tection when drilling
.
Avoid nails, they ruin
bits and they can create injury. Pay particu-
lar care when using “hole-hogs” and other
powerful electric drills; the torque of the
drill when suddenly stopped by a nail can
break the wrist of a strong man.
Drilling
Use a bit that is large enough for the wires
you plan to run. An auger bit is the pre-
ferred bit for rough-in wiring. It will actu-
ally pull itself through the wood, so that
the drill motor, not you, does most of the
work. You may be drilling a lot of holes,
so this is an important consideration.
Always drill the holes in the center of the
stud. If you have to notch the stud or drill
the hole closer than one inch from the
edge of the stud, protect the wire with a
nail plate
(See Figure 7)
.
When drilling holes in ceiling joists drill in the
center of the joists and try to locate the hole
near the end of the joist. DO NOT drill
through a “gluelam” or any load bearing beam
without the direction of your contractor.
Try to line the holes up perfectly, because
it makes pulling the wire much easier. A
good technique is to snap a chalk line
across the face of the studs or against the
bottom of the ceiling joists. Then work
backward so that you can always see the
holes you have already drilled. Paying
careful attention to this will save you a lot
of time later on!
Pulling the Cable
Pull the cable in sections (from the stereo
to the volume control, from the volume
control to the speaker). Start with the
longest sections and use left over wire to
complete the short sections. If you plan to
pull many rooms at the same time through
a central route, walk off the distance to
each destination, add a generous fudge
factor for turns and other obstacles, then
cut off each section so that you have a
bundle of wires you can pull at once.
Whenever you run the wire further than
four and one half feet from a hole in a stud
or joist (open attic space, going up walls,
etc.), fasten the wire to the joists or studs
using cable clamps or appropriately sized
wire staples. The wire should not have
large sags in it, nor should it be too tight.
Try to protect the wire from being stepped
on in attics or other unfinished crawl
spaces. There are guard strips, raceways
and conduits which can be used to protect
the cable. Consult the local building code
for special requirements in your area.
Concealing Speaker Wire
in Existing Walls
This is actually a fairly simple task if you
restrict your choice of speaker locations
and wire routes to the interior walls or
ceilings of your home. Interior walls in
almost all North American residences are
hollow, so that it is easy to flush mount
speakers into them and route new speaker
cable around the house. What you see
when you look at the painted wall board,
plaster, or paneling is only the skin of the
wall. Behind the skin is the skeleton; two-
by-four wood or metal “studs” running
vertically from the floor to the ceiling in
walls and two-by-six or larger “joists” run-
ning horizontally in the ceilings and
floors. In between the studs and the joists
is the space for the wiring and plumbing
of your home.
Exterior walls are different. They must
insulate the house from the heat and cold
outside, so they are stuffed with insulation.
The national building code requires that
the hollow wall space in exterior walls be
broken by a horizontal stud placed
between the vertical studs. This “fire
blocking” makes it very difficult to retrofit
long lengths of wire. In some areas of the
country the exterior walls are constructed
10
Ins
talla
tion F
undamen
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