How to make a school satchel cover

1. Materials & tools

Materials (standard size)

• Main fabric (water-repellent fabric, laminate or nylon) — about 40 × 45 cm (16 × 18 in)
• Wide bias tape — about 120 cm (47 in)
• Reflective tape — about 25 cm (10 in)
• Narrow flat elastic (0.6 cm / ¼ in) — about 40 cm (16 in)
• Optional: clear vinyl (about 0.3 mm)

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” → “School satchel cover” from the tabs at the top.
2. Enter the size
   Enter the flap width, length, lower corner radius and ease. Presets cover standard, large and a version for a clear cover.
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. Measure the satchel
   Measure the flap width and its length from the hinge to the tip, and note the radius of the rounded end.
2. Trace the pattern
   Trace the body. The marks show suggested elastic positions.
3. Cut
   Cut one body. Use clips rather than pins — laminate keeps every hole.
4. Finish the edges
   Not needed; the edges are bound.

4. Sewing

4-1. Attach the reflective tape

1. Lay the tape along the curve at the lower end, on the right side, and stitch both long edges.
2. Change direction gradually to follow the curve.
3. Do this first — once the edge is bound, the tape ends have nowhere to hide.

4-2. Bind the edges

1. Bind all the way around with wide bias tape, which follows the curve naturally.
2. If you double-fold instead, ease the outer edge in around the curve.
3. Laminate sticks to the presser foot: use a Teflon foot, or lay tissue paper on top and tear it away.

4-3. Attach the elastic

1. Sew elastic loops at the center of the lower edge and at the marked points on each side.
2. The lower loop hooks over the satchel's clasp; the side loops go over the strap fittings.
3. Fit the cover to the satchel and check the positions before sewing them permanently. Too loose and it falls off; too tight and the flap will not close.

4-4. Finish the top edge

1. Either add two self-fabric loops that hook over the satchel hardware, or leave the top edge to tuck under the fitting.
2. For a version that holds a road-safety card, make the top edge into a pocket the card slides into.

✏️ Laminate and coated fabric keep every needle hole. You cannot unpick and try again, so fit the cover to the actual satchel and mark the elastic positions before you sew anything down. Clips, not pins.

5. Tips & variations

• Reflective tape earns its place: it costs very little and transforms visibility on a dark walk. Do not leave it off.
• Water-repellent fabric only: the whole purpose is rain, and ordinary cotton simply soaks through.
• Make two: it gets splashed with mud constantly.