Monster Clay Green Medium is a professional oil-based modelling clay, sulphur-free and formulated with non-toxic, food-safe components. Its medium hardness offers the ideal balance between workability and detail retention, and being fully reusable and re-meltable, it is a long-term studio tool for both organic sculpture and industrial prototyping or special effects.
Technical specifications
| Parameter |
Value |
| Colour | Green |
| Hardness | Medium |
| Base | Oil-based |
| Sulphur content | Sulphur-free |
| Toxicity | Non-toxic — food-safe components |
| Net weight per unit | 2.05 kg (4.5 lb) |
| Container | Microwave and oven safe (up to 250 °C) |
| Reusable | Yes, indefinitely |
| Platinum silicone compatibility | Compatible (sulphur-free) |
| Tack | Low — does not stick to tools or fingers |
What it is used for
Monster Clay Green Medium is designed for professionals and semi-professionals who need a reliable modelling material with excellent detail definition and direct compatibility with the most common moulding systems. Its medium hardness makes it suitable for both organic sculptures and industrial or special effects pieces, and its green colour makes it easier to visualise light and shadow planes during modelling.
- Character sculpting, busts and life-size figures for special effects (SFX) and film
- Industrial prototyping and mock-ups where continuous review and modification is required
- Creation of masters for subsequent moulding with platinum silicone or polyurethane
- Modelling of prosthetics and FX elements intended to be replicated in flexible materials
- Corrections and adjustments to sculptures in progress without having to redo the entire piece
- Advanced training and practice in modelling and Mold Making workshops
How to use it
- Soften the material: remove the required amount from the container and heat it gradually in the microwave in short intervals of 10–15 seconds, or in the oven at low temperature (do not exceed 250 °C). Work in small portions for even heating.
- Condition it with your hands: once warm, knead it briefly until you achieve a uniform, homogeneous texture. At room temperature it is firm; heat makes it more fluid and easier to sculpt.
- Build the base shape: apply successive layers over an internal armature (wire, foam, plaster base) or directly onto the work surface. The low tack makes it easy to handle with modelling tools and spatulas.
- Refine the detail: use fine-tipped tools to add textures, lines and details. To smooth surfaces, gently apply localised heat with a heat gun or pass a slightly warmed tool over the area.
- Check the sculpture: verify proportions and symmetry from different angles before proceeding to moulding. Monster Clay can be modified as many times as necessary.
- Prepare for the mould: make sure the sculpture is at room temperature and firm before applying silicone or any other moulding material. Being sulphur-free, it is directly compatible with platinum silicones without any prior sealing.
- Recover leftover material: scraps and off-cuts can be re-melted and reused without any loss of properties.
Usage tips
Working temperature control
Monster Clay Green Medium changes noticeably in consistency with temperature. In a cold studio (below 18 °C) it is advisable to heat it a little more before sculpting. In summer or in warm studios it may be softer than usual; in that case, work in small portions and let them cool for a few minutes on a cold surface (marble, glass) before adding fine detail. A heat gun set to a low temperature is ideal for softening specific areas without affecting the rest of the sculpture.
Combining hardnesses for greater versatility
Many professionals combine different Monster Clay hardnesses in the same piece: a hard hardness base (such as Chavant Hard) for the internal structure, and the Medium for the detail layers. You can also mix Monster Clay Medium with a softer hardness to obtain a custom softness transition. The different grades are miscible with each other.
Cleaning tools and surfaces
Tools are easily cleaned with a cloth and a little isopropyl myristate, which dissolves clay residue without damaging metals or wood. Avoid aggressive solvents that may leave inhibiting residues if the same tool is to be used afterwards in contact with platinum silicones. Store Monster Clay in its original container, tightly closed, when not in use, away from direct heat sources.
Frequently asked questions
What hardness of modelling clay should I choose if I am starting out?
It depends on the level of detail you are after and your technique. Medium hardness, like Monster Clay Green Medium, is the most versatile option for those who are learning: it allows you to build large shapes and add fine detail without requiring much force. Higher hardnesses demand more experience but offer greater precision on very fine details. If you are just starting out, medium is the recommended starting point.
Can I use this clay directly to make a platinum silicone mould?
Yes. Monster Clay Green Medium is formulated without sulphur, making it directly compatible with platinum (addition-cure) silicones without the need to apply a sealer beforehand. Make sure the sculpture is at room temperature and free of contaminants before pouring the silicone.
Does the clay harden over time or dry out?
No. Monster Clay Green Medium does not dry out or set in air. It retains its properties indefinitely when stored correctly in its closed container, away from continuous heat sources. This sets it apart from polymer clays, which require baking to harden.
How do you heat it correctly to soften it?
The most common method is the microwave: intervals of 10–15 seconds at medium power, checking the texture between each cycle. You can also use a conventional oven at low temperature or a bain-marie. The original container is microwave and oven safe up to 250 °C. Avoid overheating it: if it starts to smoke or bubble, the temperature is too high.
Is it possible to reuse scraps and off-cuts?
Yes, completely. Monster Clay Green Medium is reusable indefinitely. Scraps and off-cuts can be re-melted and mixed back into the main block without any loss of properties. This makes it a cost-efficient long-term investment compared to single-use materials.
Which other professional clays is it comparable to?
In the Feroca catalogue, Chavant Medium is another professional clay of equivalent hardness, also sulphur-free and reusable, with a different base. The choice between the two usually comes down to personal preference in terms of feel and heat response; many professionals try both and work with whichever best suits their technique.
What happens if Monster Clay contaminates a platinum silicone?
Being sulphur-free, Monster Clay Green Medium does not inhibit the cure of platinum silicones. However, other materials present in the studio can do so: sulphur-containing clays, latex, freshly cured epoxy, cyanoacrylate adhesives or unsealed surfaces. If the mould does not cure correctly, the cause is usually cross-contamination with one of these materials, not the Monster Clay itself.
How much material do I need to sculpt a full head?
For a life-size head with an internal structure (foam skull or armature), one 2.05 kg unit is usually sufficient for the modelling and detail layers. For a solid head without an armature, or to include the neck and part of the bust, two units are recommended. The ability to reuse leftover material means actual consumption is lower than with single-use materials.
