What is Eyelet
An eyelet refers to a small metal component used for repairing damaged plated through-holes and vias in circuit boards. It serves the purpose of creating a conductive path and increasing circuit reliability. Eyelets are typically made from copper or brass with a bright tin plating, ensuring easy solderability and high conductivity.
These eyelets come in various sizes and configurations, such as flat flange or funnel flange, to accommodate different applications and requirements. The dimensions of the eyelets, including the inside diameter (ID), outside diameter (OD), length under flange (LUF), and flange diameter (FD), are crucial factors to consider when selecting the appropriate eyelet for a specific repair or application.
To properly install the eyelets, specific tooling is required. Manual setting tools, a tool base, and a tool grip can be used, or an eyelet press can be employed. The process of setting an eyelet involves applying firm and even pressure to flare the eyelet barrel using the flared end of the setting tool, followed by flattening the eyelet barrel with the flat end of the setting tool.
Eyelets are commonly available for purchase, with BEST Inc. being a supplier that offers them in large volumes and even provides eyelets of unique sizes upon request.
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