21
4 : Install the Windvane Tower
Braces
The windvane tower is kept vertical by two diagonal
braces made of SS tube 7/8 in. OD supplied with their
appropriate fittings for fastening to the tube at one end. and
to the deck at the other. These braces can be
placed
wherever convenient
to provide adequate support. On the
tower, they are connected with 2 U-shaped curved plates
that are bolted to an inside back-up plate. They should not
be higher than 2 ½ in. below the course adjusting disk, to
allow space for the back-up plate inside the tube.
On the tower, drill two holes dia. 5/16 in. (7 mm), on 1
¾ in. (44 mm) centres at the correct height.
In marking these holes, make sure the
short
horizontal tube
at the base of the tower
lines up perfectly
fore-and-aft
, in the same plane as the mounting tube,
otherwise the moving ring to which it is bolted may bind and
keep the axis from turning freely. If in spite of your
precaution, the ring binds after it has been connected to the
base of the tower, it can be brought back in line by enlarging
the four holes on one side, to allow the tower to pivot until it
is brought back in line. Since the U-shaped bracket covers
the holes, nothing will show.
Bringing the threaded back-up plate
in position inside the tube requires a
little ingenuity
:
At the end of a piece of light line long enough
to reach the bottom of the tower, tie a small nail
around its centre, then feed it through the top hole
until it drops to the bottom of the tube. Pass the
nail through the top hole of the backing plate and
pull it up with the string. When it comes in position,
insert the bottom screw, then remove the nail and
string, and insert the top screw. The back-up plates
are fitted with double-sided adhesive tape, to keep
them in position. Peel off the protecting paper
before installation.
