An analysis of japanning practice as a systematized industrial operation is presented as the result of an investigation. The nature of japans is discussed and an outline given of how the apparently contradictory requirements that japans must be weatherproof, somewhat flexible, sufficiently thick to be lasting, possess enough hardness to prevent excessive scratching under ordinary service conditions and take on a brilliant finish, can be fulfilled in an ordinary industrial plant without undue expenditure, so as to accomplish the original and primary objects of applying a finish to metal parts to prevent them from too great deterioration and supply a pleasing appearance to the finished product.
Adequate provision for securing a uniform product is essential. The details of this are discussed. Three ways of applying japan are explained. The considerations involved in cleaning the metal and baking japan are enumerated at some length and the methods are described. Japanning plant equipment, including japan storage and handling, a mechanical conveyor, cleaning and baking apparatus, is then commented upon at length, the thought then passing to a detailed consideration of heating methods. This is followed by data and discussion regarding the temperature control and mechanical construction of japanning ovens.