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Page:Popular Science Monthly Volume 89.djvu/455

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Popular Science MonlhJy

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��the pipe above the bolt. From his position on the platform, the erector ciin easily raise the pipe hand over hand until it is high enough to couple on to the second section in the manner shown in Fig. 5. The two coupled sections are then raised until the coupling is just above the collar, where they are tempo- rarily suspended by a hook inserted in the bottom pipe, and the second set of three guy-wires attached.

Handling the Guy-Wires

From this point on it will be necessary to enlist the services of neighbors to hold and pay out guy-wires. The two sections are raised in the same manner high enough to couple on the third sec- tion. After this it will be necessary to resort to block and tackle. A good way to use this is shown in Fig. 8, in which it should be noted that the temporary arm, made of two 5-foot pieces of 2-inch by 4- inch, straddles the pipe and is securely guyed in its position at the rear.

��platform supports and the timber as in- dicated. A rope hitch around the i)ipe serves to lower it gradually into the hole, after which the guy-wires are trued u[3 and the mast is complete.

In Fig. 4 is shown how the guys may be spread in si.x directif)ns. It will be found very desirable to break the guy- wires up into short lengths to prevent absorption of energy. Ordinary porce- lain knobs are quite satisfactory for this purpose. Buried logs make excellent guy anchors ; they should be set well out from the base of the pole.

The Mast Will Resist Storms

This makes a strong, serviceable, neat- appearing mast. The writer has one, erected over a year ago. Standard coup- lings instead of pipe sleeves are used be- tween the joints, which support a heavy 200-meter aerial made of No. 9 solid copper wires. It has successfully with- stood several 60-mile squalls, besides some exceptionally heavy sleet storms.

���The pressure brought to bear on the arm is all down- •ward, and a few nails through a block between the members will hold it in place temporarily. Tackle is rigged between this arm and a single block in the bottom of the pipe, and the three sections of pipe are easily raised. The third set of guy-wires is to be at- tached as soon as the last joint gets above the collar.

Bolting the Pipe in Place

The bottom of the pipe is fastened to the side of the pole at the height of the platform, by resting it on the block shown in Fig. 6. This may be of 6-inch by 6-inch cypress, 2 feet long, and is hollowed out on the side next the pole to receive the pipe as shown. It is securely bolted to the

��Fig. 8. Showing Rigging of Temporary Arm for Final Lift

��Top View of Temporary Arm This Arm Straddles the Pipe Securely Guyed at the Rear

��The design herein set forth is of course flexible, and the build- er can easily add an additional 20-footsec- tion of pipe if desired.

The round pipe of- fers much less resist- ance to the wind than wood timbers of equal strength, and as it is well insulated from the ground, there is little or no loss from this cause.

It would be well to pro\ide a grounding switch for lightning protection on the side of the timber near the ground, connected with the pipe by a heavy copper wire, Init this is not abso- lutely necessary.

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