Disappearing Hourglass Tutorial: Jenny Doan's Easy Layer Cake Method

There's something almost magical about the "disappearing" quilt block technique — you start with a simple block you've seen a hundred times, make a few strategic cuts, rearrange the pieces, and suddenly you've got a design that looks like it took hours of complicated piecing. Jenny Doan's Disappearing Hourglass quilt is the perfect example. With just a layer cake and some background fabric, you'll create stunning, intricate-looking blocks that are secretly one of the easiest patterns in quilting.

With over 1.2 million views, this tutorial has helped quilters everywhere discover how a few simple cuts can transform basic half-square triangles into a show-stopping design. If you love shortcuts that don't compromise on beauty, this one's for you.

▶ Watch the Full Tutorial

What Is a Disappearing Hourglass Block?

An hourglass block is a classic quilt block made from four half-square triangles arranged so their points meet in the center, creating a shape that looks like — you guessed it — an hourglass. You've probably seen it in traditional quilts for generations.

The "disappearing" part is where the magic happens. After you've sewn your hourglass block together, measure it and divide the size by 3 to turn it into a nine-patch.

You will make four cuts from the center seam on all four sides, being careful not to move the block as you cut. Then you rearrange and rotate the pieces to create a completely new design. The original hourglass pattern seemingly vanishes, replaced by a modern, complex-looking arrangement that will have other quilters asking, "How did you do that?"

What You'll Need

🧵 1 layer cake (10" squares) of print fabric — or 36 ten-inch squares cut from yardage. Shop precut fabrics.

🤍 36 ten-inch squares of background fabric — white or cream works beautifully for contrast.

✂️ Rotary cutter, ruler & cutting mat — you'll be making lots of precise cuts. Shop rotary cutters.

📐 Square-up ruler — a Block Loc or any squaring tool works great for trimming to 6¼". Shop quilting rulers.

🪡 Sewing machine with a ¼" presser foot

🔥 Iron and pressing station — press seams to the dark side throughout

Fabric math: One layer cake is approximately equal to 3 yards of fabric. Each pair of 10" squares (one print + one background) will yield four half-square triangles, and you'll pair four triangles into each hourglass block. With 36 pairs, you'll have plenty of blocks for a generous lap or throw quilt.

Step-by-Step Instructions

Step 1: Make Half-Square Triangles

Start by taking one 10-inch print square and one 10-inch background square. Place them right sides together, aligning all edges carefully.

Sew all the way around the outside of the stacked squares using a ¼-inch seam allowance. Yes — all four sides, just like you would for a disappearing four-patch!

Once you've sewn all the way around, use your rotary cutter and ruler to cut diagonally corner to corner in both directions, making an X through the block. You'll end up with four half-square triangle units from each pair of squares.

Jenny's tip: "The most important thing in making this is that your seam allowance is the same on all four sides. Just watch when you sew and make sure it's the same."

Step 2: Press and Square Up

Press all your half-square triangle units open, with the seam toward the dark side. This keeps the darker fabric from showing through lighter backgrounds.

Now use your squaring ruler to trim each unit to 6¼ inches. Line up the diagonal seam with the 45-degree line on your ruler, make sure you have clean edges on two sides, then trim. Rotate and trim the other two sides.

Jenny's tip: "If you iron to the dark side, the words on your ruler always go on the background side. That helps you line everything up perfectly."

Half-square triangles arranged into the classic hourglass formation

Step 3: Assemble the Hourglass Block

Take four half-square triangle units and arrange them into a traditional hourglass pattern: two units with the dark triangle pointing up, and two with the dark triangle pointing down, so the dark triangles form a bowtie or hourglass shape in the center.

Make sure the white (background) triangles meet in the middle on two sides, and the colored triangles meet in the middle on the other two sides.

Sew the four units together — first in pairs (top row and bottom row), then join the two rows. Nest your seams at every junction so your points line up beautifully.

Jenny's tip: "If you put these back together, you can see that those seams come right together. Just make sure they're all lined up real nice — nest up those seams!"

Step 4: Press and Prepare for the "Disappearing" Cuts

Press your completed hourglass block open. Check that all seams are lying flat and your points match up nicely in the center. This is a great time to use a rotating cutting mat — it makes the next step so much easier.

Locate the center seam line that runs through the middle of your block. You're about to make the cuts that transform this ordinary hourglass into something extraordinary!

Step 5: Make the "Disappearing" Cuts

Here's where the magic happens! After you've sewn your hourglass block together, measure it and divide the size by 3 to turn it into a nine-patch; divide this number by 2 to determine where you need to make your four cuts from the center seam on all four sides, being careful not to move the block as you cut.

1. Find the center seam line running horizontally through your block.

2. Measure the correct distance (as noted above) from that center line and cut.

3. Rotate the mat and cut the same distance from the center on the opposite side.

4. Now find the vertical center seam and cut the same distance from the center on both sides.

You should now have 9 pieces — a center section, four side pieces, and four corner pieces. Don't panic! The rearranging is the fun part.

Step 6: Rearrange and Sew the Disappearing Block

Now comes the creative part! Take your 9 pieces and rearrange them. The key is to rotate certain pieces to create a new design:

Row 1: Turn the corner piece out, leave the middle piece, turn the other corner piece in.

Row 2: Turn the side piece sideways, keep the center as is, turn the other side piece sideways.

Row 3: Mirror the pattern from Row 1.

Sew the pieces back together in three rows, then join the rows. Press all seams, and marvel at how different your block looks! The original hourglass has completely disappeared, replaced by a stunning geometric design.

Jenny's tip: "When I started doing these blocks, I never squared them and I should have. Squaring makes everything come together so much nicer."

Step 7: Assemble the Quilt Top

Continue making disappearing hourglass blocks until you have enough for your desired quilt size. Lay them out on a design wall or the floor, experimenting with the arrangement. The beauty of this pattern is that every block looks fantastic no matter how you orient it.

Sew the blocks together in rows, then join the rows. Add a border if desired — a simple 3-inch border in a coordinating fabric frames the quilt beautifully.

The "disappearing" cuts transform your block into a brand new design

💡 Pro Tips

Use a rotating mat: When making the four disappearing cuts, a rotating mat lets you cut all four sides without moving the block — much more accurate.

Square up after each step: Squaring your half-square triangles to exactly 6¼" and your hourglass blocks before cutting makes the final result much cleaner.

Try scrappy: This pattern looks gorgeous with a scrappy layer cake. The variety of prints in the rearranged pieces creates even more visual interest.

Press to the dark: Throughout the entire project, press your seams toward the darker fabric to prevent show-through.

🛒 Shop Layer Cakes & Precuts

The Disappearing Hourglass is one of those patterns that proves quilting doesn't have to be complicated to look impressive. With Jenny's straightforward method, you'll go from a stack of layer cake squares to a breathtaking quilt that looks like it was designed by a pro. Happy quilting! 🧵