Method of assembly of tubular metallic fences

A method of assembly of components of a tubular metallic picket fence, comprising the steps of:

• (a) furnishing, at an interior work site of a horizontal metallic tubular constructional element of the picket fence to be assembled, at least one internal structure having a defined female geometry spaced from the interior walls of said tubular constructional element;
• (b) providing, through said horizontal constructional element, a vertical opening proximal to said defined internal structure, to enable passage therethrough of a vertical tubular constructional element;
• (c) positioning said vertical tubular constructional element within said vertical opening of said horizontal element so that at least one surface of said vertical element is proximal to said defined internal structure of said horizontal element;
• (d) providing, within said vertical tubular element, at said one surface of said vertical constructional element, a distal portion of a highly extended longitudinal member of substantially uniform cross-section having a smaller external diameter than the internal diameter of said vertical tubular element, said distal portion comprising at least one working surface transversely extensible in reaction to longitudinal extension of said extended member;
• and
• (e) providing and applying, through said extended longitudinal member, selectable powered longitudinal thrust of said extended member, sufficient to provide to said working surface of said distal portion of said extended member, a transverse force sufficient to deform said one surface of said vertical tubular constructional element into said defined female geometry of said internal structure of said horizontal tubular element, thereby effecting the securement of said vertical and horizontal constructional elements to each other.