Figure 2-57.--Applying single lace.

Cotton or linen cord or tape must be prewaxed to make

To fill the shuttle for single lace, measure the cord,

it moisture and fungus resistant. Nylon cord or tape

cut it, and wind it on the shuttle. For double lace,

may be waxed or unwaxed; glass fiber cord or tape is

proceed as before, except double the length of the cord

usually unwaxed.

before winding it on the shuttle, and start the ends on

the shuttle to leave a loop for starting the lace.

The amount of flat tape or cord required to single

lace a group of conductors is about 2 1/2 times the

Some installations, however, require the use of

length of the longest conductor in the group. Twice

twisted wires. One example is the use of twisted pairs

this amount is required if the conductors are to be

for the ac filament leads of certain electron tube

double laced.

amplifiers. This minimizes the effect of radiation of

their magnetic field and helps to prevent annoying

Before lacing, lay the conductors out straight and

hums in the amplifier output. You should duplicate the

parallel to each other. Do not twist them together.

original layout when replacing such twisted leads and

Twisting makes conductor lacing and tracing difficult.

when relating and wiring harness.

A shuttle on which the cord can be wound will

SINGLE LACE.-- Single lace may be started

keep the cord from fouling during the lacing

with a square knot and at least two marling hitches

operations. A shuttle similar to the one shown in figure

drawn tight. Details of the square knot and the marling

2-56 may easily be fashioned from aluminum, brass,

hitch are shown in figure 2-57. Do not confuse the

fiber, or plastic scrap. Smooth the rough edges of the

marling hitch with a half hitch. In the marling hitch,

material used for the shuttle to prevent injury to the

the end is passed over and under the strand (step 1).

operator and damage to the cord.

After forming the marling hitches, draw them tight

against the square knot (step 2). The lace consists of a

Figure 2-56.--Lacing shuttte.

Figure 2-57.--Applying single lace.

Figure 2-58.--Lacing branches and breakouts.

2-50