J-B MarineWeld™ is a specially formulated two-part epoxy cold weld system that provides for strong, lasting repairs for bonding different or similar surfaces, such as aluminum, metal, composites, fiberglass and others. MarineWeld™ sets in 4 to 6 hrs at room temperature and is fully cured to a dark gray color in 15 to 24 hrs. Once cured, it can be shaped, tapped, filed, sanded and drilled and will retain its strength above or below the water surface.