A method of forming a tubular tapered composite pole for supporting utility lines comprising the steps of:
- a) forming a plurality of elongated rectangular blanks of pultruded composite material each having a height (H1) in the range of 30-120 feet, a left edge, a right edge, a top edge and a bottom edge;
- an interlocking structural groove is formed on both of said side edges of each blank substantially along their entire lengths during the time said blank was being formed by the pultrusion process;
- b) cutting at a biased angle from said bottom edge of each said rectangular blank to said top edge of each said rectangular blank to form a pair of panels each having a generally trapezoidal shape;
- said panels each having a left edge, a right edge, a top edge and a bottom edge;
- c) machining a tongue shaped interlocking structure substantially along the entire length of said biased angularly cut side edges of said panels;
- each of said panels having a length (L1) along said bottom edge in the range of 6″-24″ and a length (L2) along said top edge in the range of 3″-16″ and (L1) is greater than (L2) to give said panels a generally trapezoidal shape;
- said panels having a thickness (T1) in the range of 0.100-0.800 inches;
- and
- d) interlocking respective tongue and groove structure along the side edges of said panels to form a closed loop at their top and bottom edges and form a tubular tapered pole for supporting utility lines;
- said groove structure having been formed on said rectangular blanks during said pultrusion process and said groove structure has an outer jaw and an inner jaw each having inner surfaces configured to form a fir tree-shaped groove having at least first and second locking cavities;
- said tongue structure having been formed on a side edge of said panels after said rectangular blanks have been cut at a biased angle from said bottom edge of said blank to said top edge of said blank;
- said tongue structure having a fir tree-shaped cross section having an outer surface, an inner surface and an outer end;
- a head portion is formed on said outer end, spaced inwardly from said head portion is formed a first outer surface machined groove and a first inner surface machined groove;
- spaced inwardly from the respective first outer surface machined groove and said first inner surface machined groove are a second outer surface machined groove and a second inner surface machined groove;
- a double sided tooth portion is formed between said respective first and second machined grooves;
- said head portion snap locks into said second locking cavity and said double sided tooth portion snap locks into said first cavity to form a double snap lock mechanical joint;
- and said thickness of said tongue structure is no greater than (T1) at any point;
- and
- said vertically oriented primary panels arranged to form a closed loop at their top edges and their bottom edges such that said tongue structure on each panel is interlockingly engaged in said groove structure of said adjacent panel;
- said primary panels having been assembled together by snapping laterally said adjacent tongue and groove structure together;
- said primary panels having planar outer surfaces and planar inner surfaces in their pultruded formed state;
- when said primary panels are assembled together said outer surfaces and said inner surfaces of said primary panels remain in a planar state and are not subjected to stresses that would occur if they were bent in order to assemble adjacent panels together.