Read Ebook: The Economy of Workshop Manipulation A logical method of learning constructive mechanics. Arranged with questions for the use of apprentice engineers and students. by Richards John

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Mechanical engineering has by the force of circumstances been divided up into branches relating to engineering tools, railway machinery, marine engines, and so on; either branch of which constitutes a profession within itself. Most thorough study will be required to master general principles, and then a further effort to acquire proficiency in some special branch, without which there is but little chance of success at the present day.

To master the various details of machine manufacture, including draughting, founding, forging, and fitting, is of itself a work equal to most professional pursuits, to say nothing of manual skill; and when we come to add machine functions and their application, generating and transmitting power, with other things that will necessarily be included in practice, the task assumes proportions that makes it appear a hopeless one. Besides, the work of keeping progress with the mechanic arts calls for a continual accretion of knowledge; and it is no small labour to keep informed of the continual changes and improvements that are going on in all parts of the world, which may at any time modify and change both machines and processes. But few men, even under the most favourable conditions, have been able to qualify themselves as competent mechanical engineers sooner than at forty years of age.

One of the earliest cares of an apprentice should be to divest his mind of what I will call the romance of mechanical engineering, almost inseparable from such views as are often acquired in technological schools. He must remember that it is not a science he is studying, and that mathematics deal only with one branch of what is to be learned. Special knowledge, or what does not come within the scope of general principles, must be gained in a most practical way, at the expense of hard work, bruised fingers, and a disregard of much that the world calls gentility.

Looking ahead into the future, the apprentice can see a field for the mechanical engineer widening on every side. As the construction of permanent works becomes more settled and uniform, the application of power becomes more diversified, and develops problems of greater intricacy. No sooner has some great improvement, like railway and steam navigation, settled into system and regularity than new enterprises begin. To offset the undertaking of so great a work as the study of mechanical engineering, there is the very important advantage of the exclusiveness of the calling--a condition that arises out of its difficulties. If there is a great deal to learn, there is also much to be gained in learning it. It is seldom, indeed, that an efficient mechanical engineer fails to command a place of trust and honour, or to accumulate a competency by means of his calling.

If a civil engineer is wanted to survey railways, construct docks, bridges, buildings, or permanent works of any kind, there are scores of men ready for the place, and qualified to discharge the duties; but if an engineer is wanted to design and construct machinery, such a person is not easy to be found, and if found, there remains that important question of competency; for the work is not like that of constructing permanent works, where several men may and will perform the undertaking very much in the same manner, and perhaps equally well. In the construction of machinery it is different; the success will be directly as the capacity of the engineer, who will have but few precedents, and still fewer principles, to guide him, and generally has to set out by relying mainly upon his special knowledge of the operation and application of such machines as he has to construct.

How may mechanical be distinguished from civil engineering?-- What test can be applied to determine the progress made in any branch of engineering?-- What are some of the conditions which prevent the use of constants in machine construction?-- Is mechanical engineering likely to become more exact and scientific?-- Name some of the principal branches of mechanical engineering.-- Which is the most extensive and important?

It may in the abstract be claimed that the dignity of any pursuit is or should be as the amount of good it confers, and the influence it exerts for the improvement of mankind. The social rank of those engaged in the various avocations of life has, in different countries and in different ages, been defined by various standards. Physical strength and courage, hereditary privilege, and other things that once recommended men for preferment, have in most countries passed away or are regarded as matters of but little importance, and the whole civilised world have agreed upon one common standard, that knowledge and its proper use shall be the highest and most honourable attainment to which people may aspire.

It may be useless or even wrong to institute invidious comparisons between different callings which are all useful and necessary, and the matter is not introduced here with any view of exalting the engineering profession; it is for some reasons regretted that the subject is alluded to at all, but there is too much to be gained by an apprentice having a pride and love for his calling to pass over the matter of its dignity as a pursuit without calling attention to it. The gauntlet has been thrown down and comparison provoked by the unfair and unreasonable place that the politician, the metaphysician, and the moral philosopher have in the past assigned to the sciences and constructive arts. Poetry, metaphysics, mythology, war, and superstition have in their time engrossed the literature of the world, and formed the subject of what was alone considered education.

In a half century past all has changed; the application of the sciences, the utilisation of natural forces, manufacturing, the transportation of material, the preparation and diffusion of printed matter, and other great matters of human interest, have come to shape our laws, control commerce, establish new relations between people and countries--in short, has revolutionised the world. So rapid has been this change that it has outrun the powers of conception, and people waken as from a dream to find themselves governed by a new master.

Considering material progress as consisting primarily in the demonstration of scientific truths, and secondly, in their application to useful purposes, we can see the position of the engineer as an agent in this great work of reconstruction now going on around us. The position is a proud one, but not to be attained except at the expense of great effort, and a denial of everything that may interfere with the acquirement of knowledge during apprenticeship and the study which must follow.

The mechanical engineer deals mainly with the natural forces, and their application to the conversion of material and transport. His calling involves arduous duties; he is brought in contact with what is rough and repulsive, as well as what is scientific and refined. He must include grease, dirt, manual labour, undesirable associations, and danger with apprenticeship, or else be content to remain without thoroughly understanding his profession.

What should determine the social rank of industrial callings?-- Why have the physical sciences and mechanic arts achieved so honourable a position?-- How may the general object of the engineering arts be described?-- What is the difference between science and art as the terms are generally employed in connection with practical industry?

Were it not that moral influences in learning mechanics, as in all other kinds of education, lie at the bottom of the whole matter, the subject of this chapter would not have been introduced. But it is the purpose, so far as possible, to notice everything that concerns an apprentice and learner, and especially what he has to deal with at the outset; hence some remarks upon the nature of apprentice engagements will not be out of place. To acquire information or knowledge of any kind successfully and permanently, it must be a work of free volition, as well as from a sense of duty or expediency; and whatever tends to create love and respect for a pursuit or calling, becomes one of the strongest incentives for its acquirement, and the interest taken by an apprentice in his business is for this reason greatly influenced by the opinions that he may hold concerning the nature of his engagement.

The subject of apprentice engagements seems in the abstract to be only a commercial one, partaking of the nature of ordinary contracts, and, no doubt, can be so construed so far as being an exchange of "considerations," but no farther. Its intricacy is established by the fact that all countries where skilled labour exists have attempted legislation to regulate apprenticeship, and to define the terms and conditions between master and apprentice; but, aside from preventing the abuse of powers delegated to masters, and in some cases forcing a nominal fulfilment of conditions defined in contracts, such legislation, like that intended to control commerce and trade, or the opinions of men, has failed to attain the objects for which it was intended.

This failure of laws to regulate apprenticeship, which facts fully warrant us in assuming, is due in a large degree to the impossibility of applying general rules to special cases; it may be attributed to the same reasons which make it useless to fix values or the conditions of exchange by legislation. What is required is that the master, the apprentice, and the public should understand the true relations between them--the value of what is given and what is received on both sides. When this is understood, the whole matter will regulate itself without any interference on the part of the law.

The subject is an intricate one, and has been so much affected by the influence of machine improvement, and a corresponding decrease in what may be called special knowledge, that rules and propositions which would fifty years ago apply to the conditions of apprenticeship, will at the present day be wrong and unjust. Viewed in a commercial sense, as an exchange of considerations or values, apprenticeship can be regarded like other engagements; yet, what an apprentice gives as well as what he receives are alike too conditional and indefinite to be estimated by ordinary standards. An apprentice exchanges unskilled or inferior labour for technical knowledge, or for the privilege and means of acquiring such knowledge. The master is presumed to impart a kind of special knowledge, collected by him at great expense and pains, in return for the gain derived from the unskilled labour of the learner. This special knowledge given by the master may be imparted in a longer or shorter time; it may be thorough and valuable, or not thorough, and almost useless. The privileges of a shop may be such as to offset a large amount of valuable labour on the part of the apprentice, or these privileges may be of such a character as to be of but little value, and teach inferior plans of performing work.

On the other hand, the amount that an apprentice may earn by his labour is governed by his natural capacity, and by the interest he may feel in advancing; also from the view he may take of the equity of his engagement, and the estimate that he places upon the privileges and instruction that he receives. In many branches of business, where the nature of the operations carried on are measurably uniform, and have not for a long time been much affected by changes and improvements, the conditions of apprenticeship are more easy to define; but mechanical engineering is the reverse of this, it lacks uniformity both as to practice and what is produced. To estimate the actual value of apprentice labour in an engineering-work is not only a very difficult matter, but to some extent impracticable even by those of long experience and skilled in such investigations; and it is not to be expected that a beginner will under such circumstances be able to understand the value of such labour: he is generally led to the conclusion that he is unfairly treated, that his services are not sufficiently paid for, and that he is not advanced rapidly enough.

With these conclusions in his mind, but little progress will be made, and hence the reason for introducing the subject here.

The commercial value of professional or technical knowledge is generally as the amount of time, effort, and unpaid labour that has been devoted to its acquirement. This value is sometimes modified by the exclusiveness of some branch that has been made the object of special study. Exclusiveness is, however, becoming exceptional, as the secrets of manufacture and special knowledge are supplanted by the application of general principles; it is a kind of artificial protection thrown around certain branches of industry, and must soon disappear, as unjust to the public and unnecessary to success.

In business arrangements, technical knowledge and professional experience become capital, and offset money or property, not under any general rule, nor even as a consideration of which the law can define the value or prescribe conditions for. The estimate placed upon technical knowledge when rated as capital in the organisation of business firms, and wherever it becomes necessary to give such knowledge a commercial value, furnishes the best and almost the only source from which an apprentice can form an opinion of the money value of what he is to acquire during his apprenticeship.

An apprentice at first generally forms an exaggerated estimate of what he has to learn; it presents to his mind not only a great undertaking, but a kind of mystery, which he fears that he may not be able to master. The next stage is when he has made some progress, and begins to underrate the task before him, and imagine that the main difficulties are past, that he has already mastered all the leading principles of mechanics, which is, after all, but a "small matter." In a third stage an apprentice experiences a return of his first impressions as to the difficulties of his undertaking; he begins to see his calling as one that must involve endless detail, comprehending things which can only be studied in connection with personal experience; he sees "the horizon widen as it recedes," that he has hardly begun the task, instead of having completed it--even despairs of its final accomplishment.

In the workshop, mechanical knowledge of some kind is continually and often insensibly acquired by a learner, who observes the operations that are going on around him; he is continually availing himself of the experience of those more advanced, and learns by association the rules and customs of the shop, of the business, and of discipline and management. He gathers the technical terms of the fitting-shop, the forge and foundry; notes the operations of planing, turning, drilling, and boring, with the names and application of the machines directed to these operations. He sees the various plans of lifting and moving material, the arrangement and relation of the several departments to facilitate the course of the work in process; he also learns where the product of the works is sold, discusses the merits and adaptation of what is constructed, which leads to considering the wants that create a demand for this product, and the extent and nature of the market in which it is sold.

All these things constitute technical knowledge, and the privilege of their acquirement is an element of value. The common view taken of the matter, however, is that it costs nothing for a master to afford these privileges--the work must at any rate be carried on, and is not retarded by being watched and learned by apprentices. Viewed from any point, the privileges of engineering establishments have to be considered as an element of value, to be bought at a price, just as a ton of iron or a certain amount of labour is; and in a commercial sense, as an exchangeable equivalent for labour, material, or money. In return a master receives the unskilled labour or service of the learner; this service is presumed to be given at a reduced rate, or sometimes without compensation, for the privileges of the works and the instruction received.

In forming an estimate of the value of his services, an apprentice sees what his hands have performed, compares it with what a skilled man will do, and estimates accordingly, assuming that his earnings are in proportion to what has been done; but this is a mistake, and a very different standard must be assumed to arrive at the true value of such unskilled labour.

Apprentice labour, as distinguished from skilled labour, has to be charged with the extra attention in management, the loss that is always occasioned by a forced classification of the work, the influence in lowering both the quality and the amount of work performed by skilled men, the risk of detention by failure or accident, and loss of material; besides, apprentices must be charged with the same, if not a greater expense than skilled workmen, for light, room, oil, tools, and office service. Attempts have been made in some of the best-regulated engineering establishments to fix some constant estimate upon apprentice labour, but, so far as known, without definite results in any case. If not combined with skilled labour, it would be comparatively easy to determine the value of apprentice labour; but when it comes up as an item in the aggregate of labour charged to a machine or some special work constructed, it is difficult, if not impossible, to separate skilled from unskilled service.

Another condition of apprenticeship that is equally as difficult to define as the commercial value of mechanical knowledge, or that of apprentice labour, is the extent and nature of the facilities that different establishments afford for learners.

In speaking of the mechanical knowledge to be gained, and of the privileges afforded for learners in engineering-works in a general way, it must, of course, be assumed that such works afford full facilities for learning some branch of work by the best practice and in the most thorough manner. Such establishments are, however, graded from the highest class, on the best branches of work, where a premium would be equitable, down to the lowest class, performing only inferior branches of work, where there can be little if any advantage gained by serving an apprenticeship.

Besides this want or difference of facilities which establishments may afford, there is the farther distinction to be made between an engineering establishment and one that is directed to the manufacture of staple articles. This distinction between engineering-works and manufacturing is quite plain to engineers themselves, but in many cases is not so to those who are to enter as apprentices, nor to their friends who advise them. In every case where engagements are made there should be the fullest possible investigation as to the character of the works, not only to protect the learner, but to guard regular engineering establishments in the advantages to be gained by apprentice labour. A machinist or a manufacturer who employs only the muscular strength and the ordinary faculties of workmen in his operations, can afford to pay an apprentice from the beginning a fair share of his earnings; but an engineering-work that projects original plans, generates designs, and assumes risks based upon skill and special knowledge, is very different from a manufactory. To manufacture is to carry on regular processes for converting material; such processes being constantly the same, or approximately so, and such as do not demand much mechanical knowledge on the part of workmen.

The name of having been an apprentice to a famous firm may sometimes have an influence in enabling an engineer to form advantageous commercial connections, but generally an apprenticeship is of value only as it has furnished substantial knowledge and skill; for every one must sooner or later come down to the solid basis of their actual abilities and acquirements. The engineering interest is by far too practical to recognise a shadow instead of true substance, and there is but little chance of deception in a calling which deals mainly with facts, figures, and positive demonstration.

It is best, when an apprentice thinks of entering an engineering establishment, to inquire of its character from disinterested persons who are qualified to judge of the facilities it affords. As a rule, every machine-shop proprietor imagines his own establishment to combine all the elements of an engineering business--and the fewer the facilities for learners, usually the more extravagant this estimate; so that opinions in the matter, to be relied upon, should come from disinterested sources.

In regard to premiums, it is a matter to be determined by the facilities that a work may afford for teaching apprentices. To include experience in all the departments of an engineering establishment, within a reasonable term, none but those of unusual ability can make their services of sufficient value to offset what they receive; and there is no doubt but that premium engagements, when the amount of the premium is based upon the facilities afforded for learning, are fair and equitable.

There is, however, this to be remembered, that the considerations which more especially balance premiums--such as a term at draughting, designing, and office service--may be mainly acquired by self-effort, while the practical knowledge of moulding, forging, and fitting cannot; and an apprentice who has good natural capacity, may, if industrious, by the aid of books and such opportunities as usually exist, qualify himself very well without including the premium departments in his course.

Finally, it must constantly be borne in mind that what will be learned is no less a question of faculties than effort, and that the means of succeeding are closed to none who at the beginning form proper plans, and follow them persistently.

Why cannot the conditions of apprentice engagements be determined by law?-- In what manner does machine improvements affect the conditions of apprenticeship?-- What are the considerations which pass from a master to an apprentice?-- What from an apprentice to a master?-- Why is a particular service of less value when performed by an apprentice than by a skilled workman?-- In what manner can technical knowledge be made to balance or become capital?-- Name two of the principal distinctions between technical knowledge and property as constituting capital.-- What is the difference between what is called engineering and regular manufactures?

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.

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:--

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.

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, 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.

To what general object are all pursuits directed?-- What besides wealth may be objects in the practice of engineering pursuits?-- Name some of the most common among the causes which reduce the cost of production.-- Name five of the main elements which go to make up the cost of engineering products.-- Why is commercial success generally a true test of the skill connected with engineering-works?

Machines do not create or consume, but only transmit and apply power; and it is only by conceiving of power as a constant element, independent of every kind of machinery, that the learner can reach a true understanding of the nature of machines. When once there is in the mind a fixed conception of power, dissociated from every kind of mechanism, there is laid, so to speak, a solid foundation on which an understanding of machines may be built up.

To believe a fact is not to learn it, in the sense that these terms may be applied to mechanical knowledge; to believe a proposition is not to have a conviction of its truth; and what is meant by learning mechanical principles is, as remarked in a previous place, to have them so fixed in the mind that they will involuntarily arise to qualify everything met with that involves mechanical movement. For this reason it has been urged that learners should begin by first acquiring a clear and fixed conception of power, and next of the nature and classification of machines, for without the first he cannot reach the second.

Machinery can be divided into four classes, each constituting a division that is very clearly defined by functions performed, as follows:--

Or, more briefly stated--

Motive machinery. Machinery of transmission. Machinery of application. Machinery of transportation.

These divisions of machinery will next be treated of separately, with a view of making the classification more clear, and to explain the principles of operation in each division. This dissertation will form a kind of base upon which the practical part of the treatise will in a measure rest. It is trusted that the reader will carefully consider each proposition that is laid down, and on his own behalf pursue the subjects farther than the limits here permit.

To what three general objects are machines directed?-- How are machines distinguished from other works or structures?-- Into what four classes can machinery be divided?-- Name one principal type in each of these four divisions.

In this class belong--

Steam-engines. Caloric or air engines. Water-wheels or water-engines. Wind-wheels or pneumatic engines.

These four types comprehend the motive-power in general use at the present day. In considering different engines for motive-power in a way to best comprehend their nature, the first view to be taken is that they are all directed to the same end, and all deal with the same power; and in this way avoid, if possible, the impression of there being different kinds of power, as the terms water-power, steam-power, and so on, seem to imply. We speak of steam-power, water-power, or wind-power; but power is the same from whatever source derived, and these distinctions merely indicate different natural sources from which power is derived, or the different means employed to utilise and apply it.

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