Practical Plating and Polishing
Contents
- Describes polishing bicycle parts such as handlebars, cranks, and other round or flat components using endless belts and various wheels charged with emery and the firm's Patent Emery Compound for roughing, fining, and finishing.
- Introduces the two sources of current used for electro-plating, dynamo electric machines and batteries, and explains why dynamos have largely superseded batteries as more economical, constant, and free of injurious fumes.
- Describes the dynamo as the best and most economical source of plating current, outlining its principal parts (armature, field magnets, commutator, brushes, brackets, and base) and the features of the firm's Improved American Giant Dynamo.
- Defines the basic electrical units used in plating, the volt (pressure), the ampere (quantity of current), and the ohm (resistance), using a water-pipe analogy to explain their relationship.
- Gives practical instructions for installing and running the dynamo, covering position, belting, speed, oiling, care of the brushes and commutator, and the use of the plug switch to regulate current intensity.
- Explains how to lay out the dynamo, switchboards, and tanks for best results, addressing the arrangement of dynamo and tanks, the size of conductors, and the proper making of joints and connections to minimize lost power.
- Covers the use of batteries for small jobs or where power is unavailable, describing the single-fluid Smee battery and the more powerful two-acid Bunsen battery, plus series, parallel, and series-parallel connection arrangements.
- Explains how switchboards or resistance boards regulate current density and how voltmeters indicate the pressure at each tank, giving the operator full control of the current in the plating room.
- Describes how plating tanks should be built of well-seasoned pine and lined according to the solution used, with asphaltum and pitch for nickel, paraffine for cyanide solutions, and enameled iron for hot cyanide baths.
- Details the polishing of various metals such as cast iron, brass castings, green sand work, and sheet brass and copper, specifying the wheels, emery grades, and polishing compositions used for roughing, fining, finishing, and coloring.
- Sets out the chemical cleaning of metals so that the deposit will adhere, giving step-by-step potash or lye, cyanide, and acid dipping procedures for copper, brass, britannia, steel, cast iron, and stove trimmings.
- Treats nickel plating in detail, describing the double sulphate solution, the placing of anodes, what occurs in the bath during electrolysis, and how the current and anode surface must be managed to keep the solution working properly.
- Gives instructions specific to plating bicycle parts, including stirring the nickel solution to keep the deposit even, plating direct on zinc, and finishing the work by rinsing, drying in sawdust, and buffing after plating.
- Explains copper plating with cyanide solutions, covering cleaning and setting up the bath as for nickel, the time needed to deposit on brass, German silver, iron, and steel, and finishing the work.
- Describes the difficulty of obtaining a reliable cold bronze solution and the method of mixing a red and a white solution in proportion to achieve different shades of bronze plating.
- Covers brass plating, noted as the most troublesome solution to manage, using red and white solutions blended to obtain the desired shade and referring back to the bronze chapter for cleaning and colored plating.
- Explains that silver is the easiest metal to deposit when the solution is made properly from cyanide of potassium and chloride of silver, noting that a large anode surface is unnecessary and anodes should be removed when not in use.
- Describes gold as easily deposited in a wide variety of colors from pure to red gold, run hot or cold, with guidance on adding cyanide of potassium to speed deposition and avoiding too much gold in the solution.
- Covers the electro-deposition of tin, advising a solution kept above 68 degrees Fahrenheit with a current of about two to three volts and pure cast tin anodes, with periodic additions of metal since the anodes do not dissolve in proportion to the tin drawn off.
- Explains galvanoplasty as reproducing non-conducting objects such as leaves, shells, fish, flowers, and insects in copper within an electrotyping solution, with such pieces often afterward plated in gold or silver.
- Describes dips used for oxidizing and coloring metals, including a bright acid dip of vitriol and nitric acid for cleaning brass and a silver oxidizing dip made from sulphuret of potassium.
- Explains lacquers used to prevent metals from tarnishing or oxidizing and to impart colors, describing the transparent and colored films applied to brass, copper, bronze, and silver by dipping or with a camel's-hair brush.
- Describes the materials of the polishing room, including tripoli composition, crocus composition, and emery cake, explaining which metals each is used on for cutting down, coloring, or roughing up.
- Provides general practical and reference information, opening with the transmission of power through hangers, shafting, and pulleys, and including various tables and notes useful to the plater and polisher.
- Lists and describes the principal chemicals of the plating room, beginning with the acids such as sulphuric (oil of vitriol), nitric (aqua fortis), and muriatic acid, with notes on their properties and safe handling.