Shoulder Seam
The 11th Doctor’s velvet waistcoat was generally Victorian (or at least theatrical) in its style and cut, which is appropriate since it was perhaps primarily (or at least originally) intended to be worn with his “Snowmen” costume, which was comprised of a top hat, frock coat, and high-waisted trousers.
It also coordinated well with his subsequent, Victorian-style “7b” frock coat.
Upper Front
Like his “anniversary” waistcoat, the velvet waistcoat’s upper front opening wasn’t very deep; the center front closure extended quite high.
In fact, whenever the Doctor wore his scarf, it basically covered the entire upper front opening of the waistcoat.
Like his “anniversary” waistcoat, Eleven’s velvet waistcoat had a notch collar and lapels.
The “faux-collar” didn’t wrap around the back of the neck, but was instead sewn into the shoulder seam.
I never saw any evidence of a lapel/collar seam (“gorge line”), but that doesn’t mean there wasn’t one … the fabric was simply too dark for me to say for sure.
In lieu of any hard evidence, I say Occam’s Razor in this case.
It’s tough to say for sure based solely on screencaps and photos, but the lapels appeared to be cut-on (“grown-on”) and were simply rolled over.
Observe how the lower lapel appears to be more of a “roll line” than “fold line” or “seam line” (as opposed to the lapels on his “anniversary” waistcoat, which sat nice and flat).
Some of this was doubtless a result of the velvet waistcoat trim (which we’ll examine shortly), but the general drape of the lapels seems to be more of a gentle roll than a fold or seam.
The bottom of the lapel’s roll line appears to have been level with, or perhaps just above, the uppermost button.
Length
Fortunately, to determine the proper length of the velvet waistcoat, we have four separate visual references.
The first reference we have is the waist seam on the “Snowmen” frock coat.
Of course, different postures will result in different drapes, with natural resting stance being the ideal and any “poses” being less so (for our purposes).
The closest thing we have to natural resting posture was from this promotional photo for “The Time of the Doctor,” and the waist seam of the frock coat appears to indicate the natural waist being between the lowermost two buttons on the waistcoat.
The second reference we have is the waist seam on the 7b frock coat, which indicates a similar positioning, but a bit higher – level with, or perhaps just below the second-lowest button.
The third indicator of the original waistcoat length was in relation to his “Snowmen” trousers.
As you may recall, these were Victorian-style, high-waisted trousers, complete with a “double peak” in the back for the suspenders/braces.
Usually, the bottom of the velvet waistcoat slightly overlapped the top of the trousers.
Nevertheless, the two only overlapped marginally; when he moved and/or leaned, there was occasionally some “gappage” between the waistcoat and trousers.
The fourth (and final) visual reference we have regarding the velvet waistcoat length is in relation to the Doctor’s G-star jeans.
The lower front of the waistcoat appeared to be approximately level with the lower edge of the jeans’ waistband.
In fact, it could well be that the length of the velvet waistcoat was determined with the G-stars specifically in mind, so they’d just barely overlap in the front. (That’s just a theory, though.)
Conclusion?
The velvet waistcoat’s natural waistline appears to have been positioned approximately halfway between the two lowermost buttons, or as high as the level of the second-lowest button.
The waistcoat should extend just barely low enough in the front to overlap the G-stars, with the jeans’ waistband button peeking through at the bottom of the waistcoat.
The waistcoat should overlap the “Snowmen” trousers slightly more.
Lower Front
There were no darts on the lower front of the waistcoat.
At a glance, the velvet waistcoat appeared to have been flat across the lower front:
In actuality, though, the front of the waistcoat was slightly lower than the back, and it arced downward from the side seams toward the center front in a graceful curve.
Back
As you may have noticed, the back of Eleven’s velvet waistcoat wasn’t made of the same velvet as the front.
Alex Murphy (aka “The Ginger Doctor”) and Daniel Pawlik claim the costumer who made the original waistcoat(s) told them that the back of the waistcoat was purple linen – an interesting choice, since waistcoats are normally backed with silk, lining, etc.
Furthermore, the same linen was allegedly used on the back of both this and the “scales” waistcoat.
You can read his original blog post here:
https://thegingerdoctor.wordpress.com/2017/04/01/tipping-the-scales-eleventh-doctor-nirvana/
However, in the short prequel, “She Said, He Said,” we got a glimpse of the velvet waistcoat’s back fabric – the merest sliver of it visible between the shirt and frock coat collars – and it did, indeed, look quite purple.
Curiously, there sometimes appeared to be a band around the upper back of the neck …
This may have just been his tie or a shadow from either the tie and/or shirt collar, though, as other times there was clearly not an upper back neck band.
Of course, there were probably multiple production-made waistcoats; it’s possible one (or more) had the back neckband, and one (or more) did not.
The back neckline seam allowance appeared to be quite stiff – enough to make an impression.
Sometimes, there appeared to be a row of hand-stitching around the neckline – if so, then its purpose may have been to anchor the layers together, attach the lining, and/or control the seam allowances.
Then again, it may have been purely decorative.
As with the front, there were no lower back darts, either.
On the lower back of the waistcoat, there was a back strap to pull the wearing ease snugly (but comfortably) across the back.
The strap appears to have been made with the same fabric as the back of the waistcoat and trapezoidal in shape; it was widest at the side seam, narrowing toward the center back.
The buckle was attached to the back left, with the back right pulling through from the underside.
The strap was sewn into the waistcoat’s side seam, and the outermost several inches appear to have been stitched to the back of the waistcoat – either via topstitching (which is difficult to discern on linen), or invisibly hand-sewn.
Observe in the following photos how the strap suddenly starts to “dip” towards the center back a few inches from the side seam.
Also, the strap appears to have been positioned with its upper edge at about the same level as the outer corner of the lower pocket.