Extra fabric for one-way prints and nap depends on the layout

A one-way print or nap can rule out turning pieces upside down. The extra length depends on the shapes and the arrangements you compare; a universal percentage does not describe every pattern.

Use the pattern's with-nap requirement when one is provided, checking its width and variation. To compare layouts yourself, keep the pieces and width fixed and change only the direction rule.

Direction and matching are different constraints

A directional motif has an intended up and down. Nap can change appearance when the fabric faces the opposite way. Both affect which orientations you may use. Check the fabric itself and your sewing instructions before permitting a 180-degree turn.

Matching stripes or a large print across a seam also constrains position. Two pieces can face the same way yet meet at different points in the repeat. Seamwork explains this separate placement task in its guide to matching plaids, stripes and large patterns.

Compare candidate lengths, not claimed savings

For arithmetic only, imagine two complete layouts occupying 2.4 m and 3.0 m on the same width. The longer candidate uses (3.0 − 2.4) ÷ 2.4 = 25 percent more length. These numbers are illustrative; they are not recorded circle-skirt measurements or a standard nap allowance.

A restrictive direction rule removes possible orientations, but a heuristic search can return different-quality candidates in either run. The difference between two returned lengths is not proof of the minimum direction penalty. Inspect both layouts rather than treating the percentage as a fabric property.

Rectangles still need a direction check

A rectangle has the same outline after a half-turn, but its motif does not necessarily look the same. You may be able to keep the geometry of its placement while orienting it consistently. That observation does not remove repeat matching, grain or seam-position requirements.

What the app setting controls

PatternNest's one-way setting keeps a prepared piece in its current orientation. Grainline mode permits the current orientation and a 180-degree turn. It does not read printed grain arrows or detect the nap in your material. Prepare the imported outlines accordingly.

Repeat matching remains a cutting-table check. A shorter geometric plan cannot tell you where a particular stripe should meet at a side seam.

Check the layout in PatternNest

Import closed cutting outlines from SVG, DXF or a supported vector PDF and check their dimensions. Select individual PDF pages; tiled pages are not stitched automatically. For folded fabric, mark the cut-on-fold edge. Use a full unfolded outline when planning that piece on a single layer. Seam allowances are neither added nor removed; exported outer contours do not replace internal markings such as notches or grain arrows.

Orient the pieces according to your sewing pattern before import. Enter usable width, spacing, quantities and mirrored pairs. Grainline mode allows the prepared orientation and a 180-degree turn; one-way mode keeps the prepared orientation. The software does not test stretch or detect the fabric's actual direction.

The calculated length belongs to the returned layout. Check every placement, dimension and allowance before cutting. An incomplete search does not prove that no other arrangement fits. Repeat matching, shrinkage and defects still need a check on the cloth.

Calculation and PDF/SVG/DXF export are free for up to 10 fabric pieces, counting all copies and mirrored pieces. A mirrored pair counts as two. More than 10 fabric pieces require a license for both calculation and export.

Try your own pieces

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