Slanted Diamonds And Streak Of Lightening Strips Quilt Block Pattern

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How to Sew Slanted Diamonds & Streak of Lightning Strips Quilt Blocks

Here are step-by-step instructions on how to cut and sew together slanted diamonds and streak of lightning strips quilt blocks.

Materials You'll Need

• Fabric in desired colors for diamonds and lightning strips
• Rotary cutter
• Quilting ruler
• Cutting mat
• Sewing machine
• Thread
• Iron
• Pins

Step 1: Cutting the Diamonds

1. Choose your desired fabric for the diamonds. You can use a single fabric or a variety of fabrics for a scrappy look.
2. Cut strips of fabric that are 1.5 times the width of the finished diamond block. For example, for a 4" finished diamond, cut 6" wide strips.
3. Cut the strips into squares matching the desired finished diamond width (e.g., 4" × 4" squares).
4. Place a square on your cutting mat with one corner facing up. Align your quilting ruler diagonally from corner to corner.
5. Cut along the diagonal line with your rotary cutter to create two triangles — the two halves of your diamond block.

Step 2: Cutting the Lightning Strips

1. Choose your fabric for the lightning strips — this creates the slanted lines in your quilt block.
2. Cut strips the same width as your diamond squares (e.g., 4" wide).
3. Cut the strips into rectangles twice as long as the finished diamond width (e.g., 4" × 8" rectangles).

Step 3: Sewing the Diamond Block

1. Place one triangle right sides together with one end of a lightning strip rectangle. Align the edges and pin in place.
2. Sew along the pinned edge with a ¼" seam allowance, starting from the triangle point and sewing toward the base.
3. Press the seam toward the triangle.
4. Place the second triangle right sides together with the other end of the rectangle. Align, pin, and sew with a ¼" seam allowance from the base toward the point.
5. Press the seam toward the triangle.
6. Trim the excess fabric from the triangle points so all edges are even.

Step 4: Assembling the Quilt Block

1. Place a lightning strip rectangle right sides together with one side of the diamond block. Align, pin, and sew with a ¼" seam allowance from the triangle base to the top edge.
2. Press the seam toward the rectangle.
3. Repeat with another rectangle on the remaining side of the diamond block.
4. Press the seam toward the rectangle.
5. Trim the block so it is square with all edges even.
6. Repeat all steps to create as many blocks as needed for your quilt.

How to Resize Quilt Blocks

The first step in modifying any quilt block is to decide on your finished block size. You can base this on doubling a pattern, cutting it in half, or working with your available fabric.

Note: When working from a pattern's cutting instructions, remove the seam allowance before scaling. For example, if your pattern calls for 3½" squares, subtract the seam allowance (½"), double the finished size (3" → 6"), then add the seam allowance back (½") — giving you a 6½" cut piece.

Resizing Square Blocks

Add ½" to your finished block measurement. For a 4" finished square, cut a 4½" square of fabric.

Resizing Rectangular Blocks

Add ½" to both the length and width. To double a 3" × 4" block, cut a 6½" × 8½" rectangle.

Resizing Half-Square Triangle Blocks

Add 7/8" to the desired finished block size. For a 4" finished HST block, cut 4⅞" squares.

Resizing Quarter Square Triangle Blocks

Add 1¼" to the desired finished block size. For a 4" finished block, cut 5¼" squares.