Analysis, part 6 - Trim and Body Seam Allowances

Although the jumpsuit body was unlined, the yoke was (O'Brien's uniform in "Strange Bedfellows" notwithstanding). 

The lining seems to have varied over the years and, although the yoke seems to have simply been lined with the same black wool gabardine as the body, it was probably lined sometimes with what they had just lying around, as evidenced by the gray herringbone yoke lining on Nog's uniform:

In addition to the lining in the above photo, we have identified three other key pieces of information: 

1 - As with the VOY jumpsuit, the back body seam allowance was quite large - at least ⅞", probably 1". (We use 1" seam allowance on our pattern.)

2 - As with the VOY jumpsuit, the back body seam allowance was pressed upward, although on the DS9/NEM jumpsuit, the seam allowance was secured via a "stitch in the ditch" along the upper edge of the back yoke trim. 

3 - The free end of the back seam allowance was hand sewn to the yoke lining. 

DS9, 7x19 "Strange Bedfellows"

Although O'Brien's yoke appeared to be unlined (or lined with fabric of a lighter color), the front appeared to have large body seam allowances, as well, and was likely secured in the same manner as the back: 

Although the inside of the yoke would probably never be seen on screen, the yoke was probably lined purely for cosmetic reasons; the body seam allowances could be hand sewn to the backing of the quilted yoke, as could the front zipper facing and shoulder pads.

Still, though, either quilting the yoke with black backing or lining it in black was a better, safer choice, albeit a bit more time-consuming. 

Nemesis

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