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CosClay - The Flexible Polymer Clay Revolutionizing Sculpting

CosClay represents a breakthrough in polymer clay technology. This hybrid plastic/rubber polymer clay maintains flexibility after curing, solving one of the biggest challenges sculptors face with traditional polymer clays - brittleness. Whether you’re creating posable figures, stop-motion characters, or delicate sculptures, CosClay’s unique properties open up possibilities that were previously impossible.

What Sets CosClay Apart?

Traditional polymer clays become rigid and brittle after baking, making them prone to breakage and unsuitable for posable pieces. CosClay changes this entirely by retaining flexibility after curing, creating a durable and resilient finished product.

Key Features

  • Post-cure flexibility - Pieces can be posed and repositioned without breaking
  • Durability - Resistant to breaking, chipping, and cracking
  • Non-toxic ingredients - Safe for studio use
  • Standard curing - Bakes at 135°C like other polymer clays
  • Versatile applications - From fine detail work to structural pieces

The CosClay Family

CosClay comes in several formulations, each designed for specific applications:

CosClay Sculpt - The original formula, perfect for character sculpting and detailed work. Offers the ideal balance of flexibility and firmness.

CosClay Doll - Specifically formulated for doll making, with a skin-tone color range and properties ideal for jointed dolls.

CosClay Deco - Designed for decorative applications and surface embellishment.

CosClay Elements - Special-effect formulations including translucent and metallic options.

Working with CosClay

Conditioning

Like all polymer clays, CosClay needs conditioning before use. Knead and warm the clay until it’s soft and pliable. A pasta machine dedicated to clay work makes this process much easier.

Sculpting Techniques

CosClay handles similarly to other polymer clays during the sculpting phase:

  • Detail work - Holds fine details exceptionally well
  • Blending - Colors can be mixed to create custom shades
  • Layering - Build up forms gradually for complex pieces
  • Armatures - Wire armatures work perfectly with CosClay
  • Tools - Responds well to all standard sculpting tools

Curing Requirements

Critical for success: Cure at 135°C for at least 30 minutes per 6.35mm of material thickness. Undercuring will compromise the final flexibility and durability.

Tips for Proper Curing:

  • Use an oven thermometer to verify temperature
  • Longer curing times are generally better than shorter
  • Tent pieces with aluminum foil to prevent browning
  • Allow pieces to cool completely before handling
  • Thicker areas may need extended curing time

Applications and Projects

Stop-Motion Animation

CosClay’s flexibility makes it ideal for stop-motion puppets. Characters can maintain poses without breaking, and replacement parts can be easily swapped.

Posable Figures

Create action figures and dolls with moving joints. The flexibility allows for repeated posing without wear or breakage.

Jewelry

Make durable jewelry pieces that won’t snap or crack with normal wear. The flexibility means earrings and pendants can handle impacts.

Cosplay and Props

Build lightweight, durable costume pieces that flex with movement rather than breaking.

Character Sculpting

Create detailed character sculptures with thin areas (like fingers and tails) that won’t break off.

Combining CosClay with Other Materials

Armatures

  • Wire armatures for posable figures
  • Aluminum foil bulks for larger pieces
  • Wood or metal structural supports

Mixed Media

  • Can be painted with acrylics after curing
  • Accepts most adhesives once cured
  • Can be sanded and carved
  • Compatible with varnishes and sealers

Advanced Techniques

Creating Joints

CosClay’s flexibility allows for several jointing methods:

  • Ball-and-socket joints using the clay itself
  • Wire-through construction for simple joints
  • Hybrid joints combining rigid and flexible elements

Thin Applications

Unlike traditional polymer clays, thin areas in CosClay won’t be brittle:

  • Delicate wings and fins
  • Thin fabric simulations
  • Fine hair strands
  • Translucent elements

Mold Making

CosClay can be used to create flexible molds for casting:

  • Press molds for textures
  • Small part duplication
  • Temporary molds for resin casting

Finishing CosClay Projects

Surface Preparation

  • Light sanding with fine-grit sandpaper for smooth finishes
  • Can be carved and detailed after curing
  • Wash with soap and water before painting

Painting

  • Acrylics work exceptionally well
  • Prime with gesso for best paint adhesion
  • Multiple thin coats better than single thick coats
  • Flexible paints and mediums recommended

Sealing

  • Water-based varnishes (matte, satin, or gloss)
  • Flexible sealers maintain the clay’s properties
  • Multiple thin coats for best results

Tips for Success

  1. Don’t underbake - Proper curing is essential for flexibility
  2. Test your oven - Oven temperatures can vary significantly
  3. Start small - Practice with small projects before tackling complex pieces
  4. Mix colors carefully - Colors lighten slightly when baked
  5. Store properly - Keep unused clay wrapped and away from heat
  6. Clean hands frequently - Prevents unwanted color mixing
  7. Use fresh clay - Old clay may not cure with optimal flexibility

Troubleshooting

Clay too soft: Leach between sheets of paper for 24 hours to remove excess oils.

Clay too firm: Add a few drops of mineral oil or clay softener and condition thoroughly.

Pieces cracking: Usually indicates undercuring. Ensure proper temperature and time.

Lost flexibility: Check curing temperature and time. Overbaking at too high temperature can affect properties.

Storage and Shelf Life

Store CosClay in a cool, dry place away from direct sunlight. Properly stored, it has a shelf life of several years. Keep colors separated to prevent unwanted mixing.

CosClay has fundamentally changed what’s possible with polymer clay. Its unique flexibility after curing makes it the go-to choice for any project requiring durability and movement. Whether you’re a stop-motion animator, doll maker, or sculptor, CosClay offers properties that traditional polymer clays simply cannot match.

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