Hex Beam by K4KIO
Site publication date
12/2007
Step One - Baseplate and Center post

  • The baseplate is made of a 12 inch square type 6061 T6 aluminum plate that is 3/16 inch thick. It was
    obtained from www.onlinemetals.com. They sell small quantities and at reasonable prices. This
    particular type aluminum is harder than pure aluminum and less likely to bend while being resistant to
    weather. U-bolts are used to attach the spreaders to the baseplate.

  • The center post is 1 1/4 inch O.D. fiber glass tube or 1 inch I.D. PVC five feet long with bolts mounted
    from the inside used as terminals for the wires and coax feedline.

  • The center post is mounted to the baseplate with a square base floor flange normally used for
    handrails. This floor flange appears to be the same as is used in the commercial hex beam and can
    be found at numerous places on line. Search Google images using the term "handrail floor flange" to
    find sources.

  • Stainless steel hardware should be used to minimize corrosion. Lock washers should be used;
    otherwise movement of the hexbeam by wind and rotation will eventually work the fixtures loose.

  • You can save yourself the trouble and buy a base plate identical to this one with flange and U bolts
    from Ron, W4RDM who builds and sells them on his web site at www.hexkit.com.
12 X 12 inch 6061 T6 aluminum plate, 3/16 inch thick
This is 6061 aluminum plate
3/16 inch thick and 1 foot
square.
The plate can be cut with a
hacksaw by hand or by a
reciprocating saw with a metal
cutting blade. A piece of
board and clamp are used to
hold it all steady for cutting.
Measuring and marking the
hexagon.
A metal hole saw and a hand
operated drill can be used to
cut out the center hole.
The arrow will help you stay
oriented as you install the wires
later. Drill 5/16 inch holes to
attach the square floor flange
to the baseplate.
The vertical lines to mark the
terminal bolts should be 60
apart. The 60 degrees can be
marked from the lines on the
baseplate before the flange is
attached. The post should be
about 46-48 inches above the
baseplate with about 6-8
inches below.
Click these photos to enlarge
The baseplate and center post are
shown here on a temporary stand for
the remaining assembly of the
hexbeam.
When you stick the bolt down
inside the post with this wire,
push it through a terminal
hole, hold it in place with your
other hand and then push the
wire in further to disengage it
from the bolt. Put a nut on the
bolt it to hold it. This is a lot
easier than it would seem.
I did all five bands in less than
20 minutes. Put a split lock
washer, then a nut on each.
Hold the screw with needle
nose pliers while tightening the
nut.
Building the G3TXQ Broad Band Hex Beam
The holes for the U bolts are
carefully cut where the lines
have been measured.
Mark the center post for the
wire terminals based on the
measurements on the Position
of Wires Table on the
Specifications Page. The
measurements are above the
baseplate; not the top of the
flange.

Drill two holes for the driver
wires for each band on the 60
degree marks. You will be
using #10-24 X 3/4 bolts. The
bit size should be 3/16 inch.
The center post will fit snugly
through this floor flange. These
things are normally used for
hand rails and many
companies sell them. Just do a
google search for images using
the term, "base floor flange" or
some such words and you will
get a lot of vendors. Check
eBay; I found some on auction
there.
The finished baseplate with
the U bolts in place.
Use a piece of stiff wire (coat
hanger) with a loop as shown
to fish each bolt down the
inside of the center post. The
bolts are #10-24 X3/4 stainless
steel with a small lock washer
on each. The other nuts are
shown here and there will also
be a couple flat washers used
when the wires are attached.