E-glass Yarn ECD 450-1/2: Two Twisted Strands Plied

Continuous glass filament is processed much like silk and rayon: strands are twisted, then two are plied together the other way. This is yarn ECD 450-1/2 from the US glass-yarn standard MIL-Y-1140H (1972): electrical-grade (alkali-free) glass, continuous filament, fibre about 0.00023 in thick, strands of 45,000 yards per pound, one strand twisted, two plied. It is the warp and filling of style 112 glass cloth for laminates (MIL-C-9084C). The picture: our diagram.