J-B Weld is The Original Cold Weld two-part epoxy system that provides strong, lasting repairs to metal and multiple surfaces. Mixed at a ratio of 1:1, it forms a permanent bond and can be shaped, tapped, filed, sanded and drilled after curing. At room temperature, J-B Weld sets in 4-6 hours to a dark grey color. A full cure is reached in 15-24 hours. J-B Weld has a tensile strength of 3960 PSI.