system an alkaline cyanide free copper plating bath can be used for this purpose based upon the use therein of the same complexing or chelating agent that is also used in the strike bath no zinc is needed in such plating baths for a heavy copper plating build up the copper concentration in the plating bath should be much higher than that used in the strike bath in order to permit higher plating speeds after the heavy build up of copper plating over the copper zinc alloy strike the substrate being coated is then generally further plated with nickel or bright nickel to a desired thickness followed by a top coat of chromium from a suitable chromium plating bath adhesion of the composite electrodeposit to the metal substrate part on which it is deposited in accordance with the present invention is generally tested by plating one half to 1 mil of copper plus one to one and a half mil of nickel onto the copper zinc alloy strike the rinsed and dried part is then placed onto a hot air oven maintained at about 125 u00b0 c for one hour after cooling to ambient temperature about 20 u00b0 25 u00b0 c the part is examined visually for the presence of blisters which would indicate poor adhesion of the plating to the substrate the part is also bent at right angles at ambient temperatures in a vise until broken any deposit lifting at the break would also indicate poor adhesion parts initially plated in the prior art alkaline copper only cyanide free strike baths have not been able to pass these adhesion tests whereas the copper zinc.