Shrinkage, Skew and Directional Print Layout
An order for 30 table runners uses a 2.4 m length of 140 cm-wide cotton furnishing fabric with a large directional print, 3% warp shrinkage and 1% weft shrinkage. The worker has low vision and uses a one-handed rotary cutter with a guard, a cutting mat, and a clamped metal ruler. Pattern pieces are one centre panel 90 x 40 cm with grain along the length, two end panels 40 x 40 cm, and four napkins 45 x 45 cm. The supplier states a 32 cm print repeat and a 2 cm skew at one selvedge. An earlier layout without pre-shrinking required 2.55 m and put two end panels against the print direction. No extra fabric of the same dye lot is available. The worker can mark with contrast clips but cannot see fine chalk lines at 1 m. Decide whether to pre-shrink, calculate the usable size, and plan a layout and marking method that respects grain and print direction.
1. Calculate the fabric size after shrinkage and show whether all seven pieces fit with the grain and print direction.
Read the worked answer
Pre-shrink first. Without it, a 90 cm panel can finish about 3% shorter, or 87.3 cm, and the order will fail even if the layout fits. After shrinkage: length = 240 x 0.97 = 232.8 cm; width = 140 x 0.99 = 138.6 cm.
A workable layout uses 175 cm of the 232.8 cm length:
- First 90 cm: centre panel 90 x 40, plus three napkins in the remaining width. Place two napkins stacked in one 45 cm-wide column and one napkin in the next 45 cm-wide column. Width used = 40 + 45 + 45 = 130 cm, which fits 138.6 cm.
- Next 45 cm: fourth napkin, 45 x 45.
- Last 40 cm: two end panels side by side, 40 + 40 = 80 cm wide. Total length = 90 + 45 + 40 = 175 cm, leaving 57.8 cm. All seven pieces fit if every piece is aligned in the same print direction.
2. How would you place and mark the pattern for a low-vision worker while respecting the 32 cm print repeat and the 2 cm skew?
Read the worked answer
After pre-shrinking and pressing, square one end by cutting along the weft. Cut away the 2 cm skewed selvedge before measuring, and work from the centre of the fabric rather than the skewed edge. Use full-size templates with tactile notches at the grainline and seam allowance.
Align the centre panel to the print so the motif reads in one direction. Place the end panels and napkins in the same direction; do not rotate a napkin to save space. Check the 32 cm repeat at each seam so adjacent pieces match. For marking, use contrast clips every 10 cm along the grainline and at seam allowances; avoid fine chalk lines. Clamp the ruler and have a second person verify the first complete layout before any cut. Record the layout diagram and the measured usable length.
3. Give a safe cutting sequence for the one-handed rotary cutter and one check before each cut.
Read the worked answer
Clear the mat and place the fabric flat without stretching. Cut away the skewed edge first, then cut the longest straight edge to establish a true grain reference. Place templates and clamp the ruler so it cannot slip. Cut away from the body, keep the guard closed between cuts, and keep the supporting hand behind the ruler, never in the blade path.
Cut the large centre panel first, then the end panels, then the napkins. Cut no more than two layers at a time because the directional print and low vision make layer shifting hard to detect. Before each cut, check that the ruler is still on the marked line, the template has not moved, and the blade guard is working. Replace the blade when it drags rather than forcing the cut.