. Handbook for rangers & woodsmen . olespace or length of span 176 feet. If theline makes a turn at right angles thespaces at either side of the turn shouldnot exceed 100 feet in length. Thissame length of span is also used in spansadjoining one from 300 to 500 feet in length. It is likewise usedin short, sharp curves. Attaching Brackets and Insulators.—Brackets are attached tothe poles at right angles to the ridge of the roof and before thepoles are raised. A 60-D spike is used in the upper hole anda 40-D in the lower, knots, thick rough bark, and other irregu-larities being hewn away if the
. Handbook for rangers & woodsmen . olespace or length of span 176 feet. If theline makes a turn at right angles thespaces at either side of the turn shouldnot exceed 100 feet in length. Thissame length of span is also used in spansadjoining one from 300 to 500 feet in length. It is likewise usedin short, sharp curves. Attaching Brackets and Insulators.—Brackets are attached tothe poles at right angles to the ridge of the roof and before thepoles are raised. A 60-D spike is used in the upper hole anda 40-D in the lower, knots, thick rough bark, and other irregu-larities being hewn away if the brackets are to be attached totrees. Brackets are always so attached that after the poles areset they will be on the outer side of curves, but when the polescarry two Unes then the brackets are placed on exactly oppositesides of the poles. They are fitted with the insulators beforethe poles are raised. See Fig. 27. Holes.—^Except where conditions render it impossible or in-advisable these should have about the following depths:. Fig. 27. Length of pole, in feet. Depth of hole, f Earth., in feet 1 18 22 25 30 35 40 45 i CONSTEUCTION WORK 37 Holes along curves or in loose soil should be at least 6 inchesdeeper than showTi above, and should have a diameter about6 inches greater than that of the pole to be set. If poles mustbe set in sohd rock, it usually proves more economical to drill2- or 3-inch holes and use pipe for poles. Setting.—In setting poles they are turned so the ridge of theroof will be parallel ^dth the line wire, care having been takento roof the crooked poles so the crooks will face the nextpole in the line when the ridge of the roof is parallel with theline. AH poles in straight hues are set as nearly perpendicularlyas possible, but in curves are given a certain amount of rake whichis about as follows: 10 15 20 25 30 (See Fig. 28) 16 24 33 42 (See Fig. 29) Pvdl, in feet. , 5 Rake, in inches 10 Th
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