Evening star., 1934-04-28
LUMbERMEN HAIL
NEW RADIO TOWER
Provides Construction Form
That Permits Use of
Wood Connector.

The new single radio tower OF
station WEBC, Superior, Wis, which
rises $50 feet above Lake Superior
fats, may be the pioneer of a new
method of timber construction, as the
modern timber connector" device,
which marks the design of the tower,
is said to make wood rival of steel
in many types of structural frames.
The new shaft. built by Roland c.
Buck, Inc, engineers, to hold WEBC's
vertical antenna, attains its $50 feet
by the placing of the stations old
230-foot steel structure upon a new
l20-foot tower built of wood. the cor
ners of which rest upon concrete piers
embedded in the ground. The wooden
tower is 35 feet square at the ground
and taperS up to IL feet square at
the point where the old tower is
joined.
Idea Born in Europe.
Modern timber connectors were re-
Gently introduced into this country
from Europe by the National Commit
tee on Wood Utilization, now part of
the Forest Products Division of the
United States Department of Com
merce. They consist in general of
steel rings or bowels, which are
pressed into the opposing surfaces of
two connecting wooden pieces, and
support and transmit load from one
structural member to another. For
merly this function was served by the
bolts which faSten the pieces to-
gether. The bolts are retained. but
the connectors carry the load. There
are more than 60 kinds of connetcorS
in use abroad and several have be-
come commercially important. These
include the split-ring type, which is
inserted in circular groove surround
ing the bolt hole. and the alligator
type, which is forced into the wood as
the tightening of the bolt draws the
two pieces together.
The advantages of using this wood
en- radio tower are low cost of con-
struction and a high degree of insula-
tlon. w. G. Bridges, general manager
of the Observation-Disclosures Broadcast
ing Co., which operates WEBC, de-
clared in letter regarding the opera
ton of the new tower: The results
have far exceeded our expectations.
Several atwood radio towers have
been constructed, and the highest
wood tower in the world has Just
been completed at Muehlacker, Ger
many. This tower is 100 meters, or
about 625 feet in height and supports
at the top an antenna ring 10 feet
in diameter, weighing 1920 pounds.
Used in Other Ways.
The use of connector construction
is by no means limited to radio
towers. 1t has facilitated and re-
duced the cost of erection of oil
derricks. wharves and piers, a man.
moth dirigible hangar, 200-foot tim
ber roof arches, and other structures
which, prior to the advent of tim
Der connectors, were considered i'm
practicable for wood construction.
The connector system makes joints
two to three times as strong as can
be made with bolts alone, gives wooden
structures rigidity not otherwise
obtainable. 1t has been described by
DR.. Wilson Compton, general man
ager of the National Lumber Manu-
facturers' Association, las the most
important development in wood con-
structlon in a century"
Among other recent installations
are seven 100-foot fire lookout
towers for the United States Forest
Service, erected at the same number
of places in the United States. and
still another of 60 feet. Timber con-
nectors were recently used for the
construction of an 80-foot fire look
out tower for the Florida State For
est Service at Dinsmore, Fla, for an
overhead highway bridge built for the
California State Highway Commission
at Preston, Calf; rock, sand, and
gravel bunkers for the Charles E.
Hughes Co., at Berkeley, Calf, and the
Clark Riding Hall at Upperville, Va,
the roof of which rests upon seven
60-foot Fink trusses made with the
aid of timber connectors
In ALL 60 structures, using tens of
thousands of modern timber con-
nectors and approximately 5,5O0OOO
board feet of dimension and timbers,
have been built in the United States
in the last eight months. The woods
used are largely red cypress. Douglas
fir, larch. Southern pine and Cali
fornia redwood.