J-B Weld (PRO Size) is the original cold weld two-part epoxy system. It provides strong, lasting repairs to metal and multiple surfaces. Mix this epoxy in 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 epoxy sets in 4-6 hours to a dark grey color. A full cure is reached in 15-24 hours. This automotive adhesive has a tensile strength of 3960 lbs. per square inch and sets to a hard bond overnight. J-B Weld epoxy can withstand temperatures up to 550 degrees Fahrenheit when fully cured.