Figure 13. Marking Paper Under Left Spring Shackle

TB 9-2300-247-40

Refer to Figure 14. Measure the distance

NOTE

between the left side plumb bob mark (1)

For accuracy, do not make mark on

and string (2) on shop floor.

paper until plumb bob has stopped

swinging, is motionless, and is as

If the distance is more than 1/4-inch, the

close to the paper as possible

frame rails (3) are out of tolerance.

without actually touching the paper.

Record measurements.

Refer to Figure 13. Carefully mark a spot

(5) on paper (4) directly below plumb bob

point (3).

Figure 14. Measuring Frame Squareness