Snail's Trail Quilt Block Pattern

New to quilting? Click here for a beginner in-depth sewing class covering all the basics.

How to Sew a Snail's Trail Quilt Block

The Snail’s Trail is a popular and classic quilting pattern that creates a beautiful interlocking spiral design. It’s a stunning block that really shines with two high-contrast fabrics.

Materials:

• Fabric squares in two contrasting colors
• Sewing machine & thread
• Rotary cutter, cutting mat & ruler
• Iron

Instructions:

1. Cut 4½" squares — you will need 16 squares in each color.
2. Cut each 4½" square diagonally in half to create 32 triangles of each color.
3. Arrange the triangles into 16 squares, alternating colors in a clockwise direction to create the snail’s trail spiral pattern.
4. Sew the triangles together to form squares, using a consistent ¼" seam allowance throughout. Press seams open.
5. Join the squares together to form the Snail’s Trail block, matching seams carefully. Pin seams in place and sew with a ¼" seam allowance. Press seams open.
6. Repeat to make as many blocks as desired.
7. Join the blocks together to create your quilt top. Arrange them in different orientations for varied effects. Press seams open and add any borders or finishing touches as desired.

Happy quilting!

Four Patch Piecing

The secret to a perfect four patch is pressing seams so they butt together when joined. You can make a four patch by cutting individual squares (great for scrappy quilts) or using pre-joined strips for speed.

Cut two A squares and two B squares in your required size. Using chain piecing, join an A square to a B square, right sides together, with a scant ¼" seam allowance. Press toward the dark fabric. Your result:

Press all seams toward the dark fabric so they butt up. Place the two A/B units right sides together with butted seams, pin if needed, and join with a scant ¼" seam allowance. Press.

Wider Application

This technique applies to all kinds of four patch blocks. As long as a block has a 4×4 grid — no matter how many pieces — the basic principles apply. Keep pressing seams in pairs of opposite directions and piecing will be smooth sailing.

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".