From SLA to Silicone: Prototyping Methods Explained
Prototyping plays a critical role in product development by helping manufacturers test ideas, validate designs, and reduce costly errors before full production begins. However, not all prototypes are created equal. Choosing the right prototyping method depends on factors like material requirements, speed, cost, and the purpose of the prototype itself. Among the most commonly used techniques are SLA (stereolithography) and silicone molding, each offering unique advantages at different stages of development.
SLA prototyping is a popular rapid prototyping method ideal for early design validation. It uses ultraviolet (UV) lasers to cure liquid resin into solid 3D shapes, layer by layer. SLA prototypes are highly accurate and can capture fine details, making them excellent for visual models, fit testing, and even limited functional checks. Since the process is relatively fast, SLA is perfect when you need a prototype in a matter of days — often used in the earliest phase to confirm form, fit, and concept. While not suitable for high-stress applications, SLA models are cost-effective and excellent for presenting design intent.
On the other hand, silicone molding is typically used for short-run production or when the prototype needs to closely match the performance of the final part. In this method, a master model (often made via SLA) is used to create a soft silicone mold, into which polyurethane or other castable materials are poured. This results in parts that look, feel, and behave much like final injection-molded parts. Silicone molding is especially useful when testing functional parts that will be handled, assembled, or shown to end users. It also allows for multiple copies — typically between 5 to 100 units — making it ideal for bridge production or limited product testing before full-scale manufacturing begins.
Another benefit of silicone molds is the ability to test multiple material properties. By casting different resins, you can simulate rigid plastics, rubber-like textures, or even translucent materials — giving your team a chance to make more informed design decisions.
Choosing between SLA and silicone comes down to the stage of your product and what you’re hoping to learn from the prototype. SLA is fast, precise, and ideal for early iterations. Silicone molding takes more time but produces more durable, realistic parts that better reflect real-world usage.
Incorporating both methods strategically can speed up development, reduce tooling risks, and ultimately lead to a better final product. By working with an experienced prototyping partner, you can ensure that each step — from design to testing — is optimised for success.