What’s the Difference Between Liquid and Putty Silicone Rubbers?

Understanding Liquid Silicone Rubber

Liquid silicone rubber is best when your project demands capturing intricate details or complex shapes. Its fluid nature allows it to flow easily over objects, reaching into nooks and undercuts that might be missed by thicker materials. For example, “Liquid Mould” silicone rubber is ideal for jewellery, prototypes or items with fine details. Liquid silicones generally require mixing with a catalyst and can take several hours to cure, but the result is a flexible, detailed mould that’s versatile for use with resin, wax, plaster or concrete.

When to Use Silicone Putty

Silicone putty is a more hands-on, malleable material that you can shape and press directly onto an object. This makes it perfect for making quick, small moulds of objects that do not have deep details or complex undercuts. Putty types, such as “I–Gum” silicone putty, are convenient because they cure far faster—usually in under an hour—and require no special equipment. This is particularly useful for decorators or hobbyists who need simple moulds for repeated use.

When This Matters Most

• If your object has very fine texture, holes, or complex geometry, liquid silicone rubber is the top choice.
• If you want speed or are making a basic form, silicone putty can get you a mould in under an hour with minimal mess.
• Liquid silicone is generally better for projects needing several high-quality reproductions, while putty is handy for quick, simple tasks or one-offs.