The modern electroplater; a complete book considering fully the elementary principles of electro deposition of metals, their practical application and industrial use . s in much less time than the pickling bath,and lessens the labor of scouring. Usually steel tanks are employed since they canthen be conveniently used for the anodes, being con-nected to the positive terminal of the generator cir-cuit. The electrolyte is an alkaline solution, such as 152 The Modern Electroplater caustic soda, kept near the boiling-point by meansof steam coils. The work to be cleaned is treated as acathode and is
The modern electroplater; a complete book considering fully the elementary principles of electro deposition of metals, their practical application and industrial use . s in much less time than the pickling bath,and lessens the labor of scouring. Usually steel tanks are employed since they canthen be conveniently used for the anodes, being con-nected to the positive terminal of the generator cir-cuit. The electrolyte is an alkaline solution, such as 152 The Modern Electroplater caustic soda, kept near the boiling-point by meansof steam coils. The work to be cleaned is treated as acathode and is, therefore, connected to the negativebns bar. An of 6 volts is sufficient, providing Negative Steel Tank -Piece BemgCleaned Fig. 99.—Electrolytic Cleaning. A Similar Process isEmployed in Copper Striking the current density is not less than 12 amperes persquare foot. As might be expected, an increase incurrent density quickens the cleaning action. Largequantities of hydrogen gas are thrown off from thesurface of the work, removing all traces of oxide andgrease. Only a few minutes are required for thisprocess, which is shown in diagram form in Fig. COPPER STRIKING Copper striking, or flashing, is another fa-vorite method of cleaning metal work. One advantageof this process is that a thin film of copper is depositedon the article, a perfect coating denoting a chemicallyclean surface. Upon this coating another metal maybe deposited with excellent results. As in the processdescribed in the paragraph on electrolytic cleaning, asteel tank, being positive, serves as the anode. The Hot Lye Dipping 153 article to be cleaned is connected to the negative ter-minal. An alkaline copper bath is used. Such anelectrolyte may be prepared to suit the the work from a mixture of water, copper cyanide,sodium cyanide, and caustic soda. A copper deposit,under such conditions, forms in a few moments. POLISHING Should the work now present a rough surface wherea fine smoot
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectelectro, bookyear1920
