Razz-Ma-Tazz Quilt Block Pattern

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How to Sew the Razz-Ma-Tazz Quilt Block

The Razz-Ma-Tazz quilt block is built from half-square triangles, creating a bold and dynamic design. Here’s how to make it.

Materials:

• Fabric in at least two colors or prints
• Ruler & rotary cutter or fabric scissors
• Sewing machine
• Iron and ironing board

Instructions:

1. Cut two squares of fabric to the same size. For example, cut 5" squares for a 4" finished block.
2. Place the two squares right sides together with edges aligned.
3. Draw a diagonal line from one corner to the opposite corner on the wrong side of the lighter square.
4. Sew a ¼" seam on both sides of the marked line.
5. Cut along the marked line to separate the two half-square triangle units.
6. Press the seams open on each unit.
7. Trim the dog ears (small triangles that stick out beyond the seam) from each unit.
8. Arrange the HST units in the Razz-Ma-Tazz layout and sew together in rows, pressing seams in alternating directions.
9. Sew the rows together, matching seams. Press the final seams.
10. Trim the block to your desired finished size.
11. Repeat to create as many blocks as needed for your quilt.

Making Half-Square Triangles

This technique eliminates the need to directly manipulate the stretchy bias of the triangle. It uses two easy-to-cut squares to produce two half-square triangles.

On the back of the lighter fabric, draw a pencil line diagonally from corner to corner.

Stack a pair of light and dark squares right sides together. Sew a ¼" seam allowance on each side of the line.

You will end up with something like this:

Now cut along the diagonal line.

Press the seam to set it, then press toward the darkest fabric.

To trim to the exact size, line up the 45° diagonal on your ruler with the seam.

Then carefully trim your block with a rotary cutter.

How to Resize Quilt Blocks

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

Important: Always remove the seam allowance before doubling or tripling the size. For example, if your pattern calls for 3½" squares, subtract the seam allowances (½"), double the finished block size (3" → 6"), then add the seam allowance back (½"). You’ll end up cutting a 6½" piece of fabric.

Resizing Square Blocks

Add ½" to your desired 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 block that measures 3" × 4", cut a 6½" × 8½" rectangle of fabric.

Resizing Half-Square Triangle Blocks

Add ⅞" to the desired finished block size. For a 4" finished block, cut 4⅞" squares.

Resizing Quarter-Square Triangle Blocks

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