mechanical engineering, like every other business pursuit, is directed to the accumulation of wealth; and as the attainment of any purpose is more surely achieved by keeping that purpose continually in view, there will be no harm, and perhaps considerable gain derived by an apprentice considering at the beginning the main object to which his efforts will be directed after learning his profession or trade. so far as an abstract principle of motives, the subject is of course unfit to consider in connection with engineering operations, or shop manipulation; but business objects have a practical application to be followed throughout the whole system of industrial pursuits, and are as proper to be considered in connection with machine-manufacturing as mechanical principles, or the functions and operation of machines.
the cost of production is an element that continually modifies or improves manufacturing processes, determines the success of every establishment, and must be considered continually in making drawings, patterns, forgings, and castings. machines are constructed because of the difference between what they cost and what they sell for—between their manufacturing cost and market value when they are completed.
it seems hard to deprive engineering pursuits of the romance that is often attached to the business, and bring it down to a matter of commercial gain; but it is best to deal with facts, especially when such facts have an immediate bearing upon the general object in view. there is no intention in these remarks of disparaging the works of many noble men, who have given their means, their time, and sometimes their lives, to the advancement of the industrial arts, without hope or desire of any other reward than the satisfaction of having performed a duty; but we are dealing with facts, and no false colouring should prevent a learner from forming practical estimates of practical matters.
the following propositions will place this subject of aims and objects before the reader in the sense intended:—
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first. the main object of mechanical engineering is commercial gain—the profits derived from planning and constructing machinery.
second. the amount of gain so derived is as the difference between the cost of constructing machinery, and the market value of the machinery when completed.
third. the difference between what it costs to plan and construct machinery and what it will sell for, is generally as the amount of engineering knowledge and skill brought to bear in the processes of production.
this last sentence brings the matter into a tangible form, and indicates what the subject of gain should have to do with what an apprentice learns of machine construction. success in an engineering enterprise may be temporarily achieved by illegitimate means—such as misrepresentation of the capacity and quality of what is produced, the use of cheap or improper material, or by copying the plans of others to avoid the expense of engineering service—but in the end the permanent success of an engineering business must rest upon the knowledge and skill that is connected with it.
by examining into the facts, an apprentice will find that all truly successful establishments have been founded and built upon the mechanical abilities of some person or persons whose skill formed a base upon which the business was reared, and that true skill is the element which must in the end lead to permanent success. the material and the labour which make up the first cost of machines are, taking an average of various classes, nearly equally divided; labour being in excess for the finer class of machinery, and the material in excess for the coarser kinds of work. the material is presumed to be purchased at the same rates by those of inferior skill as by those that are well skilled, so that the difference in the first, or manufacturing cost of machinery, is determined mainly by skill.
skill, in the sense employed here, consists not only in preparing plans and in various processes for converting and shaping material, but also in the general conduct of an establishment, including estimates, records, system, and so on, which will be noticed in their regular order. the amount of labour involved, and consequently the first cost of machinery, is in a large degree as the number of mechanical processes required, and the time consumed in each operation; to reduce the number of these processes or operations, shorten the time in which they may be performed, [27] and improve the quality of what is produced, is the business of the mechanical engineer. a careful study of shop operations or processes, including designing, draughting, moulding, forging, and fitting, is the secret of success in engineering practice, or in the management of manufactures. the advantages of an economical design, and the most carefully-prepared drawings, are easily neutralised and lost by careless or improper manipulation in the workshop; an incompetent manager may waste ten pounds in shop processes, while the commercial department of a work saves one pound by careful buying and selling.
this importance of shop processes in machine construction is generally realised by proprietors, but not thoroughly understood in all of its bearings; an apprentice may notice the continual effort that is made to augment the production of engineering-works, which is the same thing as shortening the processes.
a machine may be mechanically correct, arranged with symmetry, true proportions, and proper movements; but if such a machine has not commercial value, and is not applicable to a useful purpose, it is as much a failure as though it were mechanically inoperative. in fact, this consideration of cost and commercial value must be continually present; and a mechanical education that has not furnished a true understanding of the relations between commercial cost and mechanical excellence will fall short of achieving the objects for which such an education is undertaken. by reasoning from such premises as have been laid down, an apprentice may form true standards by which to judge of plans and processes that he is brought in contact with, and the objects for which they are conducted.
(1.) to what general object are all pursuits directed?—(2.) what besides wealth may be objects in the practice of engineering pursuits?—(3.) name some of the most common among the causes which reduce the cost of production.—(4.) name five of the main elements which go to make up the cost of engineering products.—(5.) why is commercial success generally a true test of the skill connected with engineering-works?
