bottom chords with the vertical brace members
inches. Measured from the underside of the head,
spaced 6 feet center-to-center; thus, the distance from
lengths range from 1 inch to any length desired.
the centerline of the 4 x 12-inch vertical brace to the
Bolts are threaded, have square heads, and take
centerline of the truss is 24 feet.
square or hexagonal nuts. Bolts are placed through
predrilled holes, with a washer at each end to
b. Members are connected with spikes, bolts,
increase the bearing area on the wood, and are
driftpins, or special timber connectors. The split ring
is the most commonly used special connector. You
should become familiar with all the special
(3) Driftpins. Driftpins are large size
connectors and the identifying symbols used in
spikes from 1/2 to 1 1/4 inch in diameter and from 8
military drawings that are given in figure 2-11. The
to 24 inches long. They are driven into predrilled
specific connector to be used is specified in the bill of
holes of the same diameter or slightly smaller than
the pin diameter.
(1) Spikes. Spikes are used for smaller
(4) Split rings. Split rings are available in
sizes of lumber, as in timber trestle construction, to
2 1/2-, 4-, and 6-inch diameter sizes and are used for
connect horizontal planking to stringers.
making wood-to-wood connections with medium and
heavy loads. A hole must be drilled for the bolt and a
(2) Bolts. Bolts commonly used in timber
groove made for the ring. If columns are built up of
construction vary in diameter from 1/4 to 1 1/4
several pieces (for example, three 2 x 12-inch
Figure 2-11. Timber construction symbols and connectors.