Figure 3-77 shows a few of the many specialized
nails. Some nails are specially coated with zinc,
cement, or resin materials. Some have threading for
increased holding power of the nails. Nails are made
from many materials, such as iron, steel, copper,
bronze, aluminum, and stainless steel.
Annular and spiral nails are threaded for greater
holding power. They are good for fastening paneling
or plywood flooring.
The drywall nail is used for
hanging drywall and has a special coating to prevent
rust. Roofing nails are not specified by the penny
system; rather, they are referred to by length. They
are available in lengths from 3/4 inch to 2 inches and
have large heads.
The double-headed nail, or
duplex-head nail, is used for temporary construction,
such as form work or scaffolding. The double head
on this nail makes it easy to pull out when forms or
scaffolding are torn down. Nails for power nailing
come in rolls or clips for easy loading into a nailer.
They are coated for easier driving and greater holding
power. Table 3-10 gives the general size and type of
nails preferable for specific applications.
Staples are available in a wide variety of shapes
and sizes, some of which are shown in figure 3-78.
Heavy-duty staples are used to fasten plywood
sheeting and subflooring. Heavy-duty staples are
driven by electrically or pneumatically operated tools.
Light-duty and medium-duty staples are used for
attaching molding and other interior trim. Staples are
sometimes driven in by hand-operated tools.
The use of screws, rather than nails, as fasteners
may be dictated by a number of factors. These may
include the type of material to be fastened, the
requirement for greater holding power than can be
obtained by the use of nails, the finished appearance
desired, and the fact that the number of fasteners that
can be used is limited. Using screws, rather than
nails, is more expensive in terms of time and money,
but it is often necessary to meet requirements for
superior results. The main advantages of screws are
that they provide more holding power, can be easily
tightened to draw the items being fastened securely
together, are neater in appearance if properly driven,
and can be withdrawn without damaging the material.
The common wood screw is usually made of
unhardened steel, stainless steel, aluminum, or brass.
The steel may be bright finished or blued, or zinc,
cadmium, or chrome plated. Wood screws are
threaded from a gimlet point for approximately
two-thirds of the length of the screw and are pro-
vided with a slotted head designed to be driven by
an inserted driver. Wood screws, as shown in
figure 3-79, are designated according to head style.
The most common types are flathead, oval head, and
Figure 3-77.-Specialized nails.
Figure 3-78.-Types of staples.