Tools · Trimmings
How much cord, how wide to cut, how much fabric — straight or bias — with the joins counted.
Step 1 — how much piping? Enter a length, or let the cushion counter add it up.
orStep 2 — the fabric.
Bias-cut strips stretch, so they lie flat around curves — scroll arms, round stools, serpentine fronts. That flexibility costs fabric: cutting at 45° wastes the triangular ends and needs more joins. On the dead-straight seams of a box cushion or a squared seat, straight-cut strips on plain cloth are what the trade actually uses; the piping cannot pucker on a straight run. Patterned cloth is the exception — straight-cut strips show the pattern running along the piping, which can look wrong; bias breaks the pattern up. Strip widths here give a 12–15 mm flange beyond the cord for the machine foot to run against.
For standard upholstery cord: 4 cm strips for 4-5 mm cord, 4.5 cm for 5-6 mm, 5 cm for 6 mm, and 6 cm for 8 mm chunky cord. That gives enough to wrap the cord with a 12-15 mm flange for the machine foot.
Only where the piping has to follow curves - bias-cut strips bend without puckering. On the straight runs of box cushions and squared seats, straight-cut strips on plain fabric are standard trade practice and waste far less cloth.
Straight cut from 140 cm fabric at 4 cm strips: about 0.35 m of fabric makes 10 m of piping. Bias cut needs roughly 0.45-0.5 m for the same length because of the diagonal waste. The calculator gives exact figures for any length, cord size and fabric width.