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METHODS  OF  DIRECT  LINEAR measurements
SUPPORTING  THE  TAPE

Engineering Aid 3 - Beginning Structural engineering guide book
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Grasp  the  100-ft  graduation  on  the  tape  faceup with your left hand. Using your right hand, you take in 5 ft of tape at a time. Place the 95-ft mark over the 100-ft   mark,   next   the   90-ft   mark   over   the   95-ft mark—holding  these  5-ft  marks  firmly  with  the  left hand  so  that  the  tape  will  not  turn  over.  Continue this   operation   for   the   entire   length   of   the   tape, placing each 5-ft division over the preceding one until the  zero  graduation  is  reached,  (Actually,  you  can start   at   either   end   of   the   tape,   whichever   is convenient.)  As  you  are  taking  in  the  tape,  you  will notice that the coils fall  into  the  shape  of  the  figure “8.” (See fig. 12-10.) When you have completed this coiling, square up the tape ribbons. The leather thong at the 100-ft end should be on the underneath side  of  the  coil  next  to your hand. Wrap the thong around the complete coil. Continue wrapping  until  there  is  just  enough  of  the thong left to conveniently insert it through the coil at about  the  50-ft  graduation.  Draw  the  thong  firmly back against the completed windings of the thong. You  can  throw  the  tape  into  a  more  compact circular  roll  by  giving  the  “8”   a  twist,  as shown  in figure  12-11.  Now,  tie  the  tape  with  the  remaining thong. Figure 12-10.-Coiling a tape into a figure “8” form. Figure 12-11.-Throwing the tape into a circular roll. When you wish to use the tape again, reverse the process.  Be  sure  you  let  the  tape  out  from  the  zero end in the same way that it was wound. Walk away from the end of the tape as you  unwind it to prevent kinks. Chaining on Level Ground When   taping   distances   on   a   relatively   level surface and of the third or lower order accuracy, you may  lay  the  tape  on  smooth  ground  or  on  a  paved road or support its ends by taping stools or stakes. In horizontal chaining, the tape is held horizontally, and the   positions    of    the    pertinent    graduations    are projected to the ground by a plumb bob and cord. For ordinary   chaining   on   level   ground,   the   following procedures are generally used: 1. A range pole is set on line slightly behind the point toward which the taping will proceed. The rear chainman, with one chaining pin, stations himself at the starting point of the line to be measured. 2.  The  head  chainman,  holding  the  zero  end  of the  tape  and  with  10  pins  in  his  hand,  then  moves forward   toward   the   distant   point   while   guiding himself with the range pole. Assuming that the tape was already off the reel when they 12-11







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