The boom that I made consist of five 4’ sections of square fiberglass.  3 sections are 1 1/4” and 2 sections of 1 1/2”.  In the units I make up now I use 3 sections are 1” and 2 sections of 1 1/4”.  Mark one of the smaller section at the 2’ mark (middle) and slide it into one of the larger section.  Use 1 or 2 pop rivet (3/16”) to secure the boom together.  Now slide the other larger section on and butt it up to the other larger section and secure it.  The last two smaller sections, draw a line at 12”and slide it into the larger section and secure it.  Your boom should be 14’ long.  Mark the boom as to where the driven, reflector, and driven elements are to go.  On the heavy duty antenna I remove a 1” square from the boom where the driven and reflector will go.  On the standard model I remove the material from the element support and slide the support onto the boom.  Drill 1/8” hole where D1 through D6 will be placed.