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a point now, where we need to be able to draw the different fixtures, and we there fore show in Figs. 44, 45, and 46, come of this work.
In Fig. 44 we show a side and an end view of a bath tub, for we must be pre pared to show this or any other fixture in either position.
Fig. 45 gives views of a water closet which is general in shape, and unless some particular type is to be shown on a drawing, this form we believe, will be found easier to draw than most any other. For
the different views of these fixtures, and would advise practice in constructing them, first, on the same scale that we show, and then on a larger scale, as it is of course necessary to be able to draw work in any size, and not well to practice continually on the size which we give in the exercises.
After devoting some time to the above practice, we would ask our readers to take up the work shown in Fig. 47, which brings into use the fixtures we are now familiar with, and in certain ways 18
some reason or other, the washout water closet shown in Fig. 46, often appears in plumbing drawings. While saying nothing as to the excellence of this particular type, or otherwise, it is a difficult matter for the beginner in drawing to show it properly proportioned. The incorrect view of Fig. 46 will serve to show some of the common errors made in illustrating this style of closet, which our readers will observe by comparing the same with the upper view.
We have indicated by dots, the centers of the several curves necessary in drawing
somewhat more difficult than preceding exercises. Skill in the drawing of plumbing work is simply a matter of practice, and we therefore again urge upon those following this series, to put in as much practice work as possible. If Fig. 47, or in fact any other work which we present, is on too small a scale for our readers to work easily, with the knowledge of the subject which they now possess, we would advise them to enlarge the size, say to double that which our work shows. It will be noticed in Fig 47, that the Y branch into which the bath and favatory on the
second floor enter, faces toward the front, in which case, we have the view which ap pears. The two vent tees also face the front, so that the tee branch does not appear, merely the circular form of the end of the branch.
Again, the upper fitting in Fig. 47, through which the vent line enters the stack, stands with its branch facing the front, and does not show the true shape of it, such as we have previously given in a preceding chapter.
As we have already stated, in making these drawings, we must be able to show fittings and fixtures in any position that we happen to meet, and while it is best to show them to the best advantage, it is al. most impossible to show every feature of a drawing of any extent, as we would desire.
positions, as seen from the side, and from the front. The front view of this fixture, will be found rather difficult to draw, and to make it as easy as possible, we have dotted the centers of the principal curves used in constructing it. By placing the compasses on the different centers, and seeing which curves would probably be struck from the different points, we think it can be worked out satisfactorily.
In practicing on this work, it may be advisable, as we have previously sug. gested, to work on a larger scale, if the
scale on which plans are illustrated is too small to work easily.
In drawing the front view of the urinai. it will be noticed, by the way, that the fixture is in such a position that the waste is carried directly back. In this case, we might have dotted the waste to the floor, and the back air to the partition, but have preferred to show it in the way that it appears, which we believe will be clear enough for all purposes. There are many places where it is necessary to show part of the work by dotted lines, the dotted lines, of course, always signifying that the work thus shown is behind a wall or other obstruction, but the writer's opinion has always been that in this line of work, dotted lines do not add to the appearance of a drawing, and that it is better not to show them, unless the drawing will be made less clear by omitting them. Up to the present point we have confined ourselves entirely to lead and cast iron work. If we are to be able, however, to draw different kinds of work as it is presented to us, we shall need to know how to show wrought iron piping, not only on supply work, but on back airing. After what instruction has been given on cast iron work, there is not a great deal additional to be given on wrought iron. In Fig. 51, we give two methods of showing fittings, and also the two positions in which valves are usually seen. A side view of the valve shows its true shape, while in an end view the wheel handle and body represent it. In Fig. 52 1s also given a sketch showing errors likely to be made, such as giving too wide a sweep to the curve of an elbow, and in making tee branches too long. A glance at the fittings themselves will show wherein the errors mentioned exist. As to a choice between the use of the beaded fittings and the plain fittings, we believe the former will be found the easiest to draw. The reason for this is that the diameter of the fittings and the diameter of the pipe are usually made the same, while the plain fittings to show as fittings, must have a greater diameter than that of the pipe. and this difference between the laying out of the two styles of fittings means less work on the beaded style.
For this reason, the writer usually pre.
Drawing Showing Urinals in Two