Silicone Closed Moulds: Detail and Versatility Visualised

Closed moulds made from silicone unlock unmatched detail and consistency for resin casting. Their flexibility allows for easy demoulding of complex shapes, while translucent varieties help you spot potential issues before casting. Each type of silicone—liquid or putty—offers unique benefits for various model-making needs.

Step 1: Choose the Right Silicone Material

The selection of your silicone type is fundamental. Closed moulds for model-making resin demand a silicone that captures fine surface detail, accommodates possible undercuts, and resists degradation after repeated use. For highly detailed models, a flowable liquid silicone such as “Pure Mould” – Translucent Liquid Silicone Rubber for Mould Making is well suited thanks to its transparency and precision. For deeper undercuts or more complex forms, consider “Liquid Mould” – Casting Liquid Silicone Rubber, 5-40 Shores, Bi-Component A+B for its penetrating ability and variable hardness.

A non-toxic mould putty, such as “I–Gum” – Non-Toxic Silicone Putty for Mould Making, is a great choice for smaller or simple shapes that don’t require flow around deep details. Always check compatibility with your intended resin and ensure the working time matches your pace.

Step 3: Mix and Apply Silicone with Care

Carefully follow the manufacturer’s instructions for your chosen silicone. For flowable silicones, combine parts A and B in the correct ratios—typically 1:1 for Pure Mould, or as specified for Liquid Mould. Mix until fully homogeneous, scraping the sides of your container to avoid unmixed pockets. For putty formats like I–Gum, knead the two components together until the colour is uniform.

Pour or press the silicone slowly, starting from one corner, allowing it to flow around and beneath the master to reduce air bubbles. Tapping the container gently helps trapped air escape. For very fine models, the use of a pressure chamber can assist in eliminating bubbles prior to curing.

Step 5: Test and Prepare for Casting

Before performing full production runs, test your new closed mould with a small quantity of your chosen resin. For clear, detailed models, “Trasparente” – Multipurpose Clear Epoxy Resin for Casting – Up to 2cm delivers reliable clarity and minimal shrinkage in thin layers. Check for leaks or seam issues, inspect for bubbles in fine details, and ensure the mould releases cleanly from the resin part.

Once satisfied, repeat the casting process as needed, always observing for wear or tears in the closed mould. Store the mould flat, away from sunlight and heat, to extend its working life.

Get Creative: Closed Mould Applications in Model-Making

Silicone closed moulds are ideal for producing miniatures, custom parts, replicas, or intricate hobby components. Try alternating materials or colours in multi-part casts, or experiment with embedding elements within the resin. The right silicone and careful technique elevate your hobby or small-batch production capabilities.