strip as close as possible to its forward end, and make rear contact at this point. Use a pair of dividers
and a millimeter scale to measure the distance between the two scratches on the rear metal strip. Add
this distance to the length of the baseline. This operation is known as setting forward or setup. The
opposite situation occurs when the forward graduations overshoot their post. This operation is known as
setting backward or setback.
(2) The recorder ensures that no blunders are committed, such as dropping or adding a tape
length or recording a half-tape length as a full tape. He must check the chalked numbers on each stake
as it is reached to ensure that he completes all the notes necessary for a definite and correct
interpretation of the record. He must check the measurements of setups and setbacks and have the
contact man check the entry in the record book.
d. The front stretcher man applies the proper tension to the tape by means of a tape stretcher with a
spring balance attached to the forward end of the tape (Figure 3-1). A tape stretcher consists of two
staves of steel tubing, pointed at the bottom, and wooden tops. A loose-fitting leather loop, with an
attachment to receive the looped end of the tape, slips over the staff at the rear end of the tape. A frame
for holding the spring balance is attached to the forward staff by means of a spring friction grip. In
moving forward, the front stretcher man carries the front stretcher and balance, detached from the tape.
As the tape is brought forward into position, he holds the spring balance hook in such a position that the
tape can be quickly attached. As the tape is attached, he places the staff in line with the stakes, at the
proper distance from the front stake, and applies the tension. The tension is applied rapidly at first and
is increased gradually as he nears the 15-kilogram point. Under tension, the tape must clear the top of
the forward stake and not drag over it; otherwise, the full tension will not be transmitted throughout the
tape.
Figure 3-1. Tape Stretcher and Spring Balance
EN0593
3-6
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