This is a new bonding application for Casalini and the company presented Plexus with a tough list of requirements. High strength was necessary but with good flexibility. Excellent fatigue resistance and the ability to withstand stress were paramount.
Casalini also wanted to minimise processing times so it needed an adhesive with shorter working and fixture times as well as one capable of bonding substrates with little or no surface preparation.
Finally, the adhesive had to present no health and safety issues.
Plexus proposed a special methacrylate adhesive MA 422. Tests in the laboratory and in Casalini’s process confirmed that the adhesive met all requirements. The adhesive is now supplied to Casalini in cartridges and is machine-applied to the cabin wall. The frame is then positioned in place and held there while the adhesive sets.
“Originally we were using a two component PU [polyurethane] adhesive but after talking with Plexus and their local distributor Vaber we learned that MA 422 methacrylate adhesive would work much faster for us, increasing throughput and reducing our manufacturing costs," explains Casalini’s Production Manager Mr Fermi.
"Our material costs were also reduced by using an adhesive dispenser."