Spiderweb Quilt Block Tutorial

These 8” Spiderweb Blocks are easy to make and are a great way to use up tiny scraps. I used a technique called foundation piecing, which means that the pieces of the block are sewn to a stabilizing “foundation.” Spiderwebs and other string blocks (blocks that use lots of skinny strips of fabric) can be foundation-pieced to paper, which is torn away after sewing. However, for these small blocks, I used a fabric foundation, which doubles as the solid part of the blocks.

Using a fabric foundation will make your blocks a little bit heavier (since much of the block is, essentially, two layers instead of one) but don’t worry! I’ve employed a little trick to make sure that there won’t be too much fabric clogging up the corners where multiple points meet. 

For my blocks, I used print fabric scraps measuring 1” – 2.5” wide and up to about 6” long.

Using a foundation (paper or fabric) is a good, quick way to sew together a bunch of small, unruly strips. Because of the stabilizing foundation beneath, you don’t have to worry about the direction of the grain on the scraps you’re piecing. Even if they’re wonky or bias-cut, the foundation will keep everything orderly!

One advantage to having a paper foundation under scrappy blocks like this is that the foundation “contains” the seam allowances created as you add scraps to the block, so you won’t have to worry about them getting caught on your machine’s feed dogs when you join the blocks.

The Spiderweb Block is based on a simple Quarter-Square Triangle shape.  For an 8” Spiderweb Block, you’ll need a 9.25” square of a stable, solid fabric. (I used Kona cotton.) Lay the solid square on your cutting board and use your ruler and rotary cutter to cut it in half diagonally, corner-to-corner. Make a second cut between the other two corners, creating four triangular pieces.

Tip: Want to make Quarter-Square Triangle blocks in another size? Start with squares that are 1.25” larger than the finished blocks you want to make.

Okay, this is the fussy part. It’s time to mark each triangle so we know where to start sewing the scrappy strips. Use a fine-tipped fabric marker or a pencil. If you’re using a pencil, protect your pressing area with scrap fabric (as the heat from your iron may cause pencil marks to migrate). Remember also that disappearing ink disappears. If you’re making a whole bunch of blocks or don’t plan to sew all your blocks right away, a water-soluble marker is probably a better choice. Use a fine mist spray bottle to make the ink “disappear” when you’re finished sewing.

Position each triangle, wrong side up, as shown in the above photo and use a ruler and your marking tool to make the following marks on the wrong side of the fabric.

1. Measure a short line .25” from the bottom of the block.

2. Use the line you just marked and the top center of the triangle to mark a dot at the center of the block, .25” from the bottom.

3. Mark a dot on each side of the triangle, 2” from the top point.

4. Draw a line between each of the dots on the top sides and the dot at bottom center, creating a kite shape that will be the center of the finished block.

Tip: In theory, you should choose one side of a solid fabric as the “right” side. In practice, it’s often impossible to keep track of which side is which. If you don’t notice a difference between the two sides, chances are that nobody looking at your quilt will be able to either. Don’t stress about it. It’s not as though one side is more structurally sound than the other!

Repeat until you have enough pieces. You’ll need four triangles for each 8” block (16 if you want to make a 16” mini quilt like mine). 

Place a triangle face down (so with the marked lines facing up) on your work surface. Slide one of your scrap strips under the triangle (right side facing the triangle) as shown in the photo above. The strip should be mostly under the “kite” part of the triangle, but at least .25” should extend beyond one of the marked lines. Once the strip is properly positioned, sew along that marked line, joining the strip to the triangle.

Flip the triangle over and press the strip outward from the center. Place a second scrap strip; face down on the strip you just sewed. Lining up the edges of the strips (as shown above) is optional. You can piece the subsequent strips wonkily. Just make sure there’s at least .25” of overlap between the two pieces before you sew the second piece to the triangle. Press the second strip outward from the center. Continue adding pieces until the point of the triangle is covered.

Repeat these steps to add scrap strips to the other half of the triangle. 

You’ve probably noticed that the “right” side of your triangle no longer looks much like a triangle! Flip it over and trim it back to size, using the foundation triangle as a guide.

Repeat the last few steps to make 3 more (4 total) pieced triangles.

Using the seam allowance where the outermost scrap strip was joined to the foundation as a guide, trim away the foundation fabric under each point. This will make the block intersections less bulky.

Using a quarter inch seam allowance, pressing seams open, and following the layout shown in the above photos, sew the four triangles together into an 8.5” square block. You’ll probably notice that a single Spiderweb block doesn’t look much like a spiderweb! That distinctive octagonal shape is actually a secondary pattern created by joining multiple blocks. You can make a 16.5” square mini quilt like I did by joining 4 blocks. This will create a pattern with a complete web shape right in the middle.

For a mini quilt like mine, you’ll need approximately 18” x 18” of batting and a 20” x 20” piece of backing fabric. For binding your mini quilt, 2 strips 2 1/2″ x 40” (width of fabric) should be enough.