them in paper or film to prevent dust buildup. The material can be heated and reused indefinitely: collect all trimmings and remnants from the process, melt them together and you will have a block ready for the next piece.
Frequently asked questions
What is the difference between a hard clay and a medium-hardness clay?
Hardness determines how much resistance the material offers to tool pressure. A hard clay like Chavant Hard holds details with greater precision and does not deform when you rest your hand on the piece, making it ideal for fine detail and precision work. Chavant Medium is softer and responds better for quick volume work or for those looking for easier modeling at room temperature.
Does this clay inhibit platinum silicones?
No. Chavant Hard is formulated without sulfur compounds, which are the main cause of inhibition in platinum silicones. You can mold directly over it with addition silicones. As an additional precaution, always perform a small inhibition test before molding the complete piece, especially if other sensitive materials such as latex, fresh epoxy or cyanoacrylate adhesives have been used in the workshop.
How do you soften it for working?
You can soften it with a heat gun applied directly to the area you want to work on, or by warming the entire block in a low-temperature oven (do not exceed 60–70 °C). Once it reaches the right temperature it becomes easily moldable. As it cools it regains its original hardness without losing any properties.
Can it be reused after molding?
Yes, this is one of its main economic advantages. After demolding, collect all the Chavant Hard remnants, warm them and blend them back together. The material does not lose properties through heating and cooling cycles, so it can be reused indefinitely.
How much material do I need to sculpt a full head and bust?
For a life-size head with part of the bust up to the shoulders, between 4 and 6 kg of material is typically needed, depending on wall thickness and the armature system used. With Chavant Hard in 906 g blocks, count on at least 5–6 units for a piece of that scale when working over an internal armature.
Can the sculpture be painted or sealed before molding?
In most cases it is not necessary to seal the Chavant Hard surface before molding with platinum silicone, as the material is non-porous and contains no inhibiting substances. If you want to apply a surface finishing coat (for example, for solvent smoothing), always use products compatible with platinum silicones and allow them to evaporate completely before molding.
Is it suitable for use with children or in educational settings?
Chavant Hard is non-toxic and odorless, but it is conceived as a professional working tool. Its high hardness makes it poorly suited for children's use without prior warming. For professional-level educational settings (art, design or FX schools) it is perfectly valid and safe when following the usage instructions.
How does it differ from an industrial vegetable-based clay?
Industrial vegetable-based clays, such as the Vegetable-Based Industrial Clay from Feroca, are intended for general modeling and may contain traces of sulfur compounds that inhibit platinum silicones. Chavant Hard is expressly formulated for professional use in sculpture and FX, with guaranteed absence of sulfur, better detail response and more consistent batch-to-batch performance.
