How to make a key case

1. Materials & tools

Materials (one case)

• Main fabric (canvas, faux leather or heavy cotton) — about 25 × 20 cm (10 × 8 in)
• Lining fabric — the same amount
• Firm fusible interfacing — the same as the main fabric
• Key case hardware (a 6-hook key ring plate) — 1
• Snap fastener — 1 set

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 “Accessories” → “Key case” from the tabs at the top.
2. Enter the size
   Enter the finished width, height and closure tab extension. Presets cover small, standard and large.
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 body and mark the center fold line.
2. Cut
   Cut one main and one lining.
3. Apply interfacing
   Fuse firm interfacing to the main fabric — a key case needs body to hold its shape.

4. Sewing

4-1. Sew the layers together

1. Place main and lining right sides together and sew around, leaving a 6 cm (2½ in) gap.
2. Clip the curve on a rounded tab, or trim the corners diagonally on a square one.

4-2. Turn and topstitch

1. Turn through the gap, ease the corners out and press.
2. Topstitch 3 mm from the edge all the way around, closing the gap. Slow the machine down — it is thick.

4-3. Attach the hardware

1. Position the key plate on the center fold line.
2. Stitch it on by hand through its mounting holes. The machine cannot reach past the metal, so this part is hand sewing.
3. Use doubled heavy thread and go back and forth four or five times per hole — the weight of the keys hangs here permanently.

4-4. Add the snap

1. Fold at the center and check where the tab reaches.
2. Fit the snap, allowing for the thickness of the keys inside.

✏️ Hand-stitching the hardware is the one step people rush, and it is the one that fails. Doubled thread, four or five passes per hole, and hide the knots between the layers if you can.

5. Tips & variations

• Faux leather needs no interfacing: it has body of its own. But every needle hole is permanent, so sew it once.
• Add a D-ring: caught in the side seam, it takes a strap or a carabiner.
• Contrast lining: a different fabric inside is a small pleasure every time it opens.