Installation fin for windows and doors

A method of producing a fenestration installation fin comprising the steps of:

• (a) placing an elongated, thin, fin body into contact with a knurling wheel, said body presenting a pair of opposed faces and a pair of elongated, opposed, spaced apart, inner and outer side margins, said inner margins including structure for attachment to a fenestration product;
• (b) using said knurling wheel, forming in said body an elongated fold line generally parallel with and proximal to said inner side margin for permitting selective pivotal movement of an outer section of said fin body about said fold line,
• step (b) including the step of forming said fold line by producing a plurality of elongated, aligned depressions in at least one face of said body, forming said depressions so that the long axes thereof present an oblique angle relative to the longitudinal axis of said body thereby cooperatively forming said fold line and so that said depressions are discreet and axially spaced from each other, and forming said depressions so that the spacing therebetween and the depth thereof cooperatively define a line of weakness along said fold line.