Interfacing Types
Interfacing comes in fusible (iron-on) and sew-in versions, and in multiple weights from very lightweight (for delicate fabrics) to very stiff (for waistbands and collars). Match the interfacing weight to the fabric weight and the amount of body needed. A rule of thumb: the interfaced piece should feel more structured than the uninterfaced fabric without feeling stiff or plastic.
When to Interface
Interface: bodice fronts on fitted garments; collar stands; waistbands; cuffs; the facing on any facing-finished edge; any area that needs to hold a specific shape. Do not interface: garments that need to move and drape freely; lining fabrics (unless specifically for structure in that area); stretch fabrics that need to retain their stretch.
Boning for Costume Structure
Boning in a bodice prevents it from folding or collapsing under the pressure of wearing. Spiral steel boning for curved seams; flat steel for side seams and front panels; rigilene (polyester boning) for less structured applications where the full rigidity of steel isn't needed. Sew boning into channels on the inside of the bodice — channels sewn from the interlining or lining fabric, positioned on or near the vertical seam lines.