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main lines of vertical pipe at a distance apart from each other equal to the distance between the two pipes which a view
If these facts do not explain themselves readily to our readers, we would advise them to refer back to what we had to say on projection. We have brought it up at this point in order that our readers may get the idea somewhat in their minds, but shall take it up more thoroughly at a later point in this book. In the same way that the distance between pipes is laid out, other measurements are taken. Thus, looking from the front for the front elevation (Fig. 33), we find the lavatory shown on the first floor plan to be at the right of
Correct and Incorrect Drawing for Fittings. of the house from the front would give.
We wish to make ourselves very clear on this point, as the beginner in drawing often makes a mistake right here. The actual distance between the two lines of pipe as shown in the first floor plan, is the distance from A to C, but in viewing the work from the front, the distance will appear as the distance across from A to B. In the same way in the side elevation the distance between the two pipes will not be the actual distance from A to C, for a view taken by looking at the work from the de ill make the distance appear as that from A to D.
Another Correct and Incorrect method of
Drawing for Fittings. the stack A. Therefore in the elevation, locate it at the same distance to the right of the stack as shown on page 31.
The plans and elevations of any piece of work must always be consistent. Otherwise, they are of no value. The plan of the lavatory just referred to shows that it is set away and from the stack in a certain manner, this we cannot show nearly so well in the elevation. The latter view shows how high the fixture is set, etc., which the plan cannot show. Each view then has its own special use and value. Now let us compare the two elevations. We shall see that the front elevation is far less clear than the side, and so thoroughly is this true, that we have not shown in the connection for the separate fixtures on the front elevation. In the bath room and kitchen the fixtures come in front of each other, and if we should attempt on this small scale to show all the connections, the work would be so confused and mixed up that it would be useless.
The side elevation, however, shows everything clearly. The comparison of the two elevations makes it clear then, that in making an elevation of the plumbing work of any building from the plans, we should be careful to select that elevation which will show the work most clearly. Indeed, it is sometimes necessary to show one stack as a front elevation, and another on the same work as a side elevation. This we shall consider later on.
In Figs. 35 and 36 we give correct and incorrect methods of drawing certain fittings. No. 1, in Fig. 35, shows a T-Y.
The branch is actually a short one and not carried on a wide sweep, with the branch, but so far .out as No. 2 shows. The depth of hubs should be about twothirds the diameter of the pipe.
The vented T-Y is shown in its correct form in No. 3, and should not be made as in No. 4 with the branch hub too far out, and with the branch too leved. The vent hub should be on the same level as the main hub on the fitting.
In Fig. 36 the branch of the inverted Y should be made at 45 deg., and not at 30 deg., as shown in No. 2. No. 3 shows the correct form of the vent fitting used in connecting the main vent back into the stack. The hubs should not be on the same level as No. 4 shows, and the
branch should run out straight for a little distance and not start to curve at once from the main part of the fitting. In Fig. 37 we give two exercises in draw. ing which combine the several fittings shown in the two preceding figures. We would advise some little practice on the work shown in Figs. 35 and 36, and then practice on the work of Fig. 37.
In No. 1 the vent from the upper vent. ed T-Y is shown offset into the main vent through a vent T turned slightly from its straight position. In laying out these two exercises, first put in the two main lines of pipes without hubs, the line of vent being shown nearly its diameter away from the other pipe. The side elevation will receive attention next.
N the preceding chapter we showed
front and side elevations of the plumbing of residence, and
noted the fact that the side elevation was by far the clearer, consequently the more valuable of the two. These views were drawn on the
same scale as the floor plans, and as may have been evident to our readers, this scale was so small that it was more or less difficult to trace out the work, and that the smaller details could not be clearly shown. In Fig. 38 we show the principal part of the side elevation menare made use of. Therefore, many times it is best to show such a view of certain
rig. 38—The Principal Part of Side Elevation Mentioned, Drawn Double Size.
tioned, drawn on a scale of double size.
It will be noticed how much more clearly the work appears. The wiped joints for instance, can be more clearly shown, the beads on the soil pipe hubs, etc. All these minor points go to giving character to a drawing and it is always well to show them.
We would therefore strongly advise our readers against making their draw. Ings on too small a scale. Fig. 38, while double the scale used on the elevations shown in Chapter 6, is too small, and we should have made it larger, but for the necessity of economizing space. The smaller the scale on which a drawing is made, the more difficult, the more puttering the work will be, and it has been the experience of the writer that beginners often discourage their own efforts by drawing their work too small. Another point in connection with Fig. 38, to which we wish to call attention, is the manner in which the main line of back air for the bathroom stack is shown. In Fig. 34 of the previous article, it is shown directly in line with, and in front of the main stack, and this is of course the true position for it in the view in ques. tion.
Instead of following the absolutely right way of showing this line of pipe in Fig. 38 we have shown it at the side of the main stack. A comparison of the two views will show at once that the method followed in Fig. 38 gives a better idea of the way in which the work is done, than Fig. 34. This is particularly true concerning the connection of the main back air into the stack, above the highest and below the lowest fixtures.
In a great many cases, probably a large majority of them, it could make no practical difference whether the relative positions of the stack and main back air were as they are shown in Fig. 34 or as shown in Fig. 38. When this is the case, it will often be found of advantage to draw certain parts of the work as if seen in a different view than the rest. As a general thing, an elevation is usually given simply to show the general layout of the work, the way in which the fixtures are to be connected, etc., and for the location of fixtures the floor plans
Fig. 39-A Practice Sketch