THE MANUFACTURE OF TEMPERED-CLAY BRICK; INCLUDING A DESCRIPTION OF THE MOST MODERN MACHINERY EMPLOYED.
THE enormous demand for brick in the large cities of the United States has vastly stimulated the invention of all classes of machinery to save labor and to produce quickly large quanti ties of green brick from crude clay.
The proper selection of clays as regards quantity and quality, and the suitable location, construction and economical arrange ment of a brick-making plant, coupled with a practical knowl edge of the art, are the corner-stones of financial success in the business of brick-making.
Cheap transportation of the machinery, building materials, and of fuel to the place of manufacture, and of the brick pro duced, to a profitable market, is necessary, and the question of the existence or non-existence of such facility, either by cart load, by water or by steam, should be thoroughly and minutely examined.
After many plants for the manufacture of brick have been established and the brick made and burned, the question un fortunately is only too often asked : " Have I a suitable market for the brick which I make now and propose to make in the future?" Whether or not you have a sufficient market depends to some extent upon the kind of brick proposed to be manu factured.
If it is proposed to make common building brick entirely, it will be necessary to depend upon home consumption ; i. e., the brick must be sold to be used in the vicinity of where they are produced. With few exceptions, common brick cannot be shipped a great distance with profit, as the freight on a thous and common brick is entirely out of proportion to the amount of money they represent in profits ; and then, too, clays for common building brick can usually be found in abundance near the locality where the brick are to be used, so that the difference in transportation alone may be sufficient in amount to more than overbalance a good profit.
When pressed, ornamental, enameled and the finer classes of brick are to be the principal output of the works, the item of transportation is not such an important feature, for the reason that the freight is not out of proportion to the value of the product.
These facts aid in making for the pressed-brick manufacturer a market extended over a much greater extent of territory than is possible for the maker of common brick.
A manufacturer may make a good quality of brick, and with economy, and fail for the simple reason that the market at command cannot sustain the output from his yard, or from yards in his vicinity.
This has been unfortunately demonstrated in both the brick and drain tile business, especially in Indiana and Illinois.
The recent rapid progress in the art of brick manufacturing has not been accomplished without great loss of money to the pioneers in the movement, and many distressing perplexities.
The transitions from the old and obsolete method have given way to the modern brick-making machinery. To adapt appli ances to work the different clays has been a most costly and harassing experiment ; but at last perseverance and patience have triumphed, and the business of brick-making has reached a safe and reliable basis as regards machinery. It has nearly reached perfection in the economical manner of tempering clay and forming the brick. The tempering wheel has almost dis appeared, and in its stead are a number of good grinders or disintegrators which give satisfaction.
The different kinds of brick machines may be classed under three heads, viz. : 1st, the soft mud ; 2d, the dry-press ; and 3d, the stiff-mud or wire-cut. Each of them has its adherents, and each has its good and bad qualities, and each is best adapted to different clays in different localities.
Probably the three most serious drawbacks in modern ma chinery will be : First, a tendency to over-production. Second, the tendency to make machine-made bricks too large, which greatly increases the cost of manufacture. A suitable and proper size for brick is 23A inches thick, inches wide, 83% inches long. Third, the inducements which machinery offers to inexperienced beginners who engage in the business and make a poor quality of brick, and consequently reduce the price.
It is not the purpose of this work to canvass and give the merits or demerits of any particular machine ; but by saying what has just preceded, merely to hint at a few of the consider ations which should govern those who part with their money for the purchase of either the stock produced, or for a machine itself.
The process of manufacturing brick by machinery may be divided into five stages, viz. : Mining, tempering and preparation of the clay.
Shaping the brick.
Drying.
Setting.
Burning.
Having described the manufacture of dry-clay brick and street-paving brick in separate chapters, those systems will be touched upon in the present one only so far as may be neces sary to illustrate some specific point.