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Seam lines shown. The colors show which fabric goes where. You pick the fabrics on the Design Wall.

Half-square triangles

Dutch Pinwheel

A pinwheel of broad feature blades, each blade tipped with a half-square triangle so the whole block appears to spin. Built from four identical quarters rotated a quarter turn each.

Cut list

What to cut for one 12 inch finished block. A quarter inch seam allowance is already in every size.

Feature

2 squares
3⅞"Cut once on the diagonal, layered with the background fabric. Each square makes 2 triangles.
12 squares
3½"

Background

2 squares
3⅞"Cut once on the diagonal, layered with the feature fabric. Each square makes 2 triangles.
By region
Every region of the Dutch Pinwheel block, the units it needs, and what they are cut from
RegionUnitsCut from
Feature 113½"
Feature 213⅞" square, cut once on the diagonal
Background 113⅞" square, cut once on the diagonal
Feature 313½"
Feature 413½"
Feature 513½"
Feature 613⅞" square, cut once on the diagonal
Background 213⅞" square, cut once on the diagonal
Feature 713½"
Feature 813½"
Feature 913½"
Feature 1013⅞" square, cut once on the diagonal
Background 313⅞" square, cut once on the diagonal
Feature 1113½"
Feature 1213½"
Feature 1313½"
Feature 1413⅞" square, cut once on the diagonal
Background 413⅞" square, cut once on the diagonal
Feature 1513½"
Feature 1613½"

How it goes together

  1. Step 1

    Cut your pieces

    Cut the pieces in the cut list. The sizes are for a 12 inch finished Dutch Pinwheel block and already include a quarter inch seam allowance.

  2. Step 2

    Make the half-square triangle units

    Sew each pair of triangles along its long edge and press toward the darker fabric. Trim every unit to size before you join it.

  3. Step 3

    Assemble the block

    Join the units into rows, then join the rows. Press as you go and square the finished block to size.

Try the Dutch Pinwheel on a real layout.

Open it on the Design Wall. Try a few colors, see the math, change your mind.