Deposit rather than withdrawal

Plenty of machine tools exist to remove material, but somewhat fewer have the ability to put it back again.

Problem: Steve Benson, technical engineer of TDA Solutions, told Eureka that much of his company's present business arose from a problem encountered in the course of the building of the first concept Rediffusion 90 Flight Simulator. During construction, it was found that the bearing shells were oversized, however, the engineers did not want to take the machine apart and, instead, sought a solution. Solution: At the same time TDA happened to be doing some machining work for the same project and came up with the idea of hand plating the inside of the shells using equipment and chemical solutions developed by the US company Sifco. In this process an electrolyte solution is pumped through a porous anode, depositing metal on the surface to be plated which is connected to the negative side of the power supply and acts as the cathode. The plating solutions are designed to have unusually low throwing power, so plating only takes place near the anode and not elsewhere. TDA has since developed a small power driven lathe assembly, which can plate the inside (or outside) of circular components in an even manner. Applications: The most usual metal to deposit is copper, but the company is also able to deposit numerous others. The list includes: cadmium, chrome, cobalt, iron, lead, nickel, tin, zinc, Navy Babbit, nickel cobalt, tin indium, tin lead, cobalt tungsten, nickel tungsten, gold, indium, palladium, platinum, rhodium and silver. Because the process is low temperature, it causes none of the heat distortions liable to result from using plasma, arc or gas flame metal spraying. TS TDA Solutions