Building Design and Construction Handbook - Merritt - Ventech!

WALL, FLOOR, AND CEILING SYSTEMS 11.139
driven with width parallel to grain of wood, they have less tendency to split wood
than wire nails.
The length of cut and wire nails is designated by the unit ‘‘pennies.’’ Both cut
and wire nails come in sizes from 2-penny (2d) which are 1 in long, to 60-penny
(60d), which are 6 in long. Above 6 in, the fasteners are called spikes. They run
in 7-, 8-, 9-, 10-, and 12-in lengths.
Various gages or thicknesses of nails, and different sizes and shapes of heads
and points (Figs. 11.84 and 11.85), are available in both wire and cut nails. Certain
types have distinguishing names. For example, the term brads is applied to nails
with small heads, suitable for small finish work.
Common brads are the same thickness as common nails but have different
heads and points. Clout nails have broad flat heads. They are used mostly for
securing gutters and metalwork.
Casing nails are about half a gage thinner than common wire nails of the same
length; finishing nails, in turn, are about half a gage thinner than casing nails of
the same length. Shingle nails are half a gage to a full gage thicker than common
nails of the same length.
Certain manufacturers have developed nails for special purposes that hold tighter
and longer. Among these are threaded nails (Fig. 11.84), which combine the ease
of driving of the ordinary nail with much greater holding power.
One type is a spiral-threaded flooring nail. These nails turn as they drive, minimizing
splitting of the tongues of the floor boards. These nails are said to actually
grip more firmly with the passage of time. A nailing machine is available for driving
these nails. In one operation, it starts the nail, drives the joint between the flooring
strips tight, and drives and sets the nail. With this machine, mashed tongues and
marred edges of the wood are avoided.
Nails of aluminum and stainless steel are particularly useful in exposed locations
where rust or corrosion of steel nails might cause unsightly stains to form on
exterior finished surfaces. These nails are now made in most of the usual sizes,
including special spiral-threaded nails.
Galvanized nails are used for fastening slate and shingles. These nails are sometimes
used in exposed locations as protection against corrosion.
11.71 SCREWS
These are used for applying hardware of all descriptions; also for panel work,
cabinet work, all types of fine finish work, and support of electric and plumbing
fixtures. Screws have greater holding power than nails and permit easy removal and
replacement of parts without injury to the wood or finish. Screws avoid danger of
splitting the wood or marring the finish, when the screw holes are bored with a bit.
Screws are made in a large variety of sizes and shapes to suit different uses (Fig.
11.86) and they are made of different metals to match various materials. A muchused
type of head, other than the ordinary single-slot type, is the Phillips head,
which has two countersunk slots at right angles to each other. The head keeps the
screwdriver exactly centered during driving and also transmits greater driving power
to the screw, while holding the screwdriver firmly on the head. Phillips heads are
smoother at the edges, because the slots in the head do not extend to the outer
circumference.