Custom Insert Molding: How Customized Solutions Drive High-Performance Part Production

Discover how Bost’s custom insert molding and customized solutions enhance high-performance part production. Our precision-engineered processes ensure durability and efficiency, driving innovation in manufacturing. Trust Bost for tailored molding excellence that meets your unique needs.

In daily life, household appliance terminal blocks with metal threads, automotive sensor plastic brackets with built-in copper pins, and medical connectors with metal contacts—these composite parts of "plastic + inserts" all rely on "custom insert molding" technology. Unlike standardized production, the core of custom insert molding is "customized": according to the needs of different industries, it customizes the choice of insert materials (metal, ceramic, etc.), plastic types (ABS, PP, PEEK, etc.), and matches customized molds and processes, ultimately achieving "1+1>2" part performance. To achieve this high level of customization, professional mold and process support is crucial, and BOST is a professional injection mold company that can provide full-process customized solutions.

The first step of custom insert molding is "customized material adaptation"—this is the foundation for determining whether the part can meet the needs of the scenario. The compatibility between the insert and plastic directly affects the bonding strength: for example, the household appliance industry needs to customize a heat-resistant "PP plastic + brass insert" combination (suitable for high-temperature kitchen environments); the automotive industry needs to customize an impact-resistant "PA66 + stainless steel insert" combination (to cope with driving vibrations); the medical industry needs to customize a "medical PC + titanium alloy insert" combination (to meet biocompatibility and disinfection resistance). Improper material matching can easily lead to loose inserts and plastic cracking. BOST is a professional injection mold company, and its technical team first conducts customized material tests to select the optimal combination for customers: for example, a medical enterprise needed to customize a connector with metal contacts, BOST recommended a "medical-grade PEI plastic + pure copper insert" combination, and improved the bonding strength through surface roughening (micro-patterns on the insert surface), ensuring that the part remained tight after 1000 disinfections.

"Customized mold design" is the core difficulty of custom insert molding and also the professional advantage of BOST. Unlike ordinary injection molds, custom insert molding molds need exclusive design for the number, position, and shape of inserts: if the insert has a multi-pin structure (such as electronic connectors), the mold needs to customize "multi-station positioning pins" to prevent insert displacement during injection; if the insert has a special-shaped structure (such as automotive special-shaped sensor inserts), the mold needs to customize "elastic clamping devices" to avoid insert deformation under pressure. BOST is a professional injection mold company, and for such customized needs, it uses 3D simulation technology to predict the mold operation effect: for example, when designing a mold for a "plastic interface with 4 copper pin inserts" for an electronic enterprise, BOST designed a "circular positioning groove + ejector pin limit structure" in the mold, ensuring that the copper pin spacing error was controlled within 0.02mm, fully adapting to the precision docking needs of electronic equipment.

"Customized process optimization" is the "final mile" of custom insert molding, directly determining the part qualification rate. Process parameters vary greatly for different customized combinations: for example, when injecting "thin-walled plastic + thin metal inserts", customized low pressure (to avoid insert bending) and slow speed (to ensure uniform plastic wrapping) are required; when injecting "high-temperature plastic (such as PEEK) + high-temperature resistant inserts", customized segmented temperature control (barrel temperature 340℃, mold temperature 120℃) is required to prevent plastic decomposition. BOST is a professional injection mold company with a customized process parameter database: for example, when customizing a "PEEK plastic + Inconel alloy insert" sensor bracket for an automotive enterprise, BOST customized the injection pressure to 90MPa (15% lower than ordinary processes), extended the holding time to 5 seconds, and matched it with a customized cooling water circuit (spiral around the insert), finally increasing the part qualification rate from the industry average of 82% to 99.3%.