Why Seam Finishing Matters
Unfinished seam allowances fray with wear and washing — the threads gradually work loose, creating a progressively messier interior that eventually affects the garment's structural integrity. Beyond durability, the inside of a garment is visible to judges in masquerade craftsmanship judging. Professional seam finishing is a mark of quality that distinguishes serious cosplay construction from amateur work.
Serged Seam Allowances
Overlocking (serging) the raw edge of each seam allowance is the fastest and most common finishing method. A serger stitches and trims simultaneously, creating a clean finished edge that will not fray. Serge each piece's cut edges before assembling where possible (before assembly serging) or serge the seam allowances together after stitching (after assembly serging). The former provides cleaner results on most garments.
French Seams
A French seam encloses the raw edges within the seam itself — no raw edge is exposed. This is achieved by sewing the seam with the wrong sides together first, trimming close, then folding so right sides are together and stitching again, enclosing the first seam inside the second. French seams are appropriate for light to medium fabrics and curved seams with gentle curves; they add bulk and are inappropriate for heavy fabrics or tight curves.
Hong Kong Seam Finish
The Hong Kong finish uses bias tape to bind each raw seam allowance individually before or after assembly. It's time-intensive but produces the cleanest possible interior finish — the standard for couture construction and high-end masquerade entries. Matching the bias tape colour to the fashion fabric creates an interior that looks as intentional as the exterior.