Automated Liquid Shim Application

ABSTRACT: Our team will develop a method for applying exact controlled amounts of highly viscous Liquid Shim material within established Production process specifications for aircraft structure through an automated direct mixing/dispensing application tool. Currently, liquid shim is applied using pneumatic Semco guns which are loaded with cartridges of premixed Hysol EA 9377. Once mixed, these materials have a short application window before they become unusable. The aircraft is masked, and then the liquid shim is applied. After application of the liquid shim, the panels are placed on the structure and excessive"squeeze out"is removed post-cure. The process is labor intensive and prone to quality control issues that may hinder full-rate production. We will provide a solution that utilizes electronic control systems and sensors to monitor the various material/process parameters and deliver a precise amount of mixed base and catalyst at an optimum rate to specified areas in exact, but variable, amounts required by a production specification. BENEFIT: The current manual process is labor intensive and prone to quality control issues that may hinder full-rate production. Our team will identify and define a viable approach for on demand mixing/dispensing of liquid shim that can meet quality criteria relating to thickness, porosity, and application time.