Electroplating 
 
 A Treatise for the Beginner and for the 
 Most Experienced Electroplater 
 
 BY 
 
 HENRY C. REETZ 
 
 POPULAR MECHANICS HANDBOOKS 
 
 CHICAGO 
 
 POPULAR MECHANICS COMPANY 
 
 PUBLISHERS 
 
(LsON $ 
 
 b7o 
 
 ftji 
 
 Copyright, 1911 
 By 
 
 H. H. WINDSOR 
 
T HIS book is one of the series of 
 handbooks on industrial subjects 
 being published by the Popular 
 Mechanics Company. Like the 
 Magazine, these books are “written 
 so you can understand it,” and are 
 intended to furnish information on 
 mechanical subjects at a price within 
 the reach of all. 
 
 The texts and illustrations have 
 been prepared expressly for this 
 Handbook Series, by experts; are 
 up-to-date, and have been revised by 
 the editor of Popular Mechanics. 
 
CONTENTS 
 
 Page 
 
 Chapter I—Introduction . 9 
 
 Chapter II—The Electrical Equipment .15 
 
 Chapter III—Shop Equipment.30 
 
 Chapter IV—Cleaning Goods before Plating.53 
 
 Chapter V—Copperplating.56 
 
 Chapter VI—Nickelplating .58 
 
 Chapter VII—Silverplating .65 
 
 Chapter VIII—Goldplating .74 
 
 Chapter IX—Miscellaneous .85 
 
 Chapter X—First Aid to the Injured .92 
 
 Chapter XI—Business Suggestions.96 
 
ELECTROPLATING 
 
 CHAPTER I 
 
 INTRODUCTION 
 
 E LECTROPLATING, as commonly understood, is the 
 coating of an inferior with a more valuable metal by 
 means of electricity. It is scientifically defined as “the 
 art or process of covering any electrically conducting mate¬ 
 rial with an adherent and lasting film of metal, in a bath 
 containing a solution of that metal, by means of the elec¬ 
 trolytic action induced by a current from a battery or 
 dynamo.” This technical definition may seem rather diffi¬ 
 cult for the average reader to understand, but will be made 
 plain as we proceed step by step with the subject. 
 
 It is not necessary that the electroplater, in making a 
 beginning, should have a scientific knowledge of chemistry 
 and electricity, although, unquestionably, the better posted 
 he is in those branches of the sciences that relate to his 
 trade, the more likely he is to succeed. While it is quite 
 possible for a man of average skill to fit himself to be an 
 expert electroplater in certain lines, by a careful study of 
 methods and apparatus, and especially by imitating a 
 practical plater, yet it goes without saying that, the more 
 he can absorb of the real science of the business, the why 
 of the how, the less will be his trouble with batteries and 
 solutions and the greater will be his success. 
 
 In this handbook, therefore, we will endeavor to give 
 brief and practical directions calculated to be of benefit to 
 those already engaged, as well as to those about to engage, 
 in the electroplating business, with no more technical detail 
 than is necessary for practical work, and yet with such 
 explicit directions concerning the actual operations as an 
 
 9 
 
10 
 
 INTRODUCTION 
 
 old hand at the business thinks may be useful to the 
 beginner. 
 
 Two things will be urged at the start, and, but for the 
 necessity of being brief, they would be repeated on every 
 page, for without them success cannot be expected. They 
 are: 
 
 Use care at every step. Nowhere is carelessness more 
 costly than in the electroplating shop. Constant vigilance 
 is the price of success. 
 
 Study the why of things. Know why you do this and 
 that, and you will be more apt to do it right. If you know 
 what you are about at every stage of the process and do 
 things right, the work will come out right, and all will be 
 well. If you blunder along, hit or miss, you will be inquir¬ 
 ing the price of junk before you are six months older. 
 
 OLD AND NEW METHODS 
 
 In electroplating, the apparatus which supplies the elec¬ 
 tric current, through the aid of which the film of metal is 
 deposited on the article to be plated, is, of course, the essen¬ 
 tial feature. The ancients used to hammer out a thin leaf 
 of gold or silver and solder it to a surface, often doing 
 really excellent work, but this was a most tedious and 
 expensive process. A kind of plating is also done by 
 immersion in melted metal, usually a soft composition. 
 This is not permanent and could not be employed with 
 precious metals on account of the expense. 
 
 Modern plating, or real plating, is electroplating, by 
 which we use a small amount of metal, deposit it evenly, 
 thoroughly, and in a short time, and yet obtain lasting and 
 most satisfactory results. Electric current does the work. 
 
 HOW METAL IS DEPOSITED 
 
 In simple forms of electroplating apparatus, the bath 
 containing the metallic solution may itself form the bat¬ 
 tery, and copper is easily deposited in this manner. The 
 
INTRODUCTION 
 
 11 
 
 more common and practical plan, however, is to obtain 
 current from a source outside the bath, as from a regu¬ 
 larly constructed electric battery or dynamo. 
 
 When articles are to be electroplated, they are suspended 
 by wires in the plating tank, which contains a solution of 
 the metal which is to be deposited on them. From another 
 
 wire is hung a piece of the same metal as that in the 
 solution. The articles to be plated are connected by a 
 wire to the negative pole of a battery and the metal plate 
 is connected in the same way to the positive pole of the 
 battery. 
 
 Now the metallic solution in the tank will conduct the 
 electricity, and so a complete electric circuit is formed 
 
12 
 
 INTRODUCTION 
 
 by which the current flows from the positive pole of the 
 battery through the connecting wire to the metal plate 
 hanging in the tank. From the metal plate, it flows through 
 the solution to the article to be plated and thence back 
 through the other wire to the negative pole of the battery 
 —completing the circuit. Fig. i shows the path of the 
 current in an electroplating circuit. 
 
 The metal plate attached to the positive pole of the bat¬ 
 tery is called the “anode” and the objects to be plated in 
 the tank are called “cathodes.” The use of these terms 
 can be understood if we think of the battery as being below 
 
 the plating tank, as shown in the illustration. “Anode” is 
 a Greek word meaning “the way up”—from the battery 
 to the solution—and “cathode” means “the way down.” 
 By the action of the current, particles of metal are attracted 
 from the solution to the articles to be plated, and at the 
 same time an equal amount of the same metal is thrown 
 off the anodes into the solution. Thus, although the solu¬ 
 tion is being constantly robbed of metal* it is being fed at 
 the same time, and so its strength is maintained. Of 
 course, the anodes must be plates of the same metal as 
 that contained in the solution; thus, silver anodes in a sil- 
 
INTRODUCTION 
 
 13 
 
 ver solution, nickel anodes in a nickel solution, etc. The 
 process by which the electric current affects the decompo¬ 
 sition of the metal to be deposited on the articles to be 
 plated is called “electrolysis.” 
 
 To make all this very plain, and to start the beginner at 
 once with a practical working experiment, the diagram, Fig. 
 2, shows a very simple plating outfit which anyone can make 
 at home. The explanations given will help the beginner 
 to master the first principles of electroplating. A silver- 
 plating outfit has been selected for illustration because sil¬ 
 ver is the metal most easily deposited and therefore is'a 
 favorite with experimenters. 
 
 HOW TO MAKE A SMALL SILVERPLATING OUTFIT. 
 
 For a tank take an ordinary glass fruit jar or any other 
 receptacle of glass, not metal, which will hold i qt. of 
 liquid. Fill it nearly full with rain or distilled water and 
 then add ^4 oz. of silver chloride and ij/2 oz. of chemically 
 pure potassium cyanide. Let this dissolve and incorporate 
 well with the water before using. This is the bath. 
 
 Take an ordinary wet battery and fasten two copper 
 wires to the terminals, as in Fig. i. Fasten the other ends 
 of the wires to two rods of heavy copper wire or in. 
 brass pipe, which are to be laid across the top of the 
 “tank.” The wires must be well soldered to the -rods to 
 make a good connection. 
 
 When the solution is ready, which is when the crystals 
 are entirely dissolved, the outfit is ready for work. Pro¬ 
 cure a small piece of silver, a silver button, ring, chain, or 
 anything made entirely of sterling silver, fasten a small cop¬ 
 per wire to this, and hang it by this wire to the rod con¬ 
 nected with the carbon of the battery. This forms the 
 anode. The article to be plated is to be suspended in a 
 similar manner from the other rod and will form the 
 cathode. 
 
 Be sure that the article to be plated is chemically clean. 
 
14 
 
 INTRODUCTION 
 
 It may be cleaned by scrubbing with pumice and a brush sat¬ 
 urated in water. When cleaning an article, there should 
 always be a copper wire attached to it. It should never be 
 touched by the hand after you have once started to clean 
 it, because the touch of the fingers will deposit enough 
 grease to cause the silver plate to peel off when finished. 
 When well scoured, run clear, cold water over the article 
 and, if it appears at all greasy, place it in hot water. When 
 well cleaned, place it in the plating bath and carefully 
 watch the results. 
 
 If small bubbles appear on the surface of the bath, you 
 will know that you have too much of the anode immersed 
 and you must draw out the piece until you can see no more 
 bubbles. The surface of the anode should be about the 
 same as the surface of the article to be plated. If the 
 anode is too large, bubbles will appear, as stated; if too 
 small, the metal contained in the solution will be exhausted. 
 
 Leave the piece to be plated in the solution for about 
 half an hour, then take it out, clean ofif the yellowish scum 
 with a toothbrush and some pumice, rinse in clean water 
 and dry in sawdust. When it is thoroughly dry, take a 
 cotton flannel rag and some polishing powder and polish 
 the article. It must have a fine polish before plating if it 
 is desired to have a finely polished surface after the plate 
 is put on. 
 
 To see if your battery is working, take a small copper 
 wire and touch one end to the anode rod and the other to 
 the cathode rod. When these two ends are touched and 
 separated, there should be a small spark. 
 
 This description applies only to silverplating. Articles 
 of lead, pewter, tin or any other soft metal cannot be 
 silverplated unless they have first been copperplated. This, 
 as stated, is merely an experiment to interest the beginner 
 and to form a sort of object lesson which will enable him 
 to grasp more easily the details which follow and the 
 reasons why. 
 
CHAPTER II 
 
 THE ELECTRICAL EQUIPMENT 
 
 E LECTRIC current used for electroplating is derived 
 either from voltaic cells or from dynamo-electric gen¬ 
 erators, usually called “dynamos.” If power is available, 
 a dynamo is of course in the long run the most economical 
 means of producing the electric current required for electro¬ 
 plating. But if a dynamo is out of the question, either for 
 want of power or on account of the initial expense, its 
 place can be very satisfactorily filled by batteries coupled 
 together in sufficient number to produce the required cur¬ 
 rent. 
 
 ELECTRIC BATTERIES 
 
 An electric battery is composed of several cells, although 
 a cell is sometimes called a battery. The cells are of vari¬ 
 ous kinds, wet and dry, and the wet cells may be of single 
 or double liquid. The types described below refer to kinds 
 or patterns of cells, and not to any special patents. There 
 are as many special kinds of electric cells, or batteries, as 
 there are manufacturing concerns, and even more. • As a 
 general rule, the higher-priced cells are likely to be worth 
 all the money asked, and the cheaper ones really cost more 
 in the end. This rule will apply pretty generally to chem¬ 
 icals and to all supplies. The beginner is advised to get as 
 few articles as possible, and get the best; then to use them 
 carefully, so as to get the greatest value out of them. 
 
 With regard to the different kinds of cells, the Smee and 
 Wollaston are perhaps the most common types of single- 
 liquid cells, and the Daniell, Fuller, Bunsen, and gravity 
 cells may be taken as representative patterns of double¬ 
 liquid cells. The principle consists in the exciting of an 
 electric current by the solution (by an acid or an acid salt) 
 of the readily attacked (or “negative”) metal, in conjunc- 
 
 15 
 
16 
 
 THE ELECTRICAL EQUIPMENT 
 
 tion with a metal or other element (as carbon) not so 
 readily attacked (this being called the “positive” metal or 
 element), the effect being to produce what is called a “dif¬ 
 ference of potential” which sets up an “electromotive 
 force” that tends to drive a current of electricity around 
 the circuit when a passage is completed for it outside the 
 cell. 
 
 The electric current has several properties, among which 
 we may consider force and quantity, both of which are 
 governed or influenced by the resistance of the bodies 
 through which the current passes. This has often been 
 compared to water in a pipe, which may be under a varying 
 
 pressure according to the level, 
 and may have a flow according 
 to the opening at the faucet. The 
 difference of potential may be 
 likened to the water level, the 
 electromotive force to the pres¬ 
 sure, and the current to the flow 
 or volume of water. For some 
 purposes, a very high voltage* is 
 required, and for others, as in 
 electroplating, a low voltage and 
 a large volume of current are 
 needed. We will now consider 
 the construction of the cells, and 
 then the methods of connecting 
 them to get the desired results. 
 THE SMEE CELL 
 
 The Smee cell, Fig. 3, is a 
 square glass jar having two zinc 
 plates held together by a clamp, 
 and between them, well insu¬ 
 lated, a platinum plate, or a sil¬ 
 ver plate covered with “plat- 
 
 *The " volt ” is the practical unit of electromotive force. The “ohm" is the 
 unit of resistance. The “ampere” is the unit of current. 
 
 Fig'3. Smee Cell 
 
THE ELECTRICAL EQUIPMENT 
 
 17 
 
 inum black,” which is a preparation of finely divided 
 platinum, black in color, obtained by the action of potassium 
 hydrate on platinum chloride. 
 
 Platinum black has the property 
 of absorbing’ or occluding gases, 
 and is employed in the Smee cell 
 for this purpose. The plates 
 must have sufficient room so as 
 not to come in contact with the 
 zinc sulphate that forms by the 
 dissolving of the plates. The 
 vessel is filled with a solution of 
 sulphuric acid (by measure, i 
 part of the acid to 7 parts of 
 water) and is then ready for 
 use. Connections are made by a 
 small copper wire, No. 16 gauge, 
 with the zinc element to the Fig. 4. DanieiiCeii 
 cathode rod, and from the plat¬ 
 inum element to the anode rod. Several cells may be placed 
 together in a frame and connected to form a battery. The 
 Smee cell has the advantage of being able to give a fairly 
 steady current for a long time, as the platinum black prevents 
 the accumulation on the positive element of bubbles of gas 
 which would result in a decrease, and final stoppage of the 
 current, an effect known as “polarization.” 
 
 THE DANIELL CELL 
 
 The Daniell cell, Fig. 4, is composed of a glass or stone 
 jar containing a cylindrical plate of sheet copper and an 
 inner porous pot or jar of unglazed earthenware contain¬ 
 ing a zinc rod. The porous pot is filled with dilute sulphuric 
 acid, while in the outer part the copper plate is immersed 
 in a saturated solution of copper sulphate. The electro¬ 
 motive force of the Daniell cell is about 1 volt. The inter¬ 
 nal resistance is about 3 ohms. 
 
18 
 
 THE ELECTRICAL EQUIPMENT 
 
 The Daniell cell is recharged thus: Thoroughly clean 
 all the parts and re-amalgamate the zincs. Re-amalgama¬ 
 tion is for the purpose of freeing the surface from impur¬ 
 ities and is thus accomplished: Take a flat earthenware 
 dish a little larger than the zinc plate, and put in just 
 enough water to cover it. Then slowly add sulphuric acid, 
 one part to the ten of water—that is, if you have io oz. of 
 water, add i oz. of sulphuric acid. Immerse the zinc in 
 the diluted acid and pour over it a small quantity of mer¬ 
 cury which is to be painted onto the zinc with a little brush 
 or mop made up of tow and a few brass wires. See that 
 the zinc is well covered. The acid may be afterward used 
 with the charging solution, and the mercury that is left 
 may be poured back into the bottle. 
 
 After the zincs are thus re-amalgamated, charge the 
 porous pot with a solution of i part of sulphuric acid to 12 
 of water, and the outer jar with a saturated solution of 
 copper sulphate. On a sieve suspended in the liquid, place 
 crystals of copper sulphate, to keep the solution saturated. 
 Do not throw a handful of the sulphate into the jar to 
 settle at the bottom. Care should be taken to keep the 
 zinc and the zinc sediments from touching the porous pot, 
 as this would attract particles of copper from the copper 
 solution to form on the outer wall of the partition and 
 cause a higher internal resistance and short circuit. 
 
 If properly understood and kept in working order, the 
 Daniell battery is very constant, and is well suited to 
 silverplating. 
 
 THE BUNSEN CELL 
 
 The Bunsen cell, Fig. 5, has several forms, of which the 
 English and the French are the best known. The English 
 Bunsen is similar in appearance to the Daniell, with a 
 cylinder of amalgamated zinc in place of copper, and a 
 square of carbon in place of the zinc rod. The outer cell 
 is charged with dilute sulphuric acid, 1 part of acid to 10 
 
THE ELECTRICAL EQUIPMENT 
 
 19 
 
 parts of water, and the inner cell with strong commercial 
 nitric acid. Run the nitric acid into the porous cell until 
 about three-quarters full, and fill the 
 space between the porous cell and the 
 outer jar with the dilute sulphuric acid. 
 The French Bunsen has sulphuric acid 
 in the porous cell with the carbon, pro¬ 
 ducing a constant generator with a low 
 voltage, or electromotive force. This 
 cell gives 1.8 volts at starting, falling to 
 1.5 volts when the circuit is closed. This 
 form is less troublesome to keep in work¬ 
 ing order than the English Bunsen and 
 is free from noxious fumes. 
 
 An English authority says: “The type 
 of cell known as the Daniell is best for 
 depositing copper from its sulphate solu¬ 
 tion and silver from the usual plating 
 solution, but the Bunsen may be used for 
 this purpose if the exciting liquid is 
 sufficiently weakened. One or two large cells in series 
 will be enough for all ordinary purposes” (presumably, 
 for small work, such as the country repair shop). 
 
 The Bunsen cell is best for depositing copper and brass 
 from their alkaline solutions, and also fqr the deposition 
 of nickel, because its electromotive force is high, enabling 
 it to pass through high resistances. It is not suitable for 
 the work of silverplating, gilding, and electrotyping be¬ 
 cause its e.m.f. (electromotive force) causes the metal to 
 go on too fast, and in a granular condition. In all these 
 operations the Daniell cell will be found to be the best, 
 because its e.m.f. is lower than that of the Bunsen, and its 
 current equally constant in volume. The Smee cell is emi¬ 
 nently useful for gilding small pieces of jewelry. Batteries 
 with a high e.m.f. cause gold to go on too fast, and to give 
 the deposits a brown color. So much has been said, though 
 
20 
 
 THE ELECTRICAL EQUIPMENT 
 
 very briefly, descriptive of the leading types of batteries in 
 use. The beginner will find it to his advantage to study the 
 battery which he has adopted, and to become thoroughly 
 familiar with its operation. 
 
 HOW A BATTERY WORKS 
 
 The cells forming the battery are connected up in various 
 ways to obtain different results. We wall explain, as 
 briefly and simply as possible, the working of the cells in the 
 battery, and how the electric current is controlled, since it 
 is important in plating operations to get the proper pres¬ 
 sure and current, depending upon a known resistance. 
 Scientific terms will be avoided, except when necessary to 
 make the statement exact. 
 
 In considering the flow of current in an electric circuit, 
 we can compare it nicely with the flow of water in a water 
 pipe. Suppose we had a pail of water with a pipe in the 
 bottom. We know that the higher the water stands in the 
 pail, the more rapidly the water will flow through the pipe, 
 and that it makes no difference how big the pail, providing 
 the water level is the same. Now we can think of a bat¬ 
 tery cell as a pail of water and an electric current as the 
 flow through a pipe leading from the pail. To correspond 
 to the pressure of the water on the bottom of the pail, we 
 have the electromotive force which, in fact, is usually 
 called the “pressure” or “voltage,” and which we will call 
 hereafter the e.m.f. The rate of flow of the electric cur¬ 
 rent corresponds to the rate of flow of water, and it 
 depends upon the pressure (e.m.f.) of the battery, just as 
 the rate of the water in the pipe depends upon the pressure 
 of the water in the same way. No matter how big the 
 battery; the current will be no greater in the circuit if the 
 pressure remains the same. We also know that in a water 
 pipe, other things being the same, the larger the pipe, the 
 more rapidly will the water flow (in gal. per min.). In 
 the electric circuit, the larger the wire, the greater the 
 
THE ELECTRICAL EQUIPMENT 
 
 21 
 
 current will be, for the larger wire offers less resistance to 
 the flow of electricity. Some substances offer more resist¬ 
 ance to the flow of electricity than do others; that is why 
 copper wire is used so much, as copper offers less resist¬ 
 ance to the current than most other substances. Now if 
 we put a valve in our water pipe, we can change the flow 
 of the water (the current) by opening or closing the valve, 
 that is, we put more resistance in the path of the water. 
 In the same way, we can put a valve in the electric circuit, 
 by which we can vary the current from the battery by in¬ 
 troducing more or less resistance. Such a valve is called 
 a “resistance box” or “rheostat.” 
 
 The pressure of water is measured in lb. per sq. in.; 
 electric pressure is measured in volts. The rate of flow 
 of water is measured in gal. per min.; the rate of flow of 
 electric current is measured in amperes; and the resistance 
 offered to this flow is measured in ohms. There are two 
 resistances to be considered, that of the cell or battery 
 itself, called “internal resistance,” and that of the circuit 
 (the wires, solution, etc.) called “external resistance.” 
 
 There are many ways of grouping the cells in a battery, 
 but they are comprehended in the systems known as 
 “series” and “parallel” and combinations of the two, called 
 “series-parallel.” 
 
 In series, the cells are connected with the positive ele¬ 
 ment of one joined to the negative of the next and so on, 
 and the free elements connected to the main circuit, as 
 shown at A, Fig. 6. In this arrangement, the current gen¬ 
 erated in the first cell has to flow through the second, and 
 the e.m.f. of one is added to that of the other. This method 
 corresponds to setting one pail of water on another, in 
 which case we double the pressure. 
 
 The parallel grouping of the cells has a different effect. 
 In this, all the negative elements are joined together on 
 one wire, and all the positive elements to the other wire, 
 as shown at B. This is called “joining for quantity.” The 
 
22 
 
 THE ELECTRICAL EQUIPMENT 
 
 zincs are practically all one large zinc, and the coppers (or 
 carbons) are one big positive element. The force is no 
 greater, but the internal resistance is decreased in propor- 
 
 A 
 
 Fig. 6 Grouping of Cells—A, Series—B, Parallel—C, Series-Parallel 
 
 tion to the number of cells, as there are more paths through 
 which the current may flow. The current is therefore in¬ 
 creased in proportion to the number of cells thus con¬ 
 nected. The e.m.f. is no more altered than would be the 
 
THE ELECTRICAL EQUIPMENT 23 
 
 total water pressure, produced by placing two pails of 
 water side by side on a level floor, in place of one; for both 
 cells are giving the same pressure, and coupling them in 
 parallel is only equivalent to increasing the size of a single 
 cell, which has no influence on the e.m.f. 
 
 The series-parallel grouping, shown at C, unites two or 
 more sets of cells which were joined in series in a parallel 
 arrangement. 
 
 The practical results of these combinations may be fig¬ 
 ured out from a knowledge of the capacity of the cells and 
 the resistance, by a formula known to electricians as Ohm s 
 law, which declares that the current is equal to the e.m.f. 
 divided by the resistance. This law can be expressed by a 
 
 E 
 
 formula, which for any cell is I = —- where I equals 
 
 r -f- R 
 
 the current in amperes, E = the e.m.f. in volts, R = the 
 external resistances of the circuit in ohms, and r the in¬ 
 ternal resistance of the cell in ohms. 
 
 Suppose we have four cells of a voltage of 1.5, an ex¬ 
 ternal resistance in tanks, wires, etc., of 2 ohms, an internal 
 resistance of .05 ohm, and wish to know the current given 
 by the three combinations. Here E = 1.5, r — -° 5 > R = 2 - 
 The various methods of grouping are as follows: 
 
 A.- SERIES GROUPING. 
 
 Electromotive force of one cell = i* 5 > 4 ce ^ s 
 
 in series = 4 X 1-5 = 6 volts. 
 
 Internal resistance of one cell = 0.05 ohm; internal re¬ 
 sistance of 4 cells = 4 X 0.05 = 0.2 ohm. External re¬ 
 sistance = 2 ohms. Total resistance = internal resistance 
 of 4 cells -(- external resistance = 0.2 -f- 2 = 2.2 ohms. 
 
 electromotive force 
 
 Current (I) = 
 
 total resistance 
 
24 
 
 THE ELECTRICAL EQUIPMENT 
 
 6 
 
 Current —-= 2.73 amperes, nearly. 
 
 2.2 
 
 B. —PARALLEL GROUPING. 
 
 Electromotive force of cells in parallel is the same as 
 that of a single cell, if the cells are identical. That is, the 
 e.m.f. = 1.5 volts. 
 
 The internal resistance of 4 cells in parallel is % of that 
 of one cell. That is, the internal resistance is 0.05 -h- 4 — 
 0.0125 ohm. The external resistance is 2 ohms. There¬ 
 fore, the total resistance = 0.0125 2 — 2.0125 ohms. 
 
 electromotive force 
 
 Current (I)=- --. 
 
 total resistance 
 i -5 
 
 =- ■— 0.74 ampere 
 
 2.0125 
 
 C. —SERIES-PARALLEL GROUPING. 
 
 Electromotive force is double that of one cell; that is, 
 the e.m.f. = 1.5 X 2 = 3 volts. 
 
 The internal resistance of each set of two cells in paral¬ 
 lel is one-half that of each cell, = 0.05 -u 2 — 0.025 ohm 
 The total internal resistance of the two groups in series is 
 twice that of either group singly, that is, 0.025 X 2 = 0.05 
 ohm. External resistance = 2 ohms. Therefore, total 
 resistance = 0.05 -)- 2 — 2.05 ohms. 
 
 electromotive force 
 
 Current (I) = --- 
 
 total resistance 
 
 3 
 
 — --= 1.46 amperes 
 
 2.05 
 
 Suppose, however, that the external resistance is not so 
 great as assumed in the above examples, in which it is pur¬ 
 posely made rather high. On a “short circuit” (very little 
 
THE ELECTRICAL EQUIPMENT 
 
 25 
 
 external resistance), R = o and we find the current from 
 these three combinations as follows: 
 
 1 - 5 X 4 6 
 
 (A) I =-—:-— 30 amperes. 
 
 .05 X 4 -2 
 
 i -5 i -5 
 
 (B) I —-=-- = 120 amperes. 
 
 .05 A-4 -0125 
 
 1-5X2 3 
 
 (C) 1 =-=-= 60 amperes. 
 
 •05 -05 
 
 So that, while with a heavy external resistance we get 
 the greatest volume of current from the series coupling, 
 with a low resistance we get the greatest volume of current 
 from the parallel, which at the same time gives the weakest 
 voltage. From the above it is evident that the voltmeters 
 and rheostats which will be treated later, must be sharply 
 watched if the plater would know what he is doing. 
 
 THE DYNAMO 
 
 After learning the rudiments of the trade with such 
 small electric batteries as are found most practical, the 
 electroplater may feel warranted in using a dynamo. If 
 one has some electrical training and mechanical ability he 
 may be able to build a very serviceable dynamo for him¬ 
 self. This, however, is a separate trade, and the electro¬ 
 plater is apt to have his hands full in his own particular 
 line. As a rule, it will pay him better to buy a good dynamo 
 and use all his time in his regular business. The advan¬ 
 tages of a dynamo in a shop where a good custom trade is 
 established are that it yields a current in every respect 
 more suitable to the work of depositing metals than from 
 the best batteries, it is more cleanly in working, eliminates 
 noxious gases, and is more easily managed. 
 
 The best form of dynamo for the use of the electro- 
 
THE ELECTRICAL EQUIPMENT 
 
 2G 
 
 plater is some sort of shunt-wound or compound-wound 
 machine, giving a large volume of current at low pressure, 
 the current being delivered constantly and in one direction. 
 In the shunt-wound dynamo, there is automatically a con¬ 
 tinuous balancing of the current as the load varies in the 
 external circuit. The compound-wound machine, however, 
 can also be designed to give a constant current, and has, in 
 addition, self-regulating features not possessed by the 
 shunt-wound machine. It is the best type of machine to 
 use for electroplating. Such a generator is shown in Fig. 
 7. Machines for electric lighting work are designed to 
 give a moderate volume of current at high pressure, and 
 while a plating dynamo will generate current at, say, 10 
 volts, the lighting current may have a pressure of no or 
 220 volts, or higher. The unfitness of the lighting current 
 for the purposes of the electroplater is therefore manifest. 
 
 Fig. 7. Compound-Wound Dynamo 
 
THE ELECTRICAL EQUIPMENT 
 
 27 
 
 In purchasing a dynamo, avoid all offers of second-hand 
 machines, although warranted “as good as new,” Get a 
 small machine of a responsible dealer, at a cost of $50 or 
 upwards, and then master its construction and working so 
 as to get the best results. It may be set down as a law in 
 electrical engineering, though probably never before 
 printed, that a dynamo will deteriorate and go to scrap 
 with a velocity equal to the square of the ignorance of the 
 operator. 
 
 REGULATING AND MEASURING INSTRUMENTS 
 
 A rheostat, to enable the plater to control the current, 
 is necessary where a dynamo or large battery is used. One 
 style of rheostat is shown in Fig. 8. -Throwing aside tech¬ 
 nical terms, the rheostat is similar to a tap or valve in a 
 
 Fig 8. Rheostat 
 
28 
 
 THE ELECTRICAL EQUIPMENT 
 
 water pipe, each wire taken in by it acting like the plug 
 of a tap narrowing the orifice through which the liquid 
 flows. 
 
 The ammeter, Fig. 9, measures the rate of flow of cur¬ 
 rent, in amperes, and is sometimes made in connection 
 with the voltmeter. As 1 ampere of current, under proper 
 conditions, will deposit in 1 hour 62.1 gr. of silver, 18.3 gr. 
 of copper (from cuprous solutions), or 36.6 gr. of gold 
 (from aurous solutions), it is evident that the plater should 
 regulate his current according to the work in hand. 
 
 The voltmeter is similar to the ammeter, but measures 
 the pressure of the current in volts. In Fig. 10 is shown 
 
THE ELECTRICAL EQUIPMENT 
 
 29 
 
 a voltmeter with a switch for connecting it to any given 
 number of tanks. Experience shows that the silver in a 
 plating solution may be separated from its salt and depos¬ 
 ited in good condition with a current at as low a pressure 
 as 2 volts, which may be increased, if required to work 
 more rapidly, to even 3 snd 4 volts. When the piessure 
 exceeds the latter figure, however, there is a tendency to a 
 loose and powdery deposit. So it becomes necessary to 
 regulate the pressure, or voltage, as well as the current or 
 number of amperes. It is not necessary to explain here the 
 construction of these meters, or even their arrangement, 
 the latter depending on the number and size of the tanks 
 and batteries used, and full directions may be obtained of 
 the supply house from which the equipment is purchased. 
 
CHAPTER III 
 
 SHOP EQUIPMENT 
 
 \X^E WILL NOW consider the tanks, scrubbing trough, 
 polishing lathes, brushes and other furniture! 
 Trough and tanks may be made by the beginner himself, if 
 he is a good mechanic. But if he is not handy with tools,’or 
 
 if his time can be profitably employed otherwise, he would 
 better buy them ready made, or have a carpenter make 
 them for him. 
 
 T° make a small tank (inside dimensions 6 by 18 in. 
 with an inside depth of 12 in.) you will require— 
 
 30 
 
SHOP EQUIPMENT 
 
 2 pieces for sides 12 by 21 in. 
 
 2 pieces for ends 8 by 12 in. 
 
 1 piece for bottom 9 by 21 in. 
 
 The wood should be ij/2 in. thick and of good soft wood 
 without knots. The pieces must be cut true and square, 
 or it will be impossible to make the tank water-tight. Rab¬ 
 bet the ends of every piece except the 9 by 21, which is the 
 bottom. Fig. 11 shows the rabbeting of the boards and 
 Fig. 12 shows how they are put together. Use large wood 
 screws, not nails, in joining the parts. Before joining, 
 brush white lead thickly where the grooved ends come to¬ 
 gether, and put in the screws while the white lead is still 
 wet. Then take some cotton waste or like material and 
 calk all the crevices. Calk from the outside of the tank. 
 
 The next process is to line the tank with asphaltum. For 
 a tank of this size, allowing 1 lb. for each gal. of capacity, 
 6 lb. of asphaltum will be required, the capacity of this 
 tank being just 5.6 gal. This will be a liberal allowance and 
 make a good tank lining. The asphaltum should be secured 
 from some good platers’ supply house, because if mixed by 
 an inexperienced person it is liable to get hard and crack. 
 After lining the inside of the tank with asphaltum, the out¬ 
 side may be painted, or it may be brushed over, with ordi¬ 
 nary asphaltum. 
 
 Covers for tanks, which are necessary to keep out dust, 
 etc., may be made of any ordinary wood, and should be the 
 exact width and length of the tanks. It is well to brush 
 the inside of the lid with the prepared asphaltum. Fig. 13 
 shows the cover for the tank. 
 
 To suit various sizes of work it may be necessary to 
 make the tanks the width of two planks, in which case they 
 should be matched tightly and drawn together with four 
 rods, two at each end of the tank, with a screw and nut on 
 the ends. 
 
 Plating vats may be bought ready made, the 10-gal. size 
 
 
32 
 
 SHOP EQUIPMENT 
 
 costing about $10.00. A 15-gal. scrubbing tank costs $5.00 
 or $6.00. 
 
 For goldplating, or gilding, a crock or glazed dish may 
 be used. One holding a pint, of solution is usually large 
 enough, as the filling of a large tank with gold solution 
 would, of course, be out of the question. Another reason 
 for using the crock is that the gold solution is used hot. 
 
 The plating tank is made ready for work in the follow¬ 
 ing manner: After testing the tank carefully for leaks, 
 and calking and brushing in more asphaltum if necessary, 
 place it on wooden horses in the place assigned to it, of 
 
 which more will be said when we come to the subject of 
 shop arrangement. See that the tank is plumb and steady 
 and not to be disturbed by jostling the supports. Get three 
 pieces of brass pipe, Ft or H i n - inside diameter, for each 
 tank. They must be stiff enough to hold the anodes and 
 the articles to be plated. Set these pipes in grooves in the 
 ends of the tank, as shown in Fig. 14, and connect with 
 copper wire, carefully soldered, or connected .by brass or 
 copper clamps. 
 
 The practice of winding the wire about the ends of the 
 rods without soldering is a bad one, as the wires are apt 
 to get loose and the winding filled with dirt, making a bad 
 connection. See that all joints are well made, and solders 
 
SHOP EQUIPMENT 
 
 33 
 
 and all parts connected by clamps and under screws are 
 made clean, with broad surfaces of clean metal in contact 
 at all points. Keep the metal clean by occasionally scour¬ 
 ing it with emery paper. Perfect connections insure an 
 uninterrupted circuit and the highest economy in working. 
 
 The arrangement of the connecting rods and the tanks 
 is shown in Fig. 15. On the positive rods AA are hung 
 the anodes, composed of the metal to be dissolved by the 
 action of the electric current, and on the negative rod, B, 
 are suspended, by hooks of No. 8 gauge copper wire, or by 
 the regular slinging hooks that come for this purpose, the 
 goods to be plated, which are the cathodes in the electric 
 
 circuit. This figure also shows how four tanks may be ar¬ 
 ranged for different classes of work and connected with 
 three or more cells as may be needed. When a single tank 
 only is to be used, connect that tank only with the battery. 
 It should be understood, of course, that a small job re¬ 
 quires less current in amperes than a large one, and that 
 all current vised in excess of needs is not only a waste, but 
 injurious to the job on hand. 
 
 The tanks should never be left empty when not in use, 
 nor should the solutions be allowed to get foul, for if the 
 tanks get dry they are liable to warp and leak, and dust 
 and impurities in the solution will interfere with the plating. 
 
SHOP EQUIPMENT 
 
 35 
 
 TANK REGULATION 
 
 Tank regulation is an important matter in an up-to-date 
 shop where several tanks are in constant use. There is a 
 material difference in the density of different solutions, 
 which varies also as they are used, and in manipulating 
 tanks of various sizes where different solutions and differ¬ 
 ent operations are employed it becomes necessary that 
 proper regulations of the current be secured. This cannot 
 be effected by the field rheostat on the dynamo, which con¬ 
 trols the voltage at the terminals of the machine by in¬ 
 creasing and decreasing the resistance provided by the cir¬ 
 cuit, but does not affect the ampere capacity of the ma¬ 
 chine. On the other hand a rheostat placed in series with 
 the tank affects both amperes and volts, reducing the latter 
 in the proportion in which the former is cut down. There¬ 
 fore in selecting a tank rheostat it should be of a size suited 
 to the ampere capacity of the tank. Fig. 16 shows the con¬ 
 nection of two rheostats in the circuit for tank regulation. 
 In this case a dynamo is used instead of a battery to supply 
 the power. ' 
 
 SCOURING TROUGHS 
 
 The scrubbing or scouring trough may, of course, be 
 made large or small, according to the size of the shop. 
 For convenience this is made in shape like the ordinary 
 stationary wash tub, and should be of heavy dressed plank, 
 well matched and jointed. As strong potash solutions are 
 used in scrubbing, the trough or tray is sometimes painted 
 with prepared asphaltum, or lined with lead, the seams of 
 which must be wiped and not soldered. 
 
 Rabbet the bottom and sides, and bevel the front side 
 to give the required angle. Set the bottom into the sides, 
 not the sides on to the bottom. Fit the joints together 
 tightly with white lead. Use large wood screws, not nails, 
 in putting the parts together. Set a couple of horizontal 
 
36 
 
 SHOP EQUIPMENT 
 
SHOP EQUIPMENT 
 
 37 
 
 cleats 6 in. down in one end of the trough and make a 
 light tray on which to rest goods in working. 
 
 MISCELLANEOUS EQUIPMENT 
 
 A treadle lathe, scratchbrush and a bench polishing ma¬ 
 
 chine are indispensable. In a large shop these machines 
 are run by power', and the plater must be his own judge 
 as to the economy of using electricity or steam in running 
 his tools. For a small shop, it is taken for granted that 
 
38 
 
 SHOP EQUIPMENT 
 
 Fig. 20. Making a Respirator 
 
 one or two simple foot lathes will suffice to begin with, 
 and these may be bought second-hand or even built by the 
 expert mechanic. A simple form of foot-power polishing 
 machine is shown in Fig. 17, and. a power polishing and 
 buffing lathe is shown in Fig. 18. 
 
 The cleaning, polishing and buffing wheels required are 
 the following: Felt wheel; leather wheel; emery or car¬ 
 borundum wheel; cotton and flannel buffs; cotton watch- 
 case buff; long, thin felt buff for the inside of finger rings, 
 and brass-wire scratchwheel. 
 
 Among the miscellaneous equipment may be mentioned: 
 Good scales, a clock, several galvanized iron pails, wooden 
 buckets or tubs, various wood-fiber brushes, a glass funnel 
 and graduate glass, thermometer, hydrometer, Fig. 19, (for 
 measuring the specific gravity of the solutions), glue pot, 
 etc. In the way of personal equipment, perhaps a suit of 
 old clothes should not be omitted, including a stout pair of 
 high shoes. Some platers use shops with wooden soles, but 
 the floor should never -be so wet as to require such a pre- 
 
SHOP EQUIPMENT 
 
 39 
 
 caution. A good rubber apron, rubber gloves and finger 
 tips (the tips should not take the place of the gloves en¬ 
 tirely), a respirator and a pair of automobile goggles com¬ 
 plete the outfit. Remember that what may seem a useless 
 precaution may save a man from being laid up for a week, 
 or from more serious harm. 
 
 A serviceable respirator to guard the nose and throat 
 from poisonous acids and dust, may be made as follows: 
 
 Get a thin rubber ball 
 about 6 in. in diameter, cut 
 it in half, and then cut out 
 a circle 2 in. in diameter in 
 each half as in A, Fig. 20, 
 and a semicircular notch 
 in the edge Y\ in. deep, 
 
 Fig. 22. Aluminum Dipping Baskets 
 
40 
 
 SHOP EQUIPMENT 
 
 as shown at the top in Fig. B. Fasten onto one of 
 the halves a rubber band to go snugly but not tightly over 
 the head, as at C. Sew the other half of the ball at the 
 sides, which allows a space to insert a close-grained sponge 
 as shown at D. In use its appearance is shown at E. 
 When the sponge is dampened one may breathe easily 
 (through the nose always). The sponge may be easily re¬ 
 moved and cleaned. See that it is always kept moistened. 
 
 A number of stoneware crocks and kettles will be found 
 necessary, and these are to be preferred to enameled ware, 
 as the enamel wears off in a short time and the iron is then 
 attacked by the acids. A stoneware pitcher or two will 
 also be needed. 
 
 Dipping baskets of glazed stoneware are used where a 
 number of small articles have to be dipped in acid or 
 cyanide solution. Aluminum wire baskets are now made, 
 and are much lighter, but they cost four or five times as 
 much as the earthenware, which run from 50c to $2.00. A 
 stoneware dipping basket is illustrated in Fig. 21, and 
 aluminum baskets in Fig. 22. 
 
 THE PLATING SHOP 
 
 We now come to the plating shop and its arrangement. 
 Just as a kitchen may be comprehended in a chafing dish 
 or a hotel outfit, so the plating shop may begin with a 
 single-cell battery and a glass jar or stoneware kettle, and 
 grow up to an establishment covering an acre of ground. 
 
 We will suppose that the beginner starts with a small 
 shop. This should be in the business part of the city, but 
 not where there is much smoke. A good business street in 
 a growing suburb is a good location, for, as an old silver- 
 plater wisely says, “the trade should go to the people, and 
 not expect the people to come to the trade.” The . shop 
 should have two rooms—one for the plating room and one 
 for the polishing room. If there is a small room for an 
 office, so much the better. One large room might be used 
 by dividing it with a partition. The solutions, tanks, etc., 
 
SHOP EQUIPMENT 
 
 41 
 
 must be carefully protected from dust, and this cannot be 
 done if the polishing and cleaning are done in the same 
 room with the tanks. 
 
 Light and ventilation are prime requisites. Artificial 
 light will not supply the place of diffused sunlight. A 
 northern exposure is to be preferred, and a good skylight 
 is a great advantage. The examination of the goods and 
 the solutions, while the various processes of the work are 
 going on, and the care of the machines, to say nothing of 
 the processes of polishing, etc., cannot well be undertaken 
 without plenty of sunlight. At the same time care must 
 be taken to protect the tanks from the direct sunlight, which 
 decomposes all plating solutions. This is why a northern 
 exposure is preferred. The vats and baths should be 
 covered with canvass or wooden covers when not in use, to 
 exclude both dust and light. 
 
 The shop should be well ventilated, through an ample 
 opening in a skylight or by a fan in the chimney or air 
 shaft. The gases and fumes of some of the chemicals used 
 are highly poisonous, and care should be taken that they 
 are carried off rapidly. Have a closet for the stock of 
 acids and chemicals and keep them there properly labeled, 
 under lock and key. In another cupboard keep antidotes 
 for poisons, as given in detail in Chapter X. Handy 
 cabinets, in which tools may be kept, may be made from 
 soap boxes or other boxes. 
 
 The floor should be tight and smooth, and kept dry. 
 There is no need of having a plating shop wet and sloppy, 
 and if there should be tenants below, the drip might cause 
 trouble. Use plenty of sawdust, and never let pools of 
 water stand on the floor. When sweeping, be sure to cover 
 all plating tanks, acid baths, etc., and use damp sawdust to 
 gather the dust. Steam heat is almost a necessity on ac¬ 
 count of its regularity and freedom from dust, gas and 
 smoke. The temperature of the shop should be 6o° to 
 65° F. 
 
42 
 
 SHOP EQUIPMENT 
 
SHOP EQUIPMENT 
 
 43 
 
 Fig- 24. Circular Scratchbrushes 
 
 In arranging the shop it is well to get the aid of an ex¬ 
 perienced plater in whom confidence can be placed. No 
 directions can be given in print that would cover all condi¬ 
 tions of location of the various machines and apparatus, 
 the arrangement of light, and the amount of equipment to 
 be carried. A general plan of shop arrangement is shown 
 in Fig. 23. 
 
 POLISHING TOOLS AND POWDERS 
 
 Scratchbrushes are made of both steel and brass wire 
 and are used on a lathe for the first process of cleaning up. 
 The stiff brushes may be used with emery, carborundum 
 and other abrasives to grind off old silver and smooth the 
 
 Fig. 25. Lathe Brush for Insides Fig. 26. Cup-Shaped 
 
 of Goblets Brush for Watch Cases 
 
SHOP EQUIPMENT 
 
 47 
 
48 
 
 SHOP EQUIPMENT 
 
 rough surfaces of castings, while the finer brushes of 
 crimped wire may be used for gold work. 
 
 Figure 24 shows two styles of platers’ circular scratch- 
 brushes for work on the lathe. A lathe brush for the in¬ 
 side of goblets is shown in Fig. 25, while Fig. 26 shows a 
 cup-shaped brush for watch cases. Another brush for in¬ 
 side work is shown in Fig. 27, and an end brush in Fig. 28. 
 A tampico-fiber brush for the lathe is shown in Fig. 29, and 
 a beveled bristle brush in Fig. 30. 
 
 In order to produce the satin finish or sand-blast effect 
 on German silver, aluminum, brass, steel or other metal, 
 special brushes are used. As will be seen, in Fig. 31, the 
 wires are loosely hung to the hub and are allowed to whip 
 the work. The common types of hand brushes are illus¬ 
 trated in Figs. 32, 33, 34, 35 and 36. 
 
 Buffs or bobs may be used on the same lathe as the 
 scratchbrush or emery wheel, on the right-hand end of the 
 spindle. They are used both for polishing new work and 
 for finishing plated goods. Buffs are in endless variety, of 
 felt, leather, canvas and muslin. The usual style of stitched 
 muslin and cotton wheel is shown in Fig. 37. When the 
 
 term “calico” is used in 
 English or German tech¬ 
 nical books, unbleached 
 muslin is referred to. 
 Swansdown calico is a soft, 
 unbleached muslin. Figure 
 38 illustrates the canvas 
 wheel. A “bull-neck” leath¬ 
 er wheel is shown in Fig. 
 39 - 
 
 Emery, corundum, or car¬ 
 borundum wheels, illustrat¬ 
 ed in Fig. 40, are used on 
 the lathe for grinding down 
 new goods, removing old 
 plating, etc. The use of the 
 
SHOP EQUIPMENT 
 
 49 
 
 Fig. 43. Correct Method of Holding Article in Polishing or Buffing 
 
 emery wheel is usually followed by the bull-neck leather 
 wheel, walrus, and canvas. 
 
 Walrus wheels are made of tanned walrus or seahorse 
 hide, which from its extreme toughness is regarded as indis¬ 
 pensable in certain classes of work. Such a wheel is shown 
 in Fig. 41, and the compressed-leather wheel in Fig. 42. 
 The right method of holding the article when polishing or 
 buffing is illustrated in Fig. 43. Let the wheel run so that 
 the bottom of the wheel goes from you. 
 
 Pumice, powdered, is used with a scrub brush and lye 
 solution to clean iron and steel goods and to remove dirt 
 and grease. The best pumice comes from Italy. 
 
 Emery or carborundum is used in polishing old table¬ 
 ware. It is glued on leather or felt wheels to grind out 
 
50 
 
 SHOP EQUIPMENT 
 
 rough places in all kinds of work. Turkish emery is gen¬ 
 erally used by electroplaters, and an emery glue may be 
 bought already prepared. 
 
 Silver sand is used to remove the scum in silverplating 
 in the same way that the wire scratchbrush is used. Places 
 that cannot be reached with the scratchbrush, as the inside 
 of rings, cups and hollow-ware, are treated with wet sand 
 on a brush or bob. 
 
 Tripoli is a fine siliceous earth which is made into a 
 grease composition. It is used on all kinds of wheels except 
 cotton flannel, bristle and wire brushes, and is good for 
 cutting down and smoothing all kinds of metalwork. To 
 apply tripoli, hold it against the wheel while the latter is 
 running. 
 
 Rouge is a red powder and is practically the same as 
 iron rust which has been heated to drive off the water 
 that is combined with it. It is applied to wheels to brighten 
 and color up all kinds of work, both before and after plat¬ 
 ing. It is used in the same way as tripoli. French rouge 
 is the best. 
 
 Crocus is a deep yellow or a red powder, the oxide of 
 some metal (usually iron) which has been calcined at a 
 great heat. It is a little coarser than rouge, and is used in 
 the same way. 
 
 A pure, soft lime, free from grit, is used as a polisher. 
 Vienna lime is used in this country and Sheffield lime in 
 England. It comes in 15-lb. cans. 
 
 Litmus paper should always be kept on hand for test¬ 
 ing solutions. Blue litmus turns red if the solution contains 
 free acid, and red litmus will turn blue if free alkali is 
 present. Keep it in a tight tin box. 
 
 Whiting is chalk, ground to a fine powder. It is an 
 excellent polisher, used after pumice. 
 
 Rotten stone is a decomposed silica derived from certain 
 
SHOP EQUIPMENT 
 
 51 
 
 limestones, and is used as a polisher. The best comes from 
 England and is as fine as flour. 
 
 MECHANICAL PLATING 
 
 Where a large number of small articles are to be electro¬ 
 plated, the time required in stringing them on wires for 
 hanging in the tank becomes a considerable item. To do 
 away with this expense, a special tank has beep brought 
 out. This tank has a perforated cylinder in which a large 
 number of small articles may be placed and which is kept 
 in constant rotation by a belt. 
 
 Fig. 44. Mechanical Plating Tank 
 
 I he construction of this mechanical plating tank is shown 
 in big. 44. The articles to be plated are poured into the 
 cylinder as shown in Fig. 45, and the anodes of copper, 
 nickel, or whatever the coating is to be, are hung in parallel 
 rows on each side of the cylinder. Special curved anodes 
 are used, making the operation quick and effective. The 
 
52 
 
 SHOP EQUIPMENT 
 
 cylinder should be rotated at from io to 20 revolutions per 
 minute, two speeds usually being provided for by a stepped 
 pulley outside the tank. 
 
 Several advantages are claimed for these “plating bar¬ 
 rels,” and the results seem to bear out the claims made for 
 them. The principal feature is, of course, the labor saved 
 in preparing the articles. This is strikingly shown by a 
 comparison of Fig. 45 with Fig. 46. In plating bronze or 
 
 brass on steel in stationary tanks, there is a tendency to a 
 deficiency or an excess of the copper, but this seems to be 
 overcome with the mechanical platers. Further, the deposit 
 of metal seems to give a more even and more protective 
 coating with a somewhat smoother finish. 
 
 Any small work, such as small automobile and bicycle 
 parts, bolts, nuts, screws, sewing-machine and typewriter 
 parts, and the like, are particularly adapted for mechanical 
 plating. 
 
CHAPTER IV 
 
 CLEANING GOODS BEFORE PLATING 
 
 \X^HEN GOODS are received, make a careful tally, 
 v * giving kind, number, marks, etc., with directions as 
 to plating. The first operation is the cleaning of the goods. 
 In plating, it should be carefully understood that “cleaning” 
 means making the goods chemically clean, not ordinarily 
 clean, as an entirely unobstructed surface of metal must be 
 exposed to the solution to insure the thorough adhesion of 
 the particles of metal to the cathodes (or goods to be 
 plated in the tank). It is necessary, therefore, to free the 
 surface of the goods, including every line and indentation, 
 from every trace of foreign matter of any kind, whether in 
 the form of rust, verdigris, tarnish, or any other kind of 
 corrosion, or in the form of oil, grease, lacquer, sweat, 
 etc. The touch of a finger on the prepared surface is suffi¬ 
 cient, for instance, in silverplating, tc- cause the silver to 
 strip off frcm the spot when the scratchbrush or the bur¬ 
 nisher is applied. 
 
 The workman must also see that all deep scratches, dents 
 and cracks are removed before the goods are put in the 
 tanks, and that all necessary repairs are made, avoiding an 
 excess of solder, and that all previous coats of silver or 
 nickel are removed and the surface polished. 
 
 CLEANSING SOLUTIONS 
 
 To remove grease, etc., first plunge the goods in hot lye, 
 using y 2 lb. of caustic potash or soda to 2 gal. of water; 
 then plunge them in hot water and give a final rinsing in 
 cold water, when they are ready to be treated for rust and 
 corrosions. If there is no steam coil, the lye and water 
 kettles may be firmly set over a gas furnace. 
 
 Rust, verdigris and other metal oxides are removed by a 
 
 53 
 
54 
 
 CLEANING GOODS BEFORE PLATING 
 
 pickle of a dilute mineral acid. A mixture of equal parts 
 of sulphuric acid and water makes a good cleaning bath for 
 these oxides. String the articles on a wire and plunge them 
 in the mixture for a few minutes. Use the scratchbrush 
 and wash, and if the stain is not removed, repeat the 
 process. 
 
 The light tarnish may be removed by dipping in a strong 
 solution of cyanide of potassium, say, 2 oz. of cyanide to 1 
 gal. of water, with the addition of a few drop's of liquid 
 ammonia. For the oxides of copper and zinc, use a mix¬ 
 ture of 1 part of sulphuric acid in 20 parts of water, and 
 if the stains are deep and fail to come off, strengthen the 
 pickle. 
 
 For rust on iron or steel, use a pickle of 6 parts sul¬ 
 phuric acid, 1 part muriatic acid, and 160 parts of water. 
 The goods are dipped in this solution from 15 to 30 seconds 
 or longer if necessary. For oxides of lead and tin. includ¬ 
 ing britannia ware, pewter, etc., use a hot lye solution. 
 
 Lacquered goods should be steeped for a few minutes in 
 a hot alkali solution. They should then be well brushed 
 with an old scratchbrush and rinsed in hot water. 
 
 The next process after cleaning, if the job is one of re¬ 
 plating silver, is to remove all the old silver plate. For 
 this purpose a stripping solution is used. 
 
 STRIPPING SOLUTION 
 
 To one gallon of commercial sulphuric acid, add 12 oz. 
 of potassium nitrate (saltpeter) and heat to 150° Fahr. 
 Do not put soft metal, such as britannia, lead, pewter, tin, 
 zinc, etc., in this solution, or any wet articles, as they would 
 be eaten by the acid. Fifteen minutes is usually long 
 enough to leave goods in this pickle. After the old plating 
 is removed, the surfaces of the articles to be plated should 
 be well brushed in water with a stiff brush to remove loos¬ 
 ened dirt from crevices. This process may reveal several 
 imperfections in the way of dents and scratches which 
 should be taken out on the polishing lathe or by the careful 
 
CLEANING GOODS BEFORE PLATING 
 
 55 
 
 use of the hammer. After polishing, the goods should be 
 again plunged into the alkali pickle to remove the film of 
 grease which was put on in handling. The dipping, how¬ 
 ever, adds a thin coat of black oxide, which must be re¬ 
 moved by bright dippjng or scouring. For this purpose the 
 article is held on the dipping tray with the left hand, while 
 the article is brushed with a wet brush dipped in pumice 
 powder until every trace of oxide is removed. Then rinse 
 in water, and it will be quite clean and ready for the plating 
 tank. 
 
 The article should not be touched again with the hand, 
 but should be picked up with a wire hook, and, if to be 
 silverplated, dipped into the necessary bath, again rinsed in 
 clear water, and put into the plating tank. 
 
 If the goods are of iron, steel or zinc, they should be 
 copperplated before the silver is put on. Many platers do 
 this with soft-metal goods also, getting a better job by this 
 process. 
 
 To recover the silver from the stripping solution, add 
 the worn out “strip” slowly to several times its bulk of cold 
 water. Allow it to settle, and decant the clear solution. To 
 this is added chloride of sodium (common salt), until the 
 silver chloride is no longer precipitated. Chloride of silver 
 settles very rapidly. The clear solution may be thrown 
 away, and the precipitated chloride of silver is then washed 
 several times with boiling hot water to remove any chloride 
 of lead that may be present. 
 
 This silver chloride may be used for a “striking solution.” 
 
CHAPTER V 
 
 COPPERPLATING 
 
 T HE PROCESS of copperplating will be treated first, 
 as it is a preliminary to much of the nickel, silver and 
 gold plating, for the reason that these metals, especially 
 silver, deposit more easily and firmly on copper than on 
 iron, steel or soft metals, which take copper easily and then 
 present a good surface for the finishing metal. When rough 
 goods are well polished and coppered, they will turn out a 
 good job in the nickel or silver plating tank. If repairs are 
 necessary, they should be made smoothly by soldering them 
 over and polishing them the same as the coppered surface. 
 
 When the goods have been polished, as previously de¬ 
 scribed, they are hung on the suspending wires, plunged into 
 the potash pickle, rinsed, brushed with powdered pumice 
 stone or whiting, and then rinsed again. If the articles are 
 copper or brass or copperplated they are to be given a dip 
 in the cyanide dip. For steel or iron use dilute sulphuric 
 acid dip, after which they are thoroughly rinsed and hung 
 in the plating vat. 
 
 COPPERING SOLUTION 
 
 The copper solution for the plating tank is made up 
 as follows: Dissolve in a glazed jar or crock 8 oz. 98 
 % cyanide of potassium in 1 gal. of water and add 
 4 oz. of dry carbonate of copper. This solution should be 
 made up cold. If hot water is used it will change the prop¬ 
 erties of the copper carbonate. A portion of the powder 
 will remain undissolved, and may lead to the belief that the 
 chemicals are impure. 
 
 For the anode plates, pure copper is employed, with a 
 surface somewhat in excess of the surface of the goods to 
 be plated. Too much anode surface is likely to give a hard, 
 
 56 
 
COPPERPLATING 
 
 57 
 
 dark deposit, especially if the current is high. Too rapid 
 a deposit should be avoided. 
 
 In placing the articles in the vat, or rather when rinsing 
 them in the potash pickle, they are hung on a copper-wire 
 “S” hook. See that all bubbles are washed off when hang¬ 
 ing the goods in the vat. If the goods are gently moved 
 during the plating, the deposit is made brighter. 
 
 Ten or fifteen minutes is usually long enough to secure a 
 good plating. Take out the goods, rinse in cold and then 
 in hot water, and dry in hot sawdust. They are then ready 
 for buffing. 
 
CHAPTER VI 
 
 NICKELPLATING 
 
 F OR NICKELPLATING, the goods are prepared as for 
 any other work, and if treated with a thin coat of cop¬ 
 per, as described in the last chapter, the nickelplating will 
 be brighter and more durable. 
 
 Be very particular about having the goods properly 
 dipped before putting them through the plating bath. As 
 they come from the polishing lathe, although apparently 
 bright, they are covered with a thin film of grease, invisible 
 to the eye, but sufficient to prevent the nickel in the solu¬ 
 tion making contact with the metal surface of the goods. 
 This would cause blister, which would show in the scratch- 
 brushing. To avoid this, rinse the goods well in the lye and 
 scour with powdered pumice stone or whiting, for fine 
 work, holding them with a dry linen towel well powdered. 
 When well scoured, rinse off the powder or whiting in 
 clear water, plunge the articles in the muriatic-acid dip 
 described elsewhere, rinse and hang in the copperplating 
 vat for the preliminary coating of copper, or place directly 
 in the nickel vat if the coppering is to be dispensed with. 
 If the goods have been coppered, examine the work under 
 a good light, rinse and place in the nickel vat. 
 
 It is of no advantage whatever, but rather a disadvantage, 
 if the goods have been previously nickelplated, for all the 
 old nickel must be stripped before plating with a new coat. 
 This is due to the peculiar action of nickel in the plating 
 solution, as it refuses to make a permanent union with a 
 nickel surface, even one newly plated and polished. If the 
 goods are in the f-prm of tubes or plain flat surfaces, the 
 nickel may be taken off with an emery wheel; otherwise it 
 must be put into the acid stripping bath. 
 
 58 
 
NICKELPLATING 
 
 59 
 
 NICKEL-STRIPPING BATH 
 
 In a glazed jar put, in the order given below, ^4 gal. of 
 commercial nitric acid and turn in 2 gal. of strong sulphuric 
 acid slowly, stirring it at the same time with a smooth hard¬ 
 wood stick. Be careful not to let it spatter out on the hands 
 or face, as the acid is very corrosive. It is best to wear a 
 
60 
 
 NICKELPLATING 
 
 mask and rubber gloves when handling this or other acids. 
 When the mixture cools, pour it in a stoneware vessel, 
 which should be protected by a good cover. Water in this 
 bath will cause pitting. 
 
 To strip nickel goods, clean them properly as before di¬ 
 rected, plunge them in the al¬ 
 kali solution, and then into the 
 hot-water tank. They are 
 then thoroughly dried and 
 hung, by means of copper wire 
 in the stripping bath. The 
 process will require several 
 hours time, according to the 
 amount of nickel to be re¬ 
 moved. The goods can be 
 drawn up and inspected as 
 often as necessary to see how 
 the operation is proceeding. As 
 soon as the nickel is entirely 
 stripped, take out the goods 
 and rinse in clear cold water, 
 again in hot water, and dry in 
 hot sawdust. 
 
 NICKEL SOLUTION 
 
 Dissolve double sulphate of 
 nickel and ammonia in the 
 proportion of % lb. to the gal¬ 
 lon of water. Use a glazed 
 jar or crock, and put the 
 nickel salts in a sack and sus¬ 
 pend it by a wire in the top 
 of the vessel. Use cold water 
 to dissolve the salts. Be par¬ 
 ticular to use only the best 
 quality of nickel salts, which 
 give a brilliant, silver-like 
 
NICKELPLATING 
 
 61 
 
 effect. Use 90 to 92 % pure nickel for the anodes. Sev¬ 
 eral special shapes of nickel anodes are shown in Figs. 47, 
 48, 49, 50 and 51. In placing the work in the vat, put in 
 the larger articles first, if there are several sizes, and do not 
 attempt to plate different metals, as steel and britannia, in 
 the same tank, as these metals require different voltages. See 
 that sufficient anode surface is used, else the solution be- 
 
62 
 
 NICKELPLATING 
 
 comes too acid. For ironwork, a slight acidity does no 
 harm, and is rather a benefit. The degree of acidity may 
 be tested by litmus paper, an acid solution turning blue lit¬ 
 mus paper to red and an alkaline solution turning red lit¬ 
 mus paper to blue. A special hydrometer, called a “nickel- 
 ometer” is used by nickelplaters to test the solution. This 
 solution should not register more than 7 on the ffickel- 
 ometer. 
 
 To correct the excess acidity, add liquid ammonia in 
 small quantities until the solution ceases to redden blue lit¬ 
 mus paper. 
 
 If the solution becomes weak and fails to deposit white 
 nickel it should be strengthened by adding either single or 
 double nickel salts. 
 
 The length of time in which the goods are to remain in 
 the vat depends upon conditions. If previously coppered, 
 not so long a time is required, and, similarly, if the solu¬ 
 tion is strong and there is a good current and sufficient 
 anode surface, less time is required. Nickel is deposited 
 at the rate of approximately 17 grains per ampere-hour. 
 Best results are obtained with a voltage of 2*4 to 2* 4 , 5 
 amperes per square foot of actual surface exposed. Watch 
 the current, and after a thin coating of metal has been de¬ 
 posited, reduce the voltage to a point where the work is 
 not “burned” at the lower edges. Leave the goods in the 
 bath or ^4 of an hour, according to the class of work 
 to be done. 
 
 When the goods have taken on the desired thickness of 
 metal, lift them out of the solution by the slinging wires, 
 rinse in cold water and then in the hot-water tank and dry 
 off quickly in hot sawdust. Work quickly and be sure the 
 rinsing and drying are thoroughly done, as exposure to the 
 air with the plating solution causes oxidation in the form 
 of blotches which buffing cannot remove. The goods, as 
 •taken from the vat, have a dull gray appearance, and may 
 range from a creamy white to a dull yellowish hue. A 
 
NICKELPLATING 
 
 G3 
 
 dirty gray indicates an inferior solution, or perhaps a too 
 rapid deposit in the bath. 
 
 After thorough drying in sawdust, the goods are well 
 buffed with Vienna lime, tripoli or rouge. This may be 
 done either by hand or on the polishing lathe, using soft 
 muslin buffs, and' a small brush to reach the crevices. Do 
 not use the brass scratchbrush, as the brass will make a de¬ 
 posit on the nickel which is difficult to remove. 
 
 Imperfections in the plating, such as an occasional blis¬ 
 ter, may be removed by buffing and sponging the spot with 
 the alkali dip, to cleanse it, and applying a sponge wet with 
 the nickel solution and containing a piece of nickel anode 
 connected with the battery. Connect the goods with the 
 negative pole of the battery as if it were in the plating tank, 
 and let the current pass through for as long a time as if 
 the goods were in the tank. This process can only be re¬ 
 sorted to for an occasional patch. If the whole work is 
 imperfect, it will have to be stripped and replated. 
 
 The plater cannot be too particular in finishing the goods 
 and securing a high polish, as this is what chiefly gives 
 satisfaction to the customer, who can only judge of the 
 wearing quality of the work by experience. A variety of 
 polishing brushes and buffs should be used, and all rough¬ 
 ness and clouds removed. A basil-leather buff (bark- 
 tanned sheepskin) with fine tripoli imparts a fine polish, if 
 finished with canton flannel and a little rouge. Much rouge 
 is objectionable on account of the dust. Go over all the 
 surface thoroughly, reaching all the holes and angles, and 
 secure a bright, uniform polish. Beware of abrasives and 
 too much “elbow grease,” as such treatment is apt to cut 
 through the nickel skin and ruin the job. The process of 
 polishing emphasizes the importance of a good thick coat 
 of nickel in the plating bath (and the same is true of all 
 plating processes), as it allows for more effective finishing 
 without spoiling the job and necessitating stripping and re¬ 
 plating, with consequent expense and loss of time. 
 
64 
 
 NICKELPLATING 
 
 TO PREVENT NICKEL FROM TARNISHING 
 
 Nickelplated work after exposure to the air for a few 
 months, especially in a damp climate, is apt to tarnish, caus¬ 
 ing dissatisfaction to the customer. The tarnish is caused 
 by the oxidation of the minute particles of iron contained 
 in the nickel, the iron being added to the metal in the anode 
 for the purpose of “softening” it or making it more soluble. 
 Good nickel contains from per cent to 5 per cent of iron, 
 and the deposit is all the whiter on this account. 
 
 To prevent the discoloration in fine goods they may be 
 run through an acid pickle to remove the iron on the sur¬ 
 face. The pickle is made by adding 1 gal. of muriatic acid 
 to 4 gal. of water. Sulphuric acid may be used, but it js 
 not a good solvent. After the articles are plated, rinse in 
 cold water and plunge them a moment in the pickle, which 
 is warmed to 8o° to ioo° F. Let them remain a few sec¬ 
 onds, rinse in cold water, then in hot water, and finally 
 soak in a hot whale-oil soap solution for 15 or 20 minutes. 
 
CHAPTER VII 
 
 SILVERPLATING 
 
 CjlLVERPLATING is the rock on which many an ama- 
 ^ teur has been shipwrecked. Misled by the fetching ad¬ 
 vertisements of “silverplating outfits/’ with pretty much 
 everything, including a princely revenue, “free,” he invests 
 all his spare dollars and runs in debt, without even posting 
 himself on the A B C of the business, and finally throws it 
 over, sells the outfit for junk, turns his tanks into chicken 
 coops and retires from business, a sadder and wiser man. 
 The fact is, silverplating, and all electroplating, is like fish¬ 
 ing as described by Isaac .Walton: “an art to be learned by 
 practice or long observation, or both.” The silverplater 
 should begin in a very small way and advance by degrees, 
 studying every step carefully as he goes, and mastering' 
 the plater’s “art and mystery” with as little loss by error 
 and bad work as possible. 
 
 We will suppose that the goods have been cleansed and 
 polished and made ready for the plating tank, as previously 
 described, including the preliminary copper coating, and 
 are now ready for the silvering process. Careful platers, 
 before putting the goods into the silvering tank, transfer 
 them from the coppering solution to an alkaline mercury 
 solution for a few seconds, to give them a film of mercury, 
 which greatly increases the attraction of the goods to the 
 metal in the silver solution and secures a good wearing 
 coat. This is called “quickening.” 
 
 ALKALINE QUICKENING SOLUTION 
 
 In a stoneware vessel, dissolve nitrate of mercury in wa¬ 
 ter and then add cyanide slowly, stirring with a stick. The 
 quantity of mercury should be governed by the weight or 
 thickness of the metal to be plated. For thin metal from 
 
 65 
 
66 
 
 SILVERPLATING 
 
 Ys to 54 oz. to the gal. would be sufficient, but for heavier 
 articles this can be doubled with safety. When the liquid 
 is clear, dilute with distilled water to make i gal. Keep 
 in a stoneware jar, securely covered. Be sure to remember 
 that cyanide is a deadly poison and cannot be too carefully 
 used. It should not be touched with the hand or the fumes 
 inhaled. 
 
 Accurately weigh the goods in the platers.’ scales, taking 
 care not to touch the former with the hands, and place them 
 immediately in the silverplating tank, using hooks of silver 
 wire. The tank has been made ready with the proper 
 amount of solution, and the anodes adjusted with due re¬ 
 gard to the proper amount of surface to be treated, remem¬ 
 bering that the anode surface should be slightly in excess 
 of the surface of the cathodes. The anodes should be of 
 pure annealed silver, not standard or coin silver. 
 
 English and German platers prefer to make their own 
 solutions from the metal, but it is better, especially for the 
 beginner, to take as few chances with the manipulating of 
 chemicals as possible, and to buy the prepared salts (that is 
 to say, combinations of acids and metals, as nitrate of cop¬ 
 per, cyanide of silver, etc.) and make the solutions there¬ 
 from. The surest way for the beginner is to obtain his 
 solutions from the manufacturer. It may cost a little more, 
 but it saves time, work and money in the end to put as 
 much of the burden as possible on the big factories. 
 
 SILVER SOLUTION 
 
 To get the best results in plating, use two baths or 
 “strikes” before the third or final plate. The first solution 
 is made as follows: Potassium cyanide, 2 lb.; silver chlo¬ 
 ride, 154 dwt; in enough water to give a density of 20° to 
 24 0 Baume. The silver chloride may be made by dissolv¬ 
 ing 1 oz. of fine silver in nitric acid and precipitating with 
 muriatic acid or common salt and then washing. Instead 
 of a silver anode, a large copper anode is preferred, as it 
 adds enough copper to the solution to make a strong de- 
 
SILVERPLATING 
 
 67 
 
 posit while giving no coppery tint. The pressure used 
 should not be above 2 volts. Move the articles about as 
 they hang on the rods, to get a good deposit. In five or six 
 minutes they should have a bright straw-colored deposit,, 
 and may be taken out and brushed. 
 
 The second bath is the regulation silver “strike” of 8 oz. 
 of potassium cyanide and y 2 oz. of silver chloride in enough 
 water to make 1 gal. of solution. Use a pure silver anode. 
 Four or five minutes in this bath should be sufficient. 
 
 The goods are now ready for the final plating. For this 
 a solution is made of 6 oz. of potassium cyanide and 3 oz. 
 of silver chloride to 1 gal. of water. Dissolve 2*4 oz. of fine 
 silver in dilute nitric acid and convert into chloride in the 
 usual way. Then dissolve in enough strong cyanide solu¬ 
 tion to take it up, and add water enough to make 1 gal., and 
 dissolve in it i l / 2 oz. of cyanide to give an excess of free 
 cyanide. This solution will show 7 0 or 8° Baume. 
 
 STRENGTH OF SOLUTION 
 
 An ounce of . silver cyanide contains about 0.753 °f an 
 ounce of pure silver, and 132.8 oz. of silver cyanide, con¬ 
 tain approximately 100 oz. of silver. Knowing the quantity 
 of silver cyanide used, and the number of gallons of solu¬ 
 tion, the strength of the latter is easily calculated. The 
 solution may vary from 2 to 6 oz. of silver to the gallon, 
 but should not fall below the former figure. A weak solu¬ 
 tion will work slower than a strong solution, and will re¬ 
 quire a higher voltage. The amount above provided for is 
 merely experimental and may be used for small articles like 
 a watch case, in a stoneware vessel, using a single Smee or 
 Daniell cell. 
 
 A battery of 4 or 6 cells, gallon size, would make a good 
 practical working- outfit for silverplating, and could be so 
 connected as to give an e. m. f. of 4 to 6 volts, which would 
 be sufficiently strong for a solution such as above described, 
 
68 
 
 SILVERPLATING 
 
 with sufficient anode surface. Best results are obtained at 
 y 2 to i volt, 2 amperes per square foot. It should be re¬ 
 membered that the stronger the solution and the larger the 
 anode surface, the less resistance is offered and the less 
 voltage is required. 
 
 The anodes should throw off silver at a rate proportion¬ 
 ate to the silver deposited. In other words they should 
 feed the solution and prevent it from becoming impover¬ 
 ished. This they are only able to do while there is free 
 cyanide in the solution. Exposure to sunlight and air 
 causes the cyanide to form a union with the carbon dioxide 
 in the air, with a resultant loss of free cyanide in the solu¬ 
 tion. This is occasionally supplied by adding a few drops 
 of cyanide solution and stirring the solution in the tank. 
 No other chemicals whatever should be added to the 
 solution. 
 
 The anode rod should be moved about in the solution 
 occasionally, to aid the process of electrolysis. In large 
 shops, the anode rods are attached to a jig frame which is 
 kept in motion. In the same manner the cathode rods 
 should be occasionally jarred to prevent the formation of 
 bubbles or scum. 
 
 A lack of sufficient free cyanide is indicated by a coating 
 of black slime on the anodes, though this may be caused 
 also by dust and dirt in the solution if it is allowed to 
 stand many days before being used up. The cause may be 
 detected by a careful examination of the anodes. An ex¬ 
 cess of cyanide causes the silver to be deposited too rapidly, 
 as shown by the rough surface and the ragged edges of the 
 anodes. 
 
 The plating tanks should be covered when not in use, 
 and never exposed to strong sunlight. If the shop is 
 located in the neighborhood of factories, coal yards or rail¬ 
 roads (a location which should be avoided if possible), 
 there will be more or less dust and soot, and the tanks will 
 
SILVERPLATING 
 
 69 
 
 get foul if the solution is not frequently renewed and the 
 tanks cleaned. 
 
 The time to be allowed goods in the plating tank depends 
 upon the strength of the solution, the current and the thick¬ 
 ness of the coat desired. If the external resistance (of the 
 wires, anodes and solutions) is high, or if the anodes are in 
 bad condition, the wires small and the solution weak, the 
 amount of silver deposited will be lessened by these causes. 
 
 The anodes, it should be remembered, feed the solution 
 in proportion as the metal it contains is deposited on the 
 cathodes. If the anodes, therefore, are of sufficient sur¬ 
 face, and in good condition, that is, kept from accumulating 
 a slime which prevents them from throwing off their metal, 
 the solution should last indefinitely. It should, however' 
 be occasionally taken out and filtered. 
 
 An old rule in silverplating is to allow a current of 2 
 amperes to each 100 sq. in. of surface to be plated, and 
 then remove the goods and weigh to ascertain the quantity 
 of silver deposited in an hour. By watching the deposit 
 carefully the plater will soon become familiar with the 
 changes that occur under varying conditions. In two or 
 three minutes after placing them in the bath the goods 
 should take on the whiteness of the anode plates and become 
 beautifully frosted with grains of silver. If the deposit 
 turns to gray and bubbles of gas arise from the slinging 
 wire, it is an indication that the deposit is going on too 
 fast, which may be corrected by increasing the resistance 
 or reducing the current. If the deposit assumes a bluish 
 tinge, it is an indication of weakness of current or of solu¬ 
 tion, in which case the anodes may be moved up closer to 
 the goods, or, if necessary, a higher voltage may be used. 
 
 Beware of doctoring the solutions with brightening com¬ 
 pound or any other chemical than those named in the direc¬ 
 tions given on another page for preparing the solutions. 
 An occasional visit to other plating shops would be likely 
 
70 
 
 SILVERPLATING 
 
 to greatly increase the beginner’s stock of knowledge, and 
 perhaps save him some costly experience. 
 
 When the goods have remained a sufficient length of time 
 in the plating tank and the examination shows a frosty 
 coating of dead white silver they should be taken out, rinsed, 
 dried in hot boxwood sawdust and polished. Great care 
 should be used in every stage of the work. The rinsing 
 should be done in clear soft water, used hot, and the drying 
 in clean boxwood sawdust, as this is free from injurious 
 acids or resins, which, if present, would stain the silver. 
 See, too, that the sawdust is dry but not charred. The 
 article to be polished is then washed in warm mild soap¬ 
 suds, rinsed in running water and dried in hot air. The 
 article must be handled carefully, as the matt or frosted 
 surface is easily tarnished. 
 
 The appearance of the newly plated goods before polish¬ 
 ing is that of a frosted or cream-white surface. Should 
 they have a yellowish tinge when taken from -the vat, 
 plunge them immediately in a warm dilute solution of potas¬ 
 sium cyanide, rinse and dry as above directed. Silver 
 goods should not be put on the brass wire scratchbrush, as 
 it makes them brassy. Use a wood-fiber brush and then a 
 soft muslin rag with rouge composition. Give the goods 
 an even, equal pressure on all parts, without scrubbing hard 
 on one spot. Move the article about from side to side on 
 the rag and do not let it get heated. When a good bright 
 polish has been put on, wash out the rouge, using hot, 
 soapy water and a soft wool rag. Rinse in hot, clear water 
 and dry, and then mop again with a soft swansdown mus¬ 
 lin rag. Never put rags or mops down on a bench where 
 they will gather dust or grit, but keep them in tightly 
 covered boxes. 
 
 If the silver coating blisters under the polishing, there is 
 nothing to do but strip it as directed elsewhere, and replate. 
 
 A number of small articles, such as buttons, buckles and 
 the like, may be plated without being separately slung on 
 
SILVERPLATING 
 
 71 
 
 wires, by placing them in an aluminum basket and shaking 
 them about during the process. They may be dipped in 
 the stripping acid, rinsed and dried in the same manner. 
 It is a difficult process to connect the basket with the 
 cathode rod and to keep the contents shaken up in an ordi¬ 
 nary plating tank, but it may be done by an expert. A spe¬ 
 cial plating machine, something like a barrel churn, is made 
 for this sort of work and has been described before. 
 
 REPLATING STEEL TABLE KNIVES 
 
 The following simple and practical method of replating 
 old steel table knives is given by an expert: 
 
 The knives are first examined as to condition and badly 
 worn or pitted ones are thrown out. The rest are cleaned 
 in a hot solution of soda or potash. The silver is then 
 stripped in a solution of i lb. of potassium cyanide and i lb. 
 of caustic soda in i gal. of water, in a plating tank. The 
 knives are hung in a bunch as an anode by an iron wire, 
 and a piece of cleaned sheet steel is used for the cathode, 
 this operation being the exact reverse of plating. A strong 
 current up to 6 volts may be used, as the cyanide does not 
 attack the steel surface. The silver is deposited on the 
 sheet steel in the form of a spongy coating, some of which 
 falls to the bottom of the tank. The steel may be taken out 
 occasionally and brushed, and so get a better deposit, the 
 silver failing to adhere when the coating is heavy. Shake 
 the knives occasionally to facilitate throwing off the silver. 
 By filtering the solution, all the silver may be recovered, 
 which is then melted in a crucible. If it is found that there 
 is a nickel plate under the silver, which will resist the strip¬ 
 ping process, the grinding wheel must be resorted to for its 
 removal. 
 
 If on examination the goods appear to be pitted, which 
 might not show before stripping, they are “cut down” on a 
 wood wheel coated with glue and carborundum or No. ioo 
 emery, followed by a leather-covered wheel and No. 150 
 
72 
 
 SILVERPLATING 
 
 emery or finer carborundum, and finished with felt and flour 
 emery. The use of emery paste is discouraged, as it gets a 
 film of mineral grease on or into the goods that is very 
 hard to remove. 
 
 The knives are now dropped in a solution of 8 oz. of sal- 
 soda in i gal. of water, to prevent them from rusting. After 
 dipping for a few minutes in the hot lye (if scoured with 
 paste, gasoline is necessary) the articles are dipped in cold 
 water and scoured with pumice and a stiff bristle brush. 
 Use dilute sal-soda with the pumice to keep the steel from 
 rusting. This is much better and safer than the poisonous 
 cyanide. All stains and rust spots must be carefully scoured 
 out, emery flour being used if necessary. After thorough 
 scouring, rinse in cold water, and put through the potash 
 solution to remove grease. The knives should not be left 
 out in the air, or they will rust, but if the plating tank is 
 not ready they should be placed in the. sal-soda solution. 
 Do not touch with the hands. After plunging them in the 
 lye, the knives are rinsed in cold water and passed quickly 
 through a dip composed of i pt. of muriatic acid to I gal. 
 of water, at a temperature of about 70° F. The goods 
 should now be free from all grease and oxidation, or, in 
 other words, chemically clean. This can be readily deter¬ 
 mined by the way water acts on the surface; if it wets 
 evenly it is clean, but if it shows any repulsion or “duck’s 
 back” it must go into the potash again. 
 
 The knives are now placed in the tank with silver anodes 
 on both sides to secure an even deposit. The anode surface 
 should exceed that of the goods. Use a weak current, not 
 over 1 volt, and move the goods in the bath often while the 
 plating is going on. To secure what is called a “12-dwt. 
 deposit,” or 12 pennyweights of silver to the dozen knives, 
 they should remain in the bath from i )/ 2 to 2 hours. When 
 the operation has been completed, the knives are taken out, 
 scratchbrushed and buffed with a soft rag wheel and silver 
 rouge, care being taken not to use too much rouge. Bur- 
 
SILVERPLATING 
 
 73 
 
 wishing gives an extra finish, but it takes too much time for 
 ordinary jobs. 
 
 ANOTHER SILVER SOLUTION 
 
 Dissolve i oz. of nitrate of silver (always use the high¬ 
 est grade of chemicals) in i pt. of distilled water, or larger 
 amounts in the same proportion. In a separate vessel, dis¬ 
 solve i oz. of potassium cyanide, 99 per cent pure, in ^ pt. 
 of distilled water. Add the cyanide gradually and slowly 
 to the nitrate, stirring carefully with a hardwood stick or 
 a glass rod. Adding the cyanide too rapidly prevents a 
 complete union with the silver, some of which is lost. It is 
 better to pour in a spoonful or two of the cyanide at a time 
 and stir as long as a precipitate is formed, then add more 
 cyanide and stir, and so on. If the precipitate has settled 
 down in a mass, or curd, leaving the liquid clear, the chem¬ 
 ical action has been complete and the precipitate, cyanide of 
 silver, contains all the silver that was contained in the 
 nitrate. If the liquid has a brown tint it shows an excess of 
 cyanide, which is corrected by adding a few drops of silver 
 nitrate until the liquid clears. When the cyanide curd has 
 settled, pour off the liquid, which, if at all cloudy, may be 
 saved in a crock for the recovery of the silver. Wash the 
 curd with clean water several times and dissolve it in a so¬ 
 lution of potassium cyanide, using about one-fifth more 
 than actually required to take up the precipitate. Add dis¬ 
 tilled water in the proportion of 1 gal. to from 1 to 5 oz. of 
 silver, as required. Filter through muslin. This is the 
 cyanide solution of silver used in the plating bath. Work 
 at a temperature of about 6o° F. Do not expose the solu¬ 
 tion to strong sunlight. 
 
CHAPTER VIII 
 
 GOLDPLATING 
 
 I T WILL NOT be necessary here to describe the process 
 of goldplating any further than relates to the work of a 
 small shop or jeweler. Of course the large outfits are en¬ 
 tirely unsuitable for this work. Rings and other articles 
 of jewelry, watch cases and the like, may be plated with a 
 plant that occupies no more space than a kitchen table. 
 Such an outfit is illustrated in Lig. 52. The electroplating 
 supply houses offer an outfit about as follows: One 
 enameled iron vessel; 1 large Bunsen cell; 1 gal. of 24 or 
 14-karat gold solution; gold anode; connecting wire; 
 
 Fig. 52. Small Goldplating Outfit 
 
 scratchbrush; hard and soft gold rouge. Polishing mops 
 one can make for himself. As this sort of work is often 
 done in a dwelling or ill-ventilated room, it is desirable to 
 use a battery which does not give' off noxious fumes. 
 
 Lor goldplating, the goods must be thoroughly cleaned 
 and prepared very much as in the processes for other 
 metals. It is advisable to copperplate articles of soft metal, 
 
 74 
 
GOLDPLATING 
 
 75 
 
 as in silverplating, but quickening with mercury is unnec¬ 
 essary. Copper, silver, brass and various alloys used in 
 making cheap jewelry usually take a gold deposit with no 
 difficulty. Aluminum articles should be coppered in a solu¬ 
 tion of copper sulphate. The better the polish that is given 
 the goods before gilding, the better the work will result. 
 If a matt or frosted surface is desired, roughen the surface 
 with acid or a frosting brush before gilding. Some jewel¬ 
 ers and platers make their own gold solution by dissolving 
 pure gold in a heated solution of potassium cyanide, and 
 passing an electric current through the solution until suffi¬ 
 cient metal is dissolved. The process will not be given here 
 in detail, as in practice it would be found wasteful by any 
 but an expert. Solutions of known strength may be bought 
 of the supply houses at very little above the value of the 
 gold and these save time and labor and are always reliable. 
 As in plating silver, it is not desirable to put several articles 
 of different metals or alloys in the plating bath at once. 
 Several copper articles, or several silver articles, may be 
 worked at the same time. 
 
 In a small earthen dish or crock 6 or 8 in. in diameter, 
 for the plating bath, the articles are suspended by fine cop¬ 
 per wire from a cathode rod of copper the size of ordinary 
 fence wire. See that the connections to the articles are 
 good, and that anything of the link or chain character is 
 attached to the wire in several places. The anode should be 
 of pure gold plate not less than 0.06 inch in thickness. Leaf, 
 or any ribbon thinner than this, is apt to be worn away and 
 wasted. A platinum wire should be used for the anode. 
 As in silver, the anode surface should be slightly in excess 
 of the surface of the cathode. It should be frequently 
 moved in the bath, and always taken out and dried when 
 not in use. 
 
 An excess of current, too large an anode surface, or a 
 deficiency of free cyanide in the solution, is indicated by a 
 gathering of slime on the anode. If the plater knows that 
 
GOLDPLATING 
 
 • 76 
 
 the solution is not overworked or exhausted, he should look 
 carefully to the current and the relation of anode and 
 cathode. 
 
 The temperature of the gilding bath should be from 140° 
 to 180 0 F. when working. At a lower temperature the 'de¬ 
 posit is lighter colored, and below i'20° it will be of a 
 straw color or brassy tint. As the internal resistance of the 
 bath is reduced by heat, the color darkens, and above 160° 
 it takes on a coppery hue. A fresh solution deposits gold 
 of a very light tint, while as it grows older, the tint grows 
 darker. The alloys are acted upon by the solution, as are 
 the copper wires, and they gradually impart an alloy to the 
 coat deposited. 
 
 For small work, a single cell, working at ^ volt and a 
 fraction of an ampere, will give sufficient current. As in 
 silverplating, when the current is too strong, the work 
 “burns” and the gold is deposited in a loose, powdery 
 form, reddish brown in color. It is best to have a rheostat, 
 in gilding, even with a small outfit, to insure proper volt¬ 
 age, for this is one of the places where guesswork does not 
 pay. If a job is “burned” so as to give it a bronze tinge, it 
 can only be made right by stripping and regilding. Some¬ 
 times, however, a dark brown deposit of gold is caused by 
 excess of free cyanide and a deficiency of gold in the solu¬ 
 tion, a condition which is remedied by adding cyanide of 
 gold to the solution. 
 
 Another condition affecting the color of the gilding is the 
 metal which forms the base, which may be said to shine 
 through the extremely thin film of gold and impart its own 
 hue to the gilding; hence, if other conditions are right, the 
 gilding, which may look at first very dark on copper, or 
 light on silver, will be apt to improve as more gold is de¬ 
 posited. A knowledge of the behavior of gold in depositing 
 on other metals will permit the expert plater to produce 
 some very attractive effects. Thus, on freshly deposited 
 copper and silver, on frosted surfaces, and where frosted 
 
GOLDPLATING 
 
 77 
 
 and burnished effects are combined, a thin gilding often 
 produces beautiful results, which may be given fanciful 
 names such as gold of Ophir, Ormus gold, Alaska gold, 
 etc. There are several popular fallacies in connection with 
 the color of gold from various localities and as regards 
 certain so-called “golds.” Thus, it is commonly believed 
 that African gold is of a coppery hue, while California gold 
 is light in tint; that “rolled gold” is anything but gilt, and 
 usually a very low grade of gilt at that. But these are 
 simply fallacies, though so dear are they to the popular 
 heart that it is useless to attempt to destroy them. 
 
 If the plater has progressed far enough to handle several 
 plating vessels with different solutions, he may work with 
 various alloys, or copper, silver, etc., which will give almost 
 as many hues to the goods (only portions of which may be 
 immersed in the bath) as could be given by using pigments 
 applied with a brush. For example, a green gilt is pro¬ 
 duced by adding a silver cyanide solution, or the use of a 
 copper anode until the desired tint is obtained. Rose pink 
 is effected by scratchbrushing the first filmy deposit of 
 gold, then giving it a thin coating of copper, and finishing 
 with a blush of gold on the face of the copper. These, 
 however, may be called eccentricities for the amusement 
 and diversion of a wealthy alchemist, rather than the work 
 of a commercial electroplater. 
 
 Heavy gilding is done, not by allowing the article to re¬ 
 main long in the bath, but by taking it out often and 
 scratchbrushing it to remove the loosely adhering particles 
 of gold and then returning it to the bath for another coat. 
 
 Small articles of steel, if they have a highly polished sur¬ 
 face, may be thoroughly cleansed and put through the gild¬ 
 ing bath suspended in a platinum basket, as described for 
 buttons, etc., in silverplating. When this process is fol¬ 
 lowed, the gold on the platinum basket may be recovered 
 by hanging it on the anode rod in the bath. 
 
 A metal egg cup or salt cellar or other cup-shaped vessel 
 
78 
 
 GOLDPLATING 
 
 may be gilded on the inside by filling it with the solution 
 and connecting it with the cathode rod, while a small plate 
 of gold forming the anode, is suspended in the solution. 
 
 Gold is deposited more rapidly than nickel or copper but 
 not as rapidly as silver, the ratio being 37.8 gr. per hour 
 with a current of one ampere. When it is calculated that 
 sufficient gold has been deposited, which, after all, can only 
 be judged by experience, the articles are taken out, rinsed 
 in clear water, scratchbrushed, dried by rubbing in hot box¬ 
 wood sawdust, and weighed. Goldsmiths’ balances showing 
 tenths of grains, will be required and should be kept in a 
 separate closet assigned to the goldplating outfit. The 
 articles having been carefully weighed before plating and 
 after the process is completed, the difference shows the 
 amount of metal deposited. 
 
 In actual practice the work will be something like this: 
 A charge of say $1.00 is made for gilding or triple-plating 
 a watch fob, badge or some similar article. (The term 
 “triple plate” is like rolled gold, it does not mean much of 
 anything, but it sounds well and people like it). This will 
 allow for 5 gr. of gold, and $.79 for work, there being 23.22 
 gr. of pure gold in one dollar. A piece of gold plate having 
 a larger surface than the fob or badge, supposing it to be 
 the only article to be gilded, is suspended on the anode rod 
 and the fob, prepared and weighed as already described, is 
 wired on the cathode rod. If several pieces are gilded at 
 the same time, of course the expense of the process in time 
 is proportionately reduced. After remaining in the bath 
 10 minutes, the fob is taken out, scratchbrushed and 
 weighed. If it is found to have gained, say, 2 gr. in the 10 
 minutes time, it is clear that in 15 minutes more it should 
 take on the required additional 3 gr., and it is put back 
 for that time. 
 
 In gilding bracelets, chains or other similar articles of 
 jewelry, care should be taken to see that all joints are well 
 soldered, so that they do not become filled with the plating 
 
GOLDPLATING 
 
 79 
 
 solution and cause errors in the calculation of the gold 
 deposit as indicated by the weight. 
 
 Jewels in rings, society emblems, etc., should be re¬ 
 moved before gilding and placed in a small box properly 
 marked and kept under lock and key. They may be glass 
 but that, of course, is a professional secret. All soft metal 
 
 Fig. 53. Lathe Buff for Goldplating 
 
 and alloy goods and articles which have been repaired 
 should be copperplated before gilding. 
 
 Waste from the gold table should be saved for the re¬ 
 covery of the gold it contains. This is done by letting the 
 water settle and carefully dipping off the clear water. 
 Evaporate the rest (if a solution, all should be evaporated) 
 in a smooth porcelain-lined kettle or dish. To the remain¬ 
 ing salt: or residuum add an equal bulk of litharge (lead 
 monoxide) and mix well. Calcine in a crucible and keep 
 
80 
 
 GOLDPLATING 
 
 at a glowing heat over a gas burner until all the litharge has 
 been decomposed, leaving a button of lead and gold with 
 the silver, copper and other metals of the alloy. This may 
 be sent to the assayer, who will allow for the precious 
 
 Fig. 54. Lathe Buff for Goldplating 
 
 metals it contains. Unless the plater is an expert chemist, 
 however, he had better not undertake the delicate process 
 of reduction. 
 
 The tools and articles used in goldplating should be kept 
 for that purpose only, and not mixed up with others. The 
 brushing and cleaning may be done entirely by hand, but if 
 much work of this character is done a small lathe will be 
 found useful. A small scratchbrush of fine brass wire, 
 
 Fig. 56. Hand Buff 
 
 Fig. 55. Hand Buff 
 
 one of crimped wire, several small brushes, mops of swans- 
 down muslin, soft felt, chamois skin, etc., for the lathe and 
 hand work, with a supply of French rouge compound, are 
 among the necessaries. Several kinds of buffs are shown in 
 
GOLDPLATING 
 
 81 
 
 Fi g s - 5 3 > 54 , 55 and 56. Small brushes or mops on pencils 
 and penholders which will answer all the purposes of more 
 expensive articles, may be made up by the gilder. Burnish¬ 
 ers are made of steel and agate, and economical jewelers 
 in the country are said to use their wives’ manicure sets 
 for this purpose. All repairs, filling of pin holes, removal 
 of dirt, etc., must be done before gilding. 
 
 Gilded work should have only sufficient scratchbrushing 
 to take off the loose metal. The operator should also ham¬ 
 mer down the minute particles into a smooth, even coat. 
 After this is done, scour with soft felt, swansdown muslin 
 and chamois, using a little fine rouge composition. In 
 using rouge, one must take care to wash it all out of articles 
 that have engraved work or crevices which are not easily 
 reached with the brushes. Chains, rings, thimbles, etc., are 
 best polished by using small bobs of fine felt or chamois on 
 the polishing lathe. 
 
 In the process of brushing, a lubricant should be used 
 both to prevent the gold wearing away and to keep the 
 brass from depositing on the gold. English platers always 
 recommend stale beer, but a weak solution of linseed is 
 really better. 
 
 If a lathe is used, the brush should be protected by a 
 hood to prevent the waste of gold in splashing. A few 
 minutes may be profitably spent in watching an expert 
 polisher at work. Notice the brushes and bobs used for 
 each class of work, and how the article is held against the 
 brush so as to get the smooth brushing motion and not the 
 direct blow of the bristles, and how spattering is avoided 
 as much as possible simply by the position in which the 
 article is held. 
 
 BURNISHING GOLD 
 
 Burnishing is an art in itself. Much harm can be done 
 by using a rusty steel burnisher, or one with a sharp edge. 
 Rust is corrosion of the metal by tbe oxygen in the air, or 
 from acids, and the result is a roughening of the bright 
 
82 
 
 GOLDPLATING 
 
 surface. Steel burnishers should have all the care one 
 gives to a good razor and perhaps more, for a rough bur¬ 
 nisher may spoil a job. The common shapes of steel bur¬ 
 nishers are show in Fig. 57. Steel burnishers should have 
 their bright surfaces kept in good condition by frequent 
 rubbings on a soft leather pad with putty powder. The 
 
 Fig. 57. Steel Burnishers for Goldplating 
 
 burnishers should never be put away without being wiped 
 with an oiled cloth, in which they should be wrapped to 
 protect them from acid fumes and moisture. Burnishers 
 of agate or bloodstone cost more than those of steel, but 
 they do not rust. They also have a smoother and harder 
 surface than the best steel, and so give a brighter polish to 
 the goods. Especial care must be given to agate burnish- 
 
GOLDPLATING 
 
 83 
 
 ers to see that the corners do not get chipped, which gives 
 them a cutting edge that is destructive to the articles on 
 which they are worked. They should always be wrapped 
 in muslin or linen when put away, and carefully examined 
 under a glass before used. These tools cost from $1.00 to 
 $1.25 for steel and $1.50 to $2.50 for agate, etc. Lend your 
 plating dish, if you must, for a preserving kettle, and let 
 thieves run off with your gold solution, but never, under 
 any circumstances, lend your burnishers. 
 
 The following directions will help the beginner: Regard 
 the article on which you are working as a soft material, as 
 indeed it is, covered by a very thin film of an even softer 
 material. The burnishing tool simply presses down these 
 particles, mats them together and so smooths and brightens 
 the surface, much as a boy makes a hard snowball out of 
 flaky snow, or the glazier spreads and packs putty against 
 the edge of a sheet of glass. Remember that the object 
 from the beginning of the polishing is not to wear away the 
 gold, but to smooth it down. With this purpose in view the 
 ring or other article is held on a soft pad with one hand, 
 while with the other the burnisher is pressed hard on the 
 surface with swathing strokes overlapping each other and 
 always in the same direction. To avoid friction, the sur¬ 
 face may be lubricated with weak castile-soap suds freshly 
 made, using the steel burnisher first and finishing with 
 agate. When a sufficiently bright and uniform surface is 
 obtained, rinse in hot water and dry with a clean soft linen 
 cloth. 
 
 For polishing steel and agate burnishers, a fine Lake 
 Superior stone is used (one of clear flint, which should be 
 kept exclusively for this purpose, and is to be used only for 
 removing rust or sharp edges), and a buff, which is like a 
 hone made of soft leather. To make this, get a piece of soft 
 dressed leather (calf skin will do, but deer skin is better; 
 chamois is too thin), say, 2 by 4 in. Boil it in soft water to 
 remove chemicals, dry it quickly and soften by rubbing. 
 
84 
 
 GOLDPLATING 
 
 Then glue it to a block of beech or maple i in. thick, 5 in. 
 long by 3 in. broad. The dimensions are not important, but 
 are given as a general guide. Use warm glue, but thin 
 enough to strike through the leather, and press down with 
 a clean block and weights. Keep it covered. If - the buff 
 and stone are permitted to gather dust they become abra¬ 
 sives rather than polishers, in fact, grindstones. Therefore 
 they should be kept in boxes or wrapped in a bit of muslin. 
 The value of tools depends very much on the way they are 
 kept. 
 
 Burnishing requires a good light, a careful eye and a 
 steady hand. It takes skill, which is a little word that in¬ 
 cludes everything. As to the brushing, there are many 
 details of the work that cannot be given in the printed 
 directions and which can only be learned by careful prac¬ 
 tice and the observation of the work of an expert. 
 
 Burnishing should be done in a room that is free from 
 dust. The windows should be protected by gauze screens. 
 Do not try to burnish by artificial light, and it is better to 
 have no gas or stove in the room, or furnace heat, as these 
 all give out gases injurious to fine polished surfaces, 
 especially silver, 
 
CHAPTER IX 
 
 MISCELLANEOUS 
 
 T HE NICKELING of molded work is a more delicate 
 process than the plating of metal goods, but not differ¬ 
 ent after the process has been learned. A wax mold of 
 the article having been prepared, it is dusted with black 
 lead and placed in the copper bath for a thin film of cop¬ 
 per. The mold must be free from undercutting, or inter¬ 
 stices which would prevent a free separation of the mold 
 and the matrix. The copper matrix is then removed from 
 the mold and placed in the nickel vat and a coat of nickel 
 of the desired thickness applied. 
 
 TO MAKE COPIES OF WAX MOLDS 
 
 Fine copies of wax impressions can be made in a very- 
 simple manner as follows: If the article is no laiget than 
 an ordinary medal or brooch intaglio, take an ordinary 
 tumbler and partially fill it with a strong solution of sul¬ 
 phate of copper. Then make a porous cell by rolling a piece 
 of stiff brown paper around a piece of broom handle and 
 fasten the edge with sealing wax, putting in a bottom in 
 the same way. A Welsbach burner box will serve very 
 well. Make a solution of i part of oil of vitriol and 5 
 parts of water (adding the vitriol slowly to the water), 
 and pour this mixture into the porous cell. Wind the end 
 of a small copper wire around the end of a bit of zinc the 
 size of a pencil and drop the zinc into the porous cell. 
 Attach the other end of the wire to the wax impression, 
 which is prepared thus: Pour melted beeswax on the 
 medal, and remove carefully when cold. Then dust the 
 mold with black lead and polish with a stiff camel’s-hair 
 brush. Suspend the porous cup and the wax mold in the 
 tumbler, connect with a batteiy (one cell) and run about 
 
 85 
 
86 
 
 MISCELLANEOUS 
 
 12 hours. Take out and polish, and a good copy should 
 result. 
 
 OXIDIZING COPPER, BRONZE AND SILVER 
 
 The process of oxidizing is simply the corroding or rust¬ 
 ing of the bright metal surface to give it a frosted appear¬ 
 ance. It may be done in various ways to give the effect 
 desired. A simple method is as follows: Dissolve y 2 oz. 
 of sulphuret of potash in i gal. of water, and use as a dip 
 solution at 130° F. in a vitrified earthenware crock. The 
 high light is then brought out by slightly touching the work 
 to a felt wheel charged with rouge. Sewed buffs are also 
 used with good effect, and for a rougher finish the steel or 
 brass wire brush is used. 
 
 BRONZING 
 
 Dissolve 8 oz. of C. P. cyanide of potash in 1 gal. of 
 water using a glazed jar or crock, then dissolve in this 4 
 oz. of carbonate of soda. Mix y / 2 oz. of carbonate of cop¬ 
 per (dry) and y oz. of carbonate of zinc (dry) into some 
 water, held in reserve, until they form a thin paste, then stir 
 this paste into the bulk of the solution. Dissolve 4 oz. of 
 bisulphate of soda in a small quantity of water and add 
 this to the solution. Add y 2 gal. of aqua ammonia to each 
 50 gal. of solution. Use cast bronze anodes in the tank. 
 
 BRONZE COPPERING SOLUTION 
 Dissolve 2 oz. of copper carbonate in 1 gal. of cold dis¬ 
 tilled water, and add it to y 2 gal. of water in which has been 
 dissolved 4 oz. of potassium carbonate; add enough liquid 
 ammonia to dissolve the copper carbonate and stir until 
 the copper carbonate is entirely dissolved. Make a solu¬ 
 tion of potassium cyanide in y 2 gal. of distilled water, us¬ 
 ing enough cyanide (approximately 3^ oz.) to destroy the 
 blue color of the copper carbonate solution; mix with the 
 above and^ filter through felt or double muslin. Work at 
 8o° to ioo° F. To deepen the bronze tint dip the coppered 
 goods in a solution of sal ammoniac. 
 
MISCELLANEOUS 
 
 87 
 
 SILVERPLATING WITHOUT A BATTERY 
 
 A simple and practical home silvering process, which 
 will work on copper or brass or any alloy of copper, is as 
 follows: Dissolve a silver quarter or its equivalent in just 
 enough nitric acid and add slowly i or 2 oz. of common 
 salt dissolved in just enough water to take up the salt. De¬ 
 cant the liquid and wash the silver-chloride precipitate with 
 water. Dissolve it in a solution of potassium cyanide. Filter 
 the solution and make up with distilled water. Clean the 
 articles to be plated with lye and hang them in a crock and 
 boil a few seconds in this solution. Be careful not to 
 breath the fumes of this solution, which is a deadly poison. 
 
 CLEANING BRASS AND STEEL 
 
 For exhibition purposes, but not for plating, brass and 
 steel articles may be quickly and cheaply cleaned by rub¬ 
 bing with vinegar and salt, or dilute oxalic acid. Wash 
 immediately and polish with tripoli and sweet oil. 
 
 TO PREVENT TARNISH ON SILVER 
 
 Silver may be kept from tarnishing by applying a thin 
 coat of pyroxylin lacquer. 
 
 LACQUERING 
 
 Many plated articles, such as buckles, trimmings, etc., 
 for the trade, are lacquered to protect the plating and give 
 a higher and more lustrous finish. The lacquer should be 
 thin, colorless and of good quality. It should be applied 
 carefully to insure a good job. Lacquers are of two kinds, 
 dip lacquer and brush lacquer, and the names will indicate 
 their use. 
 
 The dip lacquer should be kept in a glass or stoneware 
 tank or jar, with a tight cover. If much work is done a 
 tin-lined wooden tank is used. The goods should be 
 cleaned as for plating. Hang them on a wire so that they 
 
88 
 
 MISCELLANEOUS 
 
 Fig. 60. General View of Lacquer Room 
 
MISCELLANEOUS 
 
 89 
 
90 
 
 MISCELLANEOUS 
 
 do not touch each other, dip and let them drip over the 
 tank. The method is shown in Fig. 58. The lacquer should 
 run well, and not be thin enough to be iridescent (rainbow- 
 colored) nor thick enough to show the drip—that is, the 
 accumulated hardened drops at the bottom. Work at about 
 ioo°F. Dry in air free from dust at ioo° F. to 140° F. 
 If the lacquer has to be thinned, use a thinner of the same 
 grade. 
 
 Brush lacquers are used thicker than dip lacquers, but 
 as this is possible without showing iridescence, give a flow¬ 
 ing coat with a soft lacquer brush as illustrated in Fig. 59. 
 See that no rouge, or any composition of any sort or any 
 
 greasy deposit is left on the goods, as this will give a milky 
 appearance. Do not touch the articles with the hands. 
 
 A general view of the lacquer room is shown in Fig. 60. 
 
 Manufacturers of metal goods are now successfully 
 applying lacquer by the use of sprayers operated by com¬ 
 pressed air. A hand sprayer, Fig. 61, is also made which 
 answers very well where compressed air is not available. 
 The great advantages of the sprayer where much lacquer¬ 
 ing is done lies in the fact that a much smaller quantity 
 
 
MISCELLANEOUS 
 
 91 
 
 and a thinner body of lacquer is required than by the dip 
 or brush methods. 
 
 REMOVAL OF STAINS 
 
 To remove stains of copper sulphate, or salts of mer- 
 cur y, gold, silver, etc., from the hands, wash them with a 
 very dilute solution of ammonia, and then with plenty of 
 water; if the stains are old ones, they should be rubbed 
 with the strongest acetic acid, and then treated as above. 
 
 Grease, oil, tar, etc., may be removed from the hands or 
 clothes by rubbing with a rag saturated with benzine, 
 turpentine, or carbon bisulphide. 
 
CHAPTER X 
 
 FIRST AID TO THE INJURED 
 
 T HE CHEMICALS with which the electroplater has to 
 do, are, many of them, deadly poisons, and their com¬ 
 binations often produce corrosive and poisonous gases. 
 Familiarity breeds contempt, as we know, but it is criminal 
 carelessness, and nothing less, if the plater allows his famil¬ 
 iar use of deadly poisons to endanger the lives of himself 
 and his workers. 
 
 Have the following list of antidotes and the directions 
 for their use typewritten and tacked up on the door of a 
 “First Aid” cabinet on the wall. Study it and memorize the 
 leading points, because when an accident happens with the 
 hydrochloric acid, the sulphuric acid or the like, there is no 
 time for study, and if the right thing is not done on the 
 instant, it is a case for the coroner. 
 
 ANTIDOTES FOR POISONS 
 
 In case of poisoning, send or telephone for a doctor, and 
 take remedial measures as quickly as possible, as follows: 
 
 Nitric, Hydrochloric or Sulphuric Acids. —Give as much 
 tepid water as possible to act as an emetic, or milk, the 
 whites of eggs, some calcined magnesia, or a mixture of 
 chalk and water. If those acids, in a concentrated state, 
 have been spilled on the skin, apply a mixture of whiting 
 and olive oil. If the quantity is very small, simple washing 
 with plenty of cold water will suffice. A useful mixture, 
 in cases of burning with strong sulphuric acid, is formed 
 with i oz. of quicklime slaked with ^ oz - °f water, and 
 then adding it to i qt. of water. After allowing to stand 
 some time, pour off the clear liquid and mix it with olive 
 oil to form a thin paste. 
 
 Potassium Cyanide, Hydrocyanic Acid, etc. —If cya- 
 
 92 
 
FIRST AID 
 
 93 
 
 nides, such as a drop of an ordinary plating solution has 
 been accidentally swallowed, water, as cold as possible, 
 should be run on the head and spine of the sufferer, and a 
 dilute solution of iron acetate, citrate or tartrate given. If 
 hydrocyanic-acid vapors have been inhaled, cold water 
 should be applied as above, and the patient be caused to 
 inhale air containing a little chlorine gas, which can be kept 
 in solution in water in a tightly stoppered bottle. Chlorine 
 solution may be purchased in bottles. Never dip the arms 
 into a plating solution to recover any work that has fallen 
 off the wires, because the skin often absorbs cyanide 
 liquids, causing painful sores. In such a case, wash well 
 with water, and apply the olive oil and lime-water mixture. 
 
 Alkalies .—These bodies are the opposite of acids in 
 character, so that acids may be used as antidotes. It is 
 preferable to employ weak acids, such as vinegar or lemon¬ 
 ade; but if these are not at hand, then use exceedingly 
 dilute sulphuric acid, or even nitric acid diluted, so that it 
 just possesses a decidedly sour taste. After about ten 
 minutes take a few teaspoonfuls of olive oil. 
 
 Mercury Salts .—The white of an egg is the best antidote 
 in this case. Sulphur and sulphureted hydrogen are also 
 serviceable for the purpose. 
 
 Copper Salts .—The stomach should be quickly emptied 
 by means of an emetic, or in want of this, the patient 
 should thrust his finger in the back of his throat, so as to 
 induce vomiting. After vomiting, drink milk, white of an 
 egg, or gum water. 
 
 Lead Salts .—Proceed as in case of copper salts. Lemon¬ 
 ade, soda water and sodium carbonate are also serviceable. 
 
 Acid Vapors .—Admit immediately an abundancq of 
 fresh air, and inhale the vapor of ammonia, or a few drops 
 of ammonia may be put into a glass of water and the solu¬ 
 tion drunk. Take plenty of hot drinks and excite warmth 
 by friction. Employ hot foot baths to remove the blood 
 from the lungs. Keep the throat moist by sipping milk. 
 
94 
 
 FIRST AID 
 
FIRST AID 
 
 95 
 
 FIRST-AID CABINET 
 
 In a handy little closet on the wall (you can make one 
 out of a soap box) as shown in Fig. 62, keep the supplies 
 listed below, omitting none of them because you may pos¬ 
 sibly have them somewhere about the shop. The whole 
 outfit will not cost $2.00 and it may save a life. 
 
 8-oz. bottle of olive oil. Label—For acids and alkalies. 
 
 4-oz. bottle of calcined magnesia. Label—For acids. 
 
 4-oz. bottle of lime and oil dressing. Label—For burns. 
 —Shake well. 
 
 4-oz. bottle of ammonia. Label—For acid vapors. 
 
 F2 oz. cream of tartar. Label—For mercury salts. 
 
 % lb. vaseline. Label—For burns. 
 
 )/2 lb. absorbent cotton. 
 
 4 oz. iron acetate. Label—For cyanides. 
 
CHAPTER XI 
 
 BUSINESS SUGGESTIONS 
 
 \X 7 HEN THE beginner has finished several samples of 
 ^ * work, which will pass the inspection of a good 
 judge, he is then ready to set up in business. A good 
 scheme is to start out with some simple article experience 
 has shown can be done easily and well, such as a collar 
 button, a belt buckle, watch fob or perhaps a souvenir 
 spoon if a good original design can be made. Put a fair 
 price on the article and show it to all your friends. Adver¬ 
 tise it in the local paper and give the editor one or more 
 for his own use. Get some cards neatly printed with just 
 your name, business and location and distribute them. Do 
 not load down your card or billhead with a lot of useless 
 printing. Work the automobile garages and try to get their 
 business. Remember, you must make your business known 
 or people will not come to you. Don’t hide your card 
 under a bush. 
 
 Watch your own work carefully, and that of your assist¬ 
 ant, if you have one, still more carefully. Get a young fel¬ 
 low of sense and ambition and pay him by the week. Piece 
 work is apt to be slighted and does not pay. 
 
 Keep careful accounts, and especially a book of receipts 
 and description of goods. This prevents annoying errors. 
 Have an understanding with a larger shop that does good 
 work to take jobs off your hands that you are unable to 
 undertake, and then you need not turn a job away because 
 you have not the facilities for taking care of it. By 
 watching how the bigger shop conducts its business you 
 will get points for managing your own. If you make an 
 estimate on a job that brings you a loss, you may tell your 
 customer, but do not attempt to raise the price. It will 
 please him to know that he gets more than he pays for, 
 and you can charge the difference up to experience. 
 
 96 
 
Alphabetical Index 
 
 Acidity, testing for, 62. 
 
 Acids, antidotes for, 92. 
 
 Acid vapors, antidotes for, 93. 
 Alaska gold, 77. 
 
 Alkalies, antidotes for, 93. 
 Ammeter, 28. 
 
 Ampere, definition of, 16. 
 
 Anode, 12. 
 
 Antidotes for poisons, 92, 93, 95. 
 Apparatus, simple forms of elec¬ 
 troplating, 10. 
 
 Arrangement of tanks and bat¬ 
 tery, 33. 
 
 Batteries, electric, 13- 
 Battery, How a, Works, 20. 
 Blister, removing, 63. 
 
 Blisters, 70. 
 
 Bobs, 48. 
 
 Bronze coppering solution, 86. 
 Bronzing, 86. 
 
 Brush, cup-shaped, 43 
 Brushes, various, 43, 44, 45. 46. 
 Brush lacquer, 90. 
 
 Brush lacquering, 89, 91. 
 Buffing, correct way of holding 
 article, 49. 
 
 Buffing lathe, power, 37. 
 
 Buffs. 48. 
 
 Bull-neck leather wheel, 47. 
 Bunsen cell, 18. 
 
 Bunsen cell, best uses of, 19. 
 “Burned” work, 76. 
 
 Burnishers for gold-plated ware, 
 81, 82. 
 
 Burnishing directions, in gold- 
 plating, 83, 84. 
 
 Burnishing gold. 81. 
 
 Business suggestions, 96. 
 
 Canvas wheel, 46. 
 
 Carborundum, 49. 
 
 Carborundum wheel, 47. 
 Cathode, 12. 
 
 Cleaning before electroplating, 
 14- 
 
 Cleaning brass and steel, 87. 
 Cleaning goods before plating, 
 53- 
 
 Cleansing solutions, 53. 
 Compound-wound dynamo, 26. 
 Compressed-leather wheel, 48. 
 Connections for electroplating. 
 11. 
 
 Connections of tanks, dynamos 
 and rheostats, 34. 
 
 Coppering solution, 56. 
 Copperplating, 56. 
 
 Copper salts, antidotes for, 93. 
 Corundum wheel, 47. 
 
 Covers for tanks, 31. 
 
 Crocus, 50. 
 
 Cutting down, 71, 73. 
 
 Cyanide, antidote for, 92. 
 Daniell cell, 17. 
 
 Difference of potential, 16. 
 
 Dip lacquer, 90. 
 
 Dip lacquering, 89, 90. 
 
 Dipping baskets, 39. 
 
 Dynamo, 25. 
 
 Electrical equipment, 15. 
 
 Electric batteries, 15. 
 
 Electric circuit, II. 
 
 Electrolysis, 13. 
 
 Electromotive force, 16. 
 Electroplating, definition, 9. 
 Electroplating outfit, simple, 12 
 J 3- 
 
 Electroplating rule, 69. 
 
 97 
 
ALPHABETICAL INDEX 
 
 98 
 
 Electroplating tank, home-made, 
 30. 
 
 Emery, 49. 
 
 Emery wheel, 47. 
 
 E. m. f., 20. 
 
 English Bunsen cell, 18. 
 Equipment, miscellaneous, 37. 
 Filling plating barrel, 52 . 
 
 First aid cabinet, 94, 95. 
 hirst aid to the injured, 92. 
 blow of current, analogy, 20. 
 French Bunsen cell, 19. 
 
 Gilding, crock or glazed dish for, 
 32 . 
 
 Gilding jewelry, 78. 
 
 Goldplating, 74. 
 
 Goldplating, crock or glazed dish 
 for, 32. 
 
 Goldplating outfit, 74. 
 
 Grouping of cells, 21, 22, 23, 34. 
 Hand brushes, 45, 46, 48. 
 
 Hand sprayer, 90. 
 
 How metal is deposited, 10. 
 Hydrochloric acid, antidote for 
 92. 
 
 Flydrocyanic acid, antidote for, 
 92. 
 
 Flydrometer, 37, 38. 
 
 Jewelry, gilding, 78. 
 
 Joining for quantity, 21. 
 Lacquering, 87. 
 
 Lacquer, removing, 54. 
 
 Lacquer room, 88. 
 
 Lathe brush for inside of gob¬ 
 lets, 43. 
 
 Lathe buffs for goldplating, 79, 
 80. 
 
 Lead salts, antidotes for. 93. 
 Litmus paper, 50. 
 
 Loose-wire brush, 45, 48. 
 Measuring instruments, 27. 
 Mechanical plating tank, 51. 
 Mercury salts, antidotes for, 93. 
 Methods, old and new, 10. 
 Miscellaneous equipment, 37. 
 
 Molded work, nickeling, 85. 
 Muslin and cotton wheel, 46. 
 Negative metal, 15. 
 
 Negative pole, 11. 
 
 Nickel anodes, forms of, 59, 6o, 
 61. 
 
 Nickeling molded work, 85. 
 Nickelometer, 62 . 
 
 Nickelplating, 58. 
 
 Nickel, rate of deposition of, 62. 
 Nickel-stripping bath, 59. 
 
 Nitric acid, antidote for, 92. 
 Ohm, definition of, 16. 
 
 Ophir gold, 77. 
 
 Ormus gold, 77. 
 
 Oxidizing, 86. 
 
 Parallel grouping of cells, 21, 22, 
 24. . 
 
 Path of current, 11, 12. 
 
 Plating barrels, 52. 
 
 Plating shop, 40. 
 
 Plating tank, making ready, 32. 
 Plating tank, mechanical, 51. 
 Plating vats, 31. 
 
 Platinum black, 17. 
 
 Poisons, antidotes for, 92, 93, 95. 
 Polarization, 17. 
 
 Polishing, correct way of hold¬ 
 ing article in, 49. 
 
 Polishing machine, 36. 
 
 Polishing tools and powders, 43. 
 Positive element, 16. 
 
 Positive pole, n. 
 
 Potassium cyanide, antidote for, 
 92. 
 
 Potential, difference of, 16. 
 
 Power polishing and buffing 
 lathe, 37. 
 
 Preparing small articles for plat¬ 
 ing, 52 . 
 
 Pressure, electric, 20. 
 
 Pumice, 49. 
 
 Quickening, 65. 
 
 Quickening solution, 65. 
 Re-amalgamating zincs of Dan- 
 iell cell, 18. 
 
ALPHABETICAL INDEX 
 
 99 
 
 Recharging Daniell cell, 18. 
 Regulating instruments, 27. 
 Replating knives, 71. 
 
 Resistance box, 21. 
 
 Resistance, electric, 21. 
 Respirator, home-made, 38, 39. 
 Rheostat, 21, 27. 
 
 Rolled gold, 77. 
 
 Rotten stone, 50. 
 
 Rouge, 50. 
 
 Rust, removing, 53, 54 - 
 Sand-blast finish, 48. 
 
 Satin finishing, 48. 
 
 Scouring troughs, 35. 
 Scratchbrushes, 43, 44- 
 Scrubbing troughs, 35 - 
 Scum, removing, 50. 
 
 Series grou; ng of cells, 21, 22, 
 23 - 
 
 Series-parallel grouping of cells, 
 21, 22, 24. 
 
 Sheffield lime, 50. 
 
 Shop arrangement, general plan 
 of, 42. 
 
 Shop equipment, 30. 
 Shunt-wound dynamo, 26. 
 Silverplating, 65. 
 
 Silverplating outfit, how to make 
 a small, 13. 
 
 Silverplating nail articles, 71. 
 Silverplating without a battery, 
 87 - 
 
 Silver sand, 50. 
 
 Silver solution, 66, 73 - 
 Srnee cell, 16. 
 
 Sprayer, hand, 90. 
 
 Stains, removing, 91. 
 
 Strength of silver solution, 67. 
 Strikes, 72, 73. 
 
 Stripping,. 54. 
 
 Stripping nickelplate, 58. 
 Stripping solution, 54. 
 
 Sulphuric acid, antidote for, 92. 
 Tampico brush, 48. 
 
 Tank, 13, 30. 
 
 Tank regulation, 35. 
 
 Tarnishing, to prevent nickel 
 from, 64. 
 
 Tarnish, removing, 54. 
 
 Tarnish, to prevent, on silver, 
 8 7 - 
 
 Temperature of plating shop, 41. 
 Triple gold plate, 78. 
 
 Tripoli, 50. 
 
 Vats, plating, 31. 
 
 Ventilating the shop, 41. 
 Verdigris, removing, 53. 
 
 Vienna lime, 50. 
 
 Voltage, 20. 
 
 Volt, definition of, 16. 
 
 Voltmeter, 28, 29. 
 
 Walrus wheel, 47, 49 - 
 Wax molds, 85. 
 
 Wheels, various, 46, 47, 48. 
 Whiting, 50. 
 
 a* 
 
By PROF. F. D. CRAWSHAW 
 
 Assistant Dean, College of Engineering 
 University of Illinois 
 
 METAL SPINNING is one of the Popular 
 Mechanics Handbook Series and has 80 pages, 
 33 illustrations, is bound in attractive cloth 
 covers and printed on a fine quality of paper. 
 
 This handbook is unique in that it is- the only book pub¬ 
 lished on this interesting art, instructions regarding which 
 have previously been handed down by word of mouth from 
 generation to generation of expert metal spinners. 
 
 It is “Written so you can understand it” by a man well 
 
 qualified because he has made a thorough study of all obtain¬ 
 
 able information on the subject. He has tried out the different 
 methods himself and herein he sets forth the best practice. 
 
 Concise, yet complete, this book is adapted to use as a 
 text in manual training and industrial schools and will be 
 found a practical working manual both by those who desire 
 to spin metal as an art recreation and those who wish to 
 follow this work as a trade. 
 
 Explicit instructions are accompanied by figures to illus¬ 
 trate the meaning. It tells not only what tools are required, 
 but how to make each kind. Definite forms to be spun are 
 treated, and finally the unclassified and more difficult work is 
 dealt with. 
 
 Contents* Chapter U The Lathe and Its Uses; 2, Tools; 3, The 
 Preparation of Metal for Spinning; 4, How to Spin a 
 Shallow Dish; 5, How to Spin a Deep Dish; 6, How to Spin a Vase; 7, 
 How to Spin Some Unclassified Forms. 
 
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 “WRITTEN SO YOU CAN UNDERSTAND IT” 
 
 By JOHN D. ADAMS 
 
 handbooks. A complete manual for 
 art metal workers giving every detail for 
 making a great variety of useful and orna¬ 
 mental objects such as book ends, desk sets, 
 pad corners, paper knives and letter openers, 
 stationery racks, rocking blotter, desk calen¬ 
 dars, match boxes, tie and pipe racks, whisk 
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 T HIS is the first of a series of handbooks on industrial 
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 MECHANICS. This book consists of a number of 
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 are accompanied by dimensioned working drawings. 
 
 Like POPULAR MECHANICS, it is in plain , simple lan¬ 
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 possessing a slight knowledge of how to use tools can easily 
 make the various pieces described. 
 
 Among the contents are: 
 
 Forty Styles of Chairs, An Easily Made Book-Shelf, How to Make a Porch 
 Chair, A Portable Table, A Pyrographer’s Table, How to Make a Mission 
 Library Table, How to Make a Lamp Stand and Shade, How to Make a 
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 thoroughly and plainly. 
 
 CONTENTS: 
 
 Making Out a Stock Bill—Laying Out Rough Stock—Hand 
 Saws—Sawing with Hand Saws—Planes: How to Set and 
 Adjust the Jrons-Squaring Up Mill Planed Stock—Squar¬ 
 ing Up Rough Stock—Whetting Plane Irons and Chisels— 
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 ing a Magazine Stand—Making a Table—Making a Cabinet. 
 
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MR. PATTERN-MAKER! 
 
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 By G. H. WILLARD 
 
 With Additional Chapters on 
 
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 A book for tbe man who has to do the work. Written 
 by a practical pattern-maker of many years’ experience. 
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 working information. Profusely illustrated. 
 
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 I. Pattern-Making as a Trade. II. The Tools. III. Woods. 
 IV. Joints. V. Turning. VI. Turning (Continued). VII. 
 Turning (Continued). VIII. Turning (Concluded). IX. 
 The Circular Saw. X. The Circular Saw (Continued). XI. 
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 Simple Patterns. XIV. Simple Patterns (Continued). XV. 
 Simple Patterns (Concluded). XVI. Crooked Patterns. 
 XVII. Large Pattern Work. XVIII. Large Pattern Work 
 (Continued). XIX. Crosshead Guide Patterns. XX. Sweep 
 Work. XXI. Pipe Work. XXII. Stove Pattern Work. XXIII. 
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 ■■ Published by - 
 
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Art-Crafts Lamps 
 
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 By JOHN D. ADAMS 
 
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How to Make a 
 
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 By ARTHUR MOORE 
 
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-A NEW BOOK THAT IS NEEDED- 
 
 Power Gas and the 
 Gas Producer 
 
 By J. C. MILLER, M. E. 
 
 An Authentic Text Book and n Complete Reference Manual 
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 ject as the writer. A comprehensive treatise, clear 
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 has therefore been needed for some time. Such is the book 
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READ THIS WONDERFUL STORY 
 
 HEAT 
 
 By J. GORDON OGDEN, Ph.D. 
 
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 This book consists of a series of articles, 
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 Low Temperatures Are Produced. 3—Some Effects of 
 Low Temperature Upon Matter. 4—The Production 
 and Uses of High Temperature. 5—High Tempera¬ 
 tures and the Rare Metals. 6—How Heat Travels. 
 
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n 
 
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 By WM. F. WILLARD 
 
 Formerly Instructor in Mechanical Drawing at Armour 
 Institute of Technology, Chicago 
 
 134 Pages 131 Illustrations Price 50c 
 
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 CHAPTERS ARE DEVOTED TO: 
 
 1. Simple Geometric Exercises and their Application. 
 
 2. Theory of Projections. 
 
 3. Working Drawings and Exercises. 
 
 4. Drafting Room Conventions. 
 
 5. Development of Patterns. 
 
 6 . Penetrations and Developments for Sheet Metal 
 Workers and Tinsmiths. 
 
 7. Value of Isometric Drawings. 
 
 8. Vocabulary of Technical Terms with Definitions. 
 
 9. Equipment and Its Use. 
 
 10. A Model Course for High Schools. 
 
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 Ln ..~. - i l. =3f===^i ni— ; she, 
 
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