. American telephone practice . formed up of sheet steel with reinforced edges. The reinforcementsare formed by rolling the metal into hollow cylinders along theedges of the brace. This seems meritorious in that it is lighter than 776 AMERICAX TELEPHONE PRACTICE. the regular solid brace and is said to be stronger and cheaper. Itwould, apparently, however, be more liable to rust through. Thisbrace and the usual method of using braces are shown in Figs. 541and 542, respectively. In all cases suitable washers should be used under carriagebolt nuts and heads, and under lag-screw heads where they a
. American telephone practice . formed up of sheet steel with reinforced edges. The reinforcementsare formed by rolling the metal into hollow cylinders along theedges of the brace. This seems meritorious in that it is lighter than 776 AMERICAX TELEPHONE PRACTICE. the regular solid brace and is said to be stronger and cheaper. Itwould, apparently, however, be more liable to rust through. Thisbrace and the usual method of using braces are shown in Figs. 541and 542, respectively. In all cases suitable washers should be used under carriagebolt nuts and heads, and under lag-screw heads where they are usedin attaching an arm to the pole. All hardware to be used on poles,such as bolts, washers, braces, etc., should be thoroughly galvanizedand should be made to stand the same test that is required on gal-vanized iron wire—that is, four successive plunges of seventy sec-onds each in a saturated solution of sulphate of copper without re-moving all of the zinc coating. The pins most commonly used are of locust or of oak. The.
Size: 1020px × 2450px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., boo, bookcentury1900, bookdecade1900, bookidamericantelepho00mill
