3M Scotch-Weld instant adhesive CA40 is a high strength, very fast-setting cyanoacrylate adhesive that cures at room temperature with very low bonding pressures. It has particularly good adhesion to many difficult to bond substrates such as EPDM rubber, aluminum and flexible vinyl. - 3M Scotch-Weld instant adhesive CA40 is a high strength cyanoacrylate instant adhesive. This low viscosity liquid adhesive bonds in only seconds (3 - 20 sec) while still allowing a brief amount of time for alignment of parts.