UNDERSIDE OF COLLAR: "We lengthen the jacket’s collar so that we can turn back the ends. this hides the [contrasting] felt from view when the suit is worn. the collar points are secured with fine hand-stitching.'
The Great Coat Sew-Along: Shaping the Lapels and Collar: a tutorial from Paco Peralta
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I also reinforced the shoulder by adding bias cut hair canvas. Padstitched the lapels, taped the roll line (by hand) so that the lapels lie close to the body without gaping.