Nylon and polyester fray at a raw edge, but they melt — so a hot knife or a quick pass of a flame seals the edge as it cuts. Cotton fabrics like duvetyne don’t melt, so you bind, overlock or hem them instead.
Cutting
Use sharp fabric shears or a rotary cutter on a cutting mat. Mark with chalk or a fabric pen, not a ballpoint, and cut on a clean flat surface so the fabric doesn’t shift.
Sealing synthetic edges
- Hot knife — cuts and seals in one pass; the cleanest result for nylon and polyester.
- Flame — a quick pass of a lighter melts the edge. Keep the flame moving; you want to melt the fibers, not burn them.
- Fray check / seam sealer — a liquid option for edges you can’t reach with heat.
Work in a ventilated space and keep a safe, heat-proof surface underneath. Melted nylon is hot and sticky; let it set before handling.
Cotton is the exception
Cotton doesn’t melt, so heat-sealing does nothing for duvetyne or canvas. Bind the edge, overlock it, or hem it. See duvetyne vs commando cloth for stage fabrics.
Then sew
Leave yourself a seam allowance, and seal the edge before it goes under the presser foot so loose threads don’t jam the feed. Pair this with the right setup from sewing CORDURA at home.
Frequently asked
Will a sealed edge still fray after washing? A properly melted edge holds. If the item will be washed hard, combine sealing with a stitched or bound edge for durability.
Can I seal coated fabric? Yes — the coating melts with the nylon. Avoid holding the flame in one spot, which can scorch the coating.