How to make a clasp purse (gamaguchi)

1. Materials & tools

Materials (a 10.5 cm clasp purse)

• Outer fabric — about 25 × 30 cm (10 × 12 in)
• Lining fabric — the same size
• Fusible interfacing — the same size
• Insert-type metal clasp (gamaguchi frame) — your chosen size
• Paper cord (often supplied with the clasp)
• Awl, plus craft glue or clasp-specific adhesive

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 “Bags” → “Clasp purse” from the tabs at the top.
2. Enter the size
   Enter your clasp's outer width and height plus the purse depth; the fabric width is auto-calculated as clasp width × 1.6. Turn on the rounded-corner option to match the clasp curve.
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 onto the wrong side of the fabric. Fuse interfacing to the outer so it sits firmly in the clasp.
2. Cut the pieces
   Cut 2 outer and 2 lining. The dashed line at the top edge of the pattern is the clasp position.
3. Check against the clasp
   Before sewing, hold the actual clasp against the top edge to confirm the width and curve match — this avoids surprises later.

4. Sewing

4-1. Sew the bags

1. Place the 2 outer pieces right sides together and sew the sides and bottom below the clasp line (dashed). Leave the part above the line unsewn.
2. Sew the lining the same way, leaving a turning gap on one side.
3. For a flat base, pinch each bottom corner into a triangle and sew across.

4-2. Join outer and lining

1. Turn the outer right side out and slip it inside the lining (still wrong side out), right sides together.
2. Sew around the curved opening where the clasp will attach.
3. Turn everything right side out through the gap in the lining, close the gap, and shape the opening.

4-3. Fit the clasp

1. Run craft glue (or clasp adhesive) into the channel of the metal frame.
2. Push the fabric edge into the channel with an awl, working from the centre out to each end so it stays even.
3. Press paper cord into the channel alongside the fabric to lock it in place.
4. With a scrap of cloth protecting the metal, gently squeeze the clasp ends with pliers. Let it dry and you are done.

5. Tips & variations

• Plumper body: interface both outer and lining for a rounder, firmer purse.
• Clasp won't fit: the fabric edge may be too thick — use lighter interfacing or thinner paper cord.
• First clasp: an insert-type frame around 10.5 cm is the easiest to learn on.