Abstract: A metal patching method and composition wherein the method comprises mixing two components and then heating to cure the mixture, one of the components containing a diazo dye which changes color when the mixture is cured. The composition of one component includes a bisphenol A epoxy resin, a diazo dye and a flow controlling agent of the temperature insensitive type, and the second component includes a polyamide resin and a flow controlling agent of the temperature insensitive type.