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FIG. 105.

on the platform, if heavy printing frames are used, but this is not usually necessary.

Fig. 105 shows a device for supporting large printing frames. This rests on four caster wheels of not less than 4 inches in diameter. Trunnions are fixed on the sides of the printing frame in a position to exactly balance it, and either the collars of these trunnions should press tightly against the standards, or the trunnions should be considerably larger than those shown, so that the friction will hold the frame in any desired position for printing. The printing frame may be held in a horizontal position for filling by means of the rod pivoted at one end of the frame and having

Large Blueprint Frame. at the other a hook formed upon it which engages a staple in the end of the frame. When in use this frame is rolled to the door of the dark room, the tracing and blueprint paper put in, closed up, and rolled out on the platform, thus avoiding much of the usual manual labor in carrying heavy printing frames.

Where printing must be done out of a window various forms of tracks and frames must be resorted to, but there are many advantages in so locating the blueprint room as to utilize the roof for supporting a large, level platform, as here described. In cases where no monitor roof or similar facilities are offered, and the roof is nearly level, or with a slight pitch, it will be best to build a printing room on the roof with a platform outside of it, so as to be operated as here described.

A simple washing box is provided for soaking blueprints in the usual way. Also, an automatic print washer, as shown in Figs. 106 and 107. In this device a fixed box has pivoted in it a smaller box, whose bottom is composed of light slats. Upon this box is attached, but so as to be removable, a smaller box with a perforated bottom and divided by a transverse partition set exactly in the center. The operation of the device is as follows: The top box being removed by turning the buttons securing it, the blueprints are laid upon the slats, as many as six or eight at a time, and the top box replaced. The water is turned on at the faucet and one end of the pivoted box is depressed to either of the positions shown by dotted lines in Fig. 107, which will throw the water into the compartment at the higher end of the smallest box. A considerable portion of the water will trickle through the small holes of the top box and upon the blueprints, while the opposite ends of the prints are

immersed in the water of the lower box, which is maintained at a constant height by the overflow pipe, as shown in Fig. 107. The perforations in the bottom of the top box not being sufficient to carry off all the water, it gradually fills up that compartment and the pivoted box, thus weighted, is depressed, and the water from the faucets flows into the other compartment and the operation is repeated. The frequency of this rocking movement is easily regulated by the amount of water that flows from the faucet. The operation is not only entirely automatic, but very thorough in its action, as the prints

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lying upon each other are separated and the upper ones float whenever that end is depressed into the water. The water constantly flowing in and out of the lower box readily eliminates the chemicals that are to be washed out of the prints. So far as he knows, the author originated this method for washing blueprints and photograph prints, and used it with much satisfaction. The boxes may be made of wood and kept well painted; or may be of galvanized iron or zinc protected by paint. The original one was made of white pine, the lower box of 14-inch, the pivoted box of 7-inch and the top one of 4-inch stuff, and painted with white lead.

For drying blueprints various devices have been used, but so far as the author knows, nothing is more economical or better adapted to the purpose

than the drying case, or cabinet, shown in Fig. 108. The plan is to attach the blueprints to small, round sticks by means of small wooden spring clips and hang them on supporting brackets. The brackets are of light cast iron or wood, as may be preferred, and should incline on an angle of 45 degrees, so that any print may be conveniently reached and removed without removing those in front of it. Two pairs of these brackets are located, one above the other, for medium sized prints, say 18 x 24 inches, as on the left of the engraving, or one pair for large prints, as shown on the right. The upper section of prints drip the water into a zinc tray supported by a wooden shelf fixed at an angle of 45 degrees, from the lower corner of which, at the back,

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a short pipe carries the water into a similar tray resting on the floor, and from which suitable pipes carry the water to the waste pipes coming from the print-washing apparatus. The drying of blueprints may, of course, be hastened by the application of artificial heat. For this purpose doors may be added to the drying case and a small steam coil be placed in the bottom or near the back of the case. But to use artificial heat, or any temperature over about 100 degrees, has a tendency to cause the prints to be distorted by unequal shrinkage, and marred by wrinkles, while drying them by the natural temperature of the room, and suspended as in this case, will cause them to come out in good condition.

In some large establishments blueprints are made by exposing the blueprint paper and tracing to the action of the light from an electric arc lamp located within a metallic cylinder, in which the paper is fixed, and by

means of which excellent blueprints may be made in large numbers without the aid of sunlight. While the first cost is considerable the work is done

very expeditiously and economically, as the cost of labor is very much reduced. The quality of the work is good, as the lighting is very uniformly distributed over the surface of the sensitized paper.

To adapt this plan of construction and equipping a drawing room to the wants of larger establishments requiring a larger force of draftsmen it is only necessary to extend its length so as to provide for a greater number of the single and double drawing tables, to any extent required. The capacity for filing drawings, tracings, and blueprints should be increased in proportion. One or more large tables for reference drawings will be needed, and the number of lockers increased to accommodate the added force of draftsmen. Otherwise the same arrangement of the plan need not be disturbed, as the chief's room, photographic dark room, vault, and all the other accessories will be either ample or very easily adapted to an increase to any reasonable extent that may be desired.

CHAPTER XX

THE PATTERN SHOP AND PATTERN STORAGE ROOM

Location in relation to the drawing room and machine shop. Capacity of the pattern shop.

The working force necessary. Nature of the product. Equipment of the pattern shop. Location of the machines. Building up segment work. The segment press. The faceplate lathe. The foreman's office. The surface plate. Pattein maker's benches. The work table. The varnishing bench and table. The lockers. The lumber loft over the pattern shop. The lumber drying room. The pattern storage room. System of storing patterns. Pattern storage racks of iron construction. The same of all wood construction. Double width storage racks. Step ladders.

Next to the drawing room, in the usual order of the production of new machines and the development of new plans and ideas into their practical form for commercial purposes, comes the pattern shop, with its proper equipment of woodworking machines, its work benches for the expert workmen, and the conveniences for those associated with them in getting out dimension lumber, and other similar work in connection with it; and closely allied with this department, and really forming a part of it is the pattern storage room, wherein patterns may

be properly catalogued, stored, and issued to the foundry as occasion may require.

In the pattern shop proper the designs of the draftsmen are first brought into tangible form as patterns for the production of those parts to be made of that most common of all materials used in modern construction, namely, cast iron, as well as those for brass, malleable iron, and steel castings.

It is proper, therefore, as well as convenient, that the pattern shop should be placed next to the drawing room. In this case it opens out of it, and has also its convenient passageway to the machine shop by way of a wide door opening upon the machine shop gallery, which, being reached by the large traveling crane, affords a ready means for moving any heavy or bulky articles to and from the pattern shop as readily as to any part of the machine shop.

The pattern shop occupies the space over the tool room and storeroom portions of one of the 50-foot square structures, and extends, also, over the space taken up by the main driveway on the ground floor. It is thus 50 by 70 feet, affording ample space for all the ordinary uses of this department.

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