J-B Weld PlasticWeld is a specially formulated two-part adhesive and epoxy filler system that provides for strong, lasting repairs. PlasticWeld will bond a variety of surfaces, such as metal, composites, fiberglass and others. PlasticWeld sets in 5 minutes at room temperature and is fully cured in 1 hour. Using a 1:1 mixing ratio, PlasticWeld combines to a tensile strength of 3900 PSI and cures to an off-white color.