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CHAPTER XXI. The Consideration of a Six-Flat Apartment House, Cellar and Floor Plans, Kitchen and Bath
106 CHAPTER XXVI. Method of Showing Steam Pipes on Floor Plans. The Drawing of Piping in Perspective. ... 109
Mechanical Drawing for Plumbers
HE man who to-day does high-class the obtaining of good work can be traced
plumbing or heating, and is directly to the fact that a neat little worthy the name of doing that sketch of the proposed work was submit
class of work, is as deserving of ted to the owner. The sketch showed that credit as is the lawyer who conducts the one who presented it was up-to-date, his
court successfully, and knew his business, and that thereby the physician who performs the duties he gained a better place in the opinion that devolve on him in creditable manner. of his customer than his competitor, was The trade, we must remember, is not in to be expected. the crude state that it was years ago, And it is these little points that count, and if the plumber keeps abreast of the not merely to-day, but always in the years times, he must educate himself along sev to come. eral lines in addition to the manual side In many sections of the country, par. of the question. He must be conversant ticularly where the work is of a high to some extent with chemistry, and the grade, the master and the journeyman subject of physics, that is, natural law, must as a part of the examination make is more valuable to him than to any a drawing of some system of plumbing. other man that we can think of. If he is Another quite general custom nowadays to make the most of himself and his op is the demand by boards of health, that portunities, the progressive man cannot the plumber applying for a permit to do do better than to take up the study of work, shall first submit drawings of the mechanical drawing, at least so far as proposed work. it concerns the laying out of plumbing How convenient, and even profitable, to and heating work. A knowledge of the be able to submit work on such occasions subject is valuable, not only to the man we have just cited, which shall be who is conducting a business and uses creditable. In visiting the different sechis knowledge in demonstrating his ideas tions of the country, it has been impressto the prospective customer, but even the ed upon the writer's mind that there is apprentice cannot afford to be ignorant a great demand for a knowledge of this of it, for on paper he can lay out work, subject, a demand which has not yet been run his lines of pipe and make his con met. nections-all in a practical way-and The correspondence school fills a longgain experience thereby that he cannot felt want, and we believe it to be a valugain in serving at the trade unless more able institution, but ofttimes a busy man fortunate than his brothers in the ad does not feel that he can spare the time vantages that are given him.
necessary to such a course as given by The writer has in mind instances where them, which necessitates the taking up ol
several branches of study as a means of covering the whole ground. While we would not dignify our present series of articles as a “course in drawing," it is our intention to make it serve as such, as near as possible.
It will be appreciated that the subject is a difficult one to present, as it is best studied under an instructor who can correct an error on the spot, and explain fully wherein the error lies.
We would say, that in pursuing this series, it is with the idea of making it
As to instruments, unless it is desired to take up the inking of drawings, the only instruments actually needed are a pair of compasses for making large circles, and a pair of bow compasses for small circles. The latter instrument is of special value in making neat work.
In Fig. 1 we show the drawing board, with the tee square in position, also both triangles. In Fig. 2 the large compasses are shown, and in Fig. 3 the bow, or spring compasses.
The tee square and triangles may be of
Figure 1 of real practical value to those of our wood, for ordinary use. Celluloid trireaders who are interested in the subject, angles are especially good, as the work as we believe that every master plumber beneath shows through them. and steam fitter should thoroughly under It is no doubt well known to our readstand the manner to draw at least in a ers that horizontal lines are made along crude way the plans for work on which the edge of the tee square and vertical he may estimate.
lines are made along the edge of the triAs a preliminary to pursuing the sub angle held against the edge of the tee ject of drawing, the student should pro square. With triangles which are true, vide himself with the necessary tools, this insures true work, but if the vertical which include the drawing board, tee lines are made by holding the tee square square and triangles (30 deg. and 45 deg.) against the lower edge of the board, there and a small set of instruments.
is very little chance of the work being
true, that is square, for there is seldom a drawing board that will be found exactly square all round.
In entering upon the subject of mechanical drawing, whether it is such
tical worth to the plumber, as far as lay. ing out his own work is concerned.
To show the fundamental principle of projection, let us consider the object which we show in Fig. 4, an ordinary pyramid.
Now suppose we consider this object surrounded by transparent surfaces, glass plates for instance, as shown in Fig. 5. We will suppose that the object is viewed from three different directions, from the front, from the side, and from the top. If we consider that the rays of light from each point, as these three views are taken, reach the eye at right angles to the respective glass plates, and draw on those plates the view of the object as it appears to us, we shall have what is known in mechanical drawing as
Bow Compasses actual
Fig. 2 drawing as the plumber, the machinist, or the architect would need, it is necessary to understand the principles of projection which in reality underlies the whole subject. All working drawings, which show several views of the same object, such as are used in every machine shop, are worked out by projection, and in this class of work it is applied much more extensively than on the work in which we are interested.
With us, it will not be necessary to take up any but the most elementary principles, for although valuable to any man, the more advanced principles of projection would not be of much prac
Fig. 3 the top view or plan, and the front and side views, or elevations, as they are commonly called. In other words, the eye is supposed to sight the object at right angles at every point at one time.