DESCRIPTION: THIS BOOK SHOWS YOU HOW TO SET UP YOUR OWN
SHOP. DISCUSSES VATS, HEATERS, RECTIFERS, EPA, BATH FORMULAS, BATH ANALYSIS, MORE. HAS A LIST OF SUPPLIERS.
ELECTROPLATING IS IN GREAT DEMAND, NOT ONLY IN RESTORING COLLECTOR CAR PARTS, BUT ALSO IN INDUSTRY. PRACTICALLY
EVERYTHING METAL IS PLATED. THIS INFORMATION IS RARELY
PUBLISHED AND CLASSES ON IT ARE EXTREMELY EXPENSIVE.
ELECTROPLATING OFFERS THE OPPORTUNITY TO BUILD AT YOUR
OWN PACE AND INCREASE YOUR INCOME SUBSTANTIALLY.
AUTHOR: RANDELL LYNN NYBORG
Anodes are the movable bars that hang suspended from the anode bus bar. They supply the positive current to the bath. They are strategically placed about the workpiece to provide it with sufficient current to plate. Anodes are usually constructed of a pure grade of the plating metal and are intended to corrode into solution at a rate equal to the metal that is removed from the solution and deposited onto the workpiece. If this occurs, the bath is said to be in balance. Chromium is an exception. Chromium anodes are not used; rather insoluble lead anodes are used. This requires that periodic addition of chromic acid be made to the bath to replenish it. Anodes also come in other shapes such as balls and "popcorn". These small anodes are placed in a metal basket and bagged. Controlling the amount of anode surface is easy as balls can be added or removed as needed.
In electroplating texts, frequent mention is made of cathode efficiency and anode efficiency. When metal salts as used in electroplating are dissolved into the bath, they ionize. An ion is an atom that has either gained or lost electrons in its outer shell. In this state, it will seek to restore its normal electron complement. The cathode supplies negative current to the bath and can be thought of as a source of electrons. The metal ions will be attracted to the cathode (workpiece) so as to restore their normal electron balance. Upon reaching the workpiece, they receive the balance of their lost electrons and their orbit interlocks with the orbits of the workpiece atoms' orbits and thus attach to the workpiece. An example is copper. If copper sulfate is dissolved into a bath, the copper disassociates from the sulfur and in the process, loses two electrons. It is attracted to the cathode (workpiece) in order to restore its normal electron state. Upon reaching the workpiece, it picks up two electrons and attaches to the workpiece. At the same time, an atom of copper from the copper anode which supplies the positive current to the bath, dissolves from the anode into the bath and leaves behind on the anode two electrons that travel up the anode to the power supply and complete the circuit. This atom of copper, actually an ion of copper, repeats the same process. The rate of deposition onto the cathode can be mathematically calculated. If the rate of deposition is less than it theoretically should be, the cathode is said to be less than 100% efficient. If the anode gives up atoms at a rate less than what it theoretically should, it is said to be less than 100 % efficient. You can see that if the anode is more efficient relative to the cathode, more metal ions will enter the solution than are taken from it. If the cathode efficiency exceeds that of the anode, more ions will be removed from the solution than are deposited into it.
If anode efficiency exceeds cathode efficiency, rough deposits may result. If cathode efficiency exceeds anode efficiency, inadequate plating may result.
TABLE OF CONTENTS:1. INTRODUCTION