Why Add Keys to Each Mould Half?

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When preparing a two-part silicone mould, adding registration keys to each mould half is vital to ensure a flawless casting process. Registration keys serve a crucial function in aligning mould sections and producing consistent, accurate results.

What Are Registration Keys and How Do They Work?

Registration keys are small, purposely designed features—such as dimples, notches, or protrusions—moulded into the joining faces of your silicone mould halves. When the halves are assembled, these keys and their corresponding recesses lock together, guaranteeing the mould fits in precisely the same way every time. This alignment prevents any shifting, gaps or misplacement that can cause visible seams or distortion in your castings.

Practical Benefits of Using Keys in Mould Making

The main advantage of including registration keys is leak prevention. Without proper alignment, resin or casting material can seep through misaligned mould seams, affecting the detail and integrity of your piece. Keys also help maintain the correct orientation for complex shapes, reducing the risk of mismatched details between the two halves. For instance, using a high-quality silicone like “Pure Mould” – Translucent Liquid Silicone Rubber for Mould Making makes it easy to add visible keys thanks to its transparency and flexibility.

When Registration Keys Matter Most

• Detailed or symmetrical designs: To ensure all features line up seamlessly after each pour.
• Repeated use: Essential for moulds that will be opened and closed multiple times, as keys maintain shape and avoid wear-related misalignments.
• Liquid casting materials: Especially important for resins and other low-viscosity media prone to leaking.

Related products

• "Pure Mould" – Translucent Liquid Silicone Rubber for Mould Making

Related guides

• How To Make Two Part Moulds For Modelling Resin

Adding registration keys is a straightforward but vital step in making reliable two-part moulds for modelling resin. For more essential mould making tips, visit our comprehensive guide on how to make two-part moulds for modelling resin.