Authored stardate 1810.25 by 
For Starfleet officers serving the Terran Empire of the Mirror Universe, a gold sash is the crowning uniform accessory, alongside their ever-present dagger.
This article will expound upon the various sash styles seen in the STAR TREK: The Original Series episode “Mirror, Mirror” [2x10], and provide a practical tutorial for their replication.
N.B.- The author's "Mirror Universe Captain Kirk" replica achieved a finalist slot in the 2018 costume contest at Star Trek Las Vegas; an article on "Mirror Kirk's Waistcoat" is planned to follow!
Protocol and Design
Sashes are one designator of commissioned officers ranked Ensign and above. They are not worn by enlisted men (who do not even exist onboard the Prime Universe Enterprise at this point in time, as further examined in Ratings and Enlisted Men).
In exception to this are the redshirt ship's security officers (of all ranks).
Presumably for practical reasons, they forego both the sash and dagger — instead wearing phasers and agonisers on black weapons belts, akin to non-commissioned bodyguards.
N.B.- There is one clear continuity error discarded from this analysis, but mentioned here for completeness. Mirror Chekov wears the same sash and dagger as other officers – including when entering and exiting the turbo-elevator with Kirk – but these "magically transform" into a weapons belt inside the turbo-elevator itself. (Conclusion: someone supplied Walter Koenig with the wrong wardrobe items on the day the elevator interior scene was filmed.)
Sash Styles
All observed sashes fall cleanly into 3 categories based upon gender and rank...
- Male Officers -
- "Standard-length" sash with angle-cut ends and no fringes, typically worn draped to the mid-thigh.
- Male* Captain -
- "Longer-length" sash with angle-cut ends and gold fringes, worn draped to the lower thigh.
- Female Officers -
- "Shorter-length" sash with straight-cut ends and gold fringes, worn with approximately one foot (~1') of drape below the knot.
*N.B.- A Female Captain is herein theorised to also wear a "longer-length" sash with gold fringes (as per her male counterparts), but having the same straight-cut ends as the other women's sashes. That design feature firmly establishes itself within the episode as an entirely gender-specific fashion choice unrelated to rank.
Sash Placement
All officers wear their sashes tied around the waist and knotted towards the left — with the sole exception of Captain Kirk, who wears his tied towards the right.
The Captain's sash has a unique design, but it is nonetheless unknown whether Kirk's knot placement is due to his rank, or a consequence of his choice of uniform.
The Mirror Universe waistcoat is clearly an alternative uniform variant analogous to the Prime Universe wraparound, upon which placement of details such as Breast Insignia and Officer Rank Insignia have varied from the norm.
It is therefore debatable on which side a Mirror Universe Captain would tie his sash when donning a command gold service uniform. The author would argue for standard left-side placement: STAR TREK as a series establishes a precedent that the captain's insignia is always placed according to his uniform style.
Sash Width
The majority of sashes in “Mirror, Mirror” [2x10] were likely made identical in width, despite the appearance of variety throughout the episode.
As it would make no good sense to cut many strips of fabric to random widths, the variances can be explained as an optical illusion created by the fabric contracting in width as it is stretched in length.
In effect, the tighter a sash is stretched around the waist, the narrower the tied portion has the tendency to become.
This can be seen by comparing the actual width of a sash at its loose ends, to how narrow it (sometimes) appears to be around the waist:
It is estimated that the typical sash was a cut of fabric approximately six inches (~6") wide, with half an inch (½") turned over as hem allowance on all edges.
Scotty's sash objectively appears to be slightly wider and longer than the standard, and was perhaps a seven inch (7") cut. This may have been done to compensate stylistically if James Doohan had a larger waist size than the other actors.
N.B.- Width estimates were arrived at via thorough study of photos and screencaps; however, a verification measurement from anyone possessing a screen-used item would be welcomed!
Fabric and Trim
Modern photos of screen-used sashes indicate that they were constructed of a loose, stretchy mesh featuring a brightly-reflective and highly-textured gold metallic side.
As an indicator of weave, nearby light sources could easily be seen through the mesh when backlit on display, despite that it appeared deceptively dense on-screen.
Unfortunately, there is currently no known source for the original fabric.
One substitute that is widely used by the fan community is gold sparkle tinsel:
Also variously described as lurex sponge or metallic bouclé, this family of polyester/lurex material is highly available from various merchants on eBay, Etsy, and independent websites.
Albeit not having the correct weave, it provides a worthy simulation of the original fabric's effect — which itself could be seen with a stray piece of "tinsel" sticking out from time to time!
Fabric should be sought in full 55 to 60 inch width, allowing complete sashes for the widest possible range of waist sizes to be made from single straight cuts.
Additionally – as multiple factories create similar fabric – surface texturing, tinsel shade, and base polyester colour can all vary somewhat between manufacturers and runs. An older, more "antique" gold is preferable to a bright yellow gold, but either can be sufficient (especially considering it is often difficult to accurately discern the exact gold colour from online photos).
One can reasonably expect a yield of 3 to 6 sashes per metre. Due to the variances, Mirror Universe fan productions and cosplay groups are strongly advised to stock several metres in reserve, to ensure consistency across uniforms.
Gold Fringe
UPDATED for January 2019: the author has obtained photos of sufficient resolution to determine that one of the original sashes worn by William Shatner was trimmed specifically with metal bullion fringe:
This type of trim was also utilised on the shoulders of Captain Kirk's Mirror Universe Waistcoat. It is an interesting wardrobe choice for something as "free-swinging" as a sash, since the strands are virtually impossible to repair if they become bent out of shape.
Due to the fragility and cost of metal bullion, which can also be somewhat rare, Mirror Universe costume replica sashes often utilise chainette fringe in a "metallic" gold, which is widely available. Gold "metallic" bullion fringe can also be substituted, provided it is the finer variety with strands no more than approximately 1⁄8" thick (most are far too coarse).
By the definitions employed herein, chainette fringe is a "medium-density" fringe — its strands are thinner than the twisted cords of bullion fringe, but thicker than those in brush fringe (which are wispy and easily become untamed):
N.B.- The chainette fringe is pictured here with its factory pull cord; this should be retained until fully sewn into a sash.
Adhering to the Protocol and Design section above, fringe is present on the sashes worn by Kirk, Uhura, and Marlena Moreau.
There are slight variations in length; this might be accounted for simply by differences in how far the top of the fringe was turned to the under-side during construction, or else the studio may not have had enough yardage of any one specific length onhand.
It can thus be said that standard fringe length for Mirror Universe uniform work is two to two-and-a-half inches (2 - 2 ½"). Given the observable details, a replica of Marlena Moreau's should certainly aim towards the upper number for character-specific screen accuracy.
Sash Construction
In most costuming practice, sashes are constructed double-layer: two strips of fabric are placed right sides together, then sewn around their edges and turned inside-out, producing a sash that has the "right side" of the fabric on both sides.
Contrary to this, every sash in “Mirror, Mirror” [2x10] for which the author has been able to conclusively verify construction was made single-layer.
A single-layer sash (as the name implies) is instead constructed from a single layer of fabric that has been finished simply by having its edges turned under and hemmed.
Aside from economising on material, these thinner and lighter sashes may be easier to tie, and the loose ends may "billow" to superior effect — but care must be taken to ensure that they do not twist or curl over, otherwise the wrong side of the fabric will be visible.
Kirk, McCoy, Scotty, Uhura, and Chekov are all confirmed to have worn single-layer sashes, with the wrong sides revealed in the following screencaps:
Sulu's is just barely revealed as he approaches the Communications station at 0:09:43, and Marlena Moreau's is at 0:28:57 when she passes through the door within Kirk's quarters.
For further study: the greatest frequency of "wrong side reveals" in “Mirror, Mirror” [2x10] occurs during the sickbay fight, beginning with a grand reveal of the reverse side of William Shatner's sash at 0:38:21 when Kirk first turns to attack Mirror Spock (whose sash is also finally revealed to be single-sided in the chaos that ensues). Stepping through this scene frame-by-frame on the HD Remastered (1080p) Blu-ray is encouraged.
Construction Process
The author's tutorial for sash construction follows.
Disclaimer: This process is intended to efficiently produce replica sashes from the modern gold lurex tinsel fabric described above. Without the original fabric being available, particular moot points are in which direction it stretched, and on what grain or angle sashes on TOS may have actually been cut.
- Ensure that the end of the yardage is cut as straight as possible (i.e.- perfectly down the cross-wise grain, perpendicular to the selvage edges). If equal care is taken to cut each subsequent sash straight, the fabric should only need to be "trued" once.
- Fold the fabric in half lengthwise (selvage edges together) with the right side on the inside.
- Cut a strip six inches (6") wide off the end of the yardage (down the cross-wise grain), which will produce a sash with the greatest amount of horizontal stretch. Alternatively – given how much the fabric has a tendency to contract – a seven inch (7") strip can be cut if there is a particular interest in having the sash retain a wider appearance around the waist. A guideline can be drawn on the wrong side to assist straight cutting.
- Test the length of the strip against the waist size of the intended wearer, keeping in mind that it will stretch well beyond its cut size. For extra-large sizes, or if the fabric is not full 55 to 60" width, two strips may need to be joined with a simple seam (although doing so might be considered a "hack", since no multi-piece sashes have been identified on TOS). Assuming enough yardage, an alternative to the seam is to cut the sash in one continuous piece on a diagonal angle to the grain-line, although the material waste in doing so is excessive.
- If the fabric has curled during cutting, use an iron on the wrong side to gently press it flat. Be wary of using high heat, as the fibres can melt.
- Turn each of the long edges under to the wrong side half an inch (½") and sew down, with the following tips given:
- A ball-point needle will help avoid shredding the tinsel.
- A zig-zag stitch will help avoid broken stitching when the sash is stretched.
- A roller foot (or a walking foot) will ease the passage of the material through the machine.
- Gutermann 865 is the author's standard gold thread for TOS sashes and braid.
- Tie the sash around the waist as it will actually be worn. If necessary, mark and cut it down to the desired length, plus one inch (1") for two hems. (This step is being performed after sewing down the edges, which can permanently stretch out the fabric to a longer length than it maintained prior to hemming.)
- Only if constructing a male officer's sash, cut the ends on 45° angles — otherwise skip to the next step. The correct configuration of the angle cuts is shown in the photo below.
- Only if constructing a female officer's sash or a captain's sash, now add gold fringe to each end by placing the fringe atop the right side of the fabric, aligning the top of the fringe with the end of the sash, and sewing it down with a line of straight stitching.
- Turn under a half-inch (½") hem to the wrong side at each end of the sash, and sew it down. (If fringe was attached in the previous step, the top of the fringe turns under with the hem allowance.)
Congratulations — your Mirror Universe Sash is complete!
Shown in the above photo is a straight six-inch (6") cut of sixty-inch (60") wide sparkle tinsel fabric, versus the author's prototype (2018) Mirror Captain's sash made from the same. The latter features two-inch (2") gold chainette fringe, and has further narrowed in width as well as elongated to over seventy inches (70") after two days of convention wear as Mirror Kirk!
Acknowledgements
- Star Trek: TOS screencaps from TrekCore.
- Photos of screen-used originals and other material at Star Trek Prop, Costume & Auction Authority.