How to make a collarless jacket

1. Materials & tools

Materials (women's M)

• Main fabric (tweed, linen or heavy cotton) — about 110 cm wide × 200 cm (44 × 79 in)
• Lightweight fusible interfacing — about 30 cm (12 in) for the front facings
• Optional: a covered button or snap
• Optional: lining fabric

Tools

• Sewing machine (or needle and thread)
• Fabric marker or pencil
• Ruler and scissors
• Iron
• Pins or clips

2. Make the pattern (auto-generated in Katagami)

With the Katagami pattern tool, you just enter the finished size and it drafts a seam-allowance-included pattern, tiled to print at actual size on Letter or A4.

1. Open the tool
   Open the pattern tool and choose “Adult clothes” → “Collarless jacket” from the tabs at the top.
2. Enter the size
   Enter bust, length, shoulder width, sleeve length and ease. Presets cover women's S/M and a relaxed fit.
3. Set the seam allowance
   Use the slider at the bottom (beginners: 1.0–1.5 cm / about 3/8–5/8 in).
4. Print
   Press “Print (actual size)”, then in the print dialog set Scale = 100% and turn “Fit to page” OFF. Check the 50 mm calibration box on the first guide sheet with a ruler.

3. Cutting the fabric

1. Trace the pattern
   Trace the back (on the fold), the fronts, the sleeves and the front facings.
2. Cut
   Cut one back, two fronts, two sleeves and two facings.
3. Apply interfacing
   Fuse interfacing to the facings. That is what makes the front edge sit crisply instead of rolling.
4. Finish the edges
   Zigzag or serge the shoulder, side and underarm allowances.

4. Sewing

4-1. Sew the shoulders

1. Sew both shoulder seams and press the allowances open.

4-2. Attach the facings

1. Join the facings at the shoulders if your version continues around the back neck.
2. Pin a facing to each front, right sides together, and sew in one run up the front edge and around the neckline.
3. Clip the neckline curve every 5 mm (¼ in). Skip this and the neckline will pull no matter how carefully you sewed it.
4. Turn the facing to the inside, press hard, and understitch 2–3 mm from the edge so it stays rolled in.

4-3. Attach the sleeves

1. Match the center of each sleeve head to the shoulder seam and sew the sleeve in.
2. Spread the sleeve-head ease across roughly 15 cm (6 in) either side of the top. Bunched in one place it becomes a tuck.

4-4. Sides and underarms

1. Sew from the cuff along the underarm and down to the hem in one line, matching the underarm seams.

4-5. Cuffs and hem

1. Turn the cuffs under twice and stitch.
2. Hem the lower edge. At the facings, fold the hem with the facing opened out, then fold the facing back and slipstitch.
3. Add a snap or covered button at chest height if you want it to fasten.

✏️ Do not be shy about clipping the neckline. Curved seam allowances always pull unless they are clipped, up to 1–2 mm short of the stitching, every 5 mm. Kept that shallow they will not fray.

5. Tips & variations

• Interface the facings only: interfacing the whole jacket makes it board-stiff. The front edge and neckline are all that need to hold their shape.
• No fastening needed: collarless jackets are usually worn open. Leaving off the button looks entirely deliberate.
• Adding a lining: cut the same pattern in lining and join it to the inner edge of the facings. It slides on far more easily.