Sewing Y-Seams and Tumbling Blocks

How to sew Y-seams and Tumbling blocks tutorial from Clever ChameleonFrom the Sewing Room – Sewing the Jewel Tone Diamonds Tumbling Blocks Quilt (Part I)

Jewel Tone Triangles color scheme from Clever ChameleonOver the last few weeks I have been working on a new project stemming from Colour Inspiration Tuesday. It all started with the Jewel Tone Triangles colour scheme.

The Jewel Tones Triangles colour palette sparked an idea that immediately appealed to my daughter. It was a small tumbling blocks quilt design with drifting colour transitions between the blue-greens and the pink-purples. I chose tumbling blocks for the design because this photo cries out for some sort of 3D design. And now my daughter wants it for her bed. ASAP.  She loves the colours and is fascinated by the 3D effect. But the design was never really intended to be made, let alone in bed-size!

Anyway, fast forward a week or two, and by the time Jewel Tone Triangles went to press, my daughter had convinced me to do it. She has grown out of her Disney Frozen themed quilt (fair enough) and she feels entitled to a quilt upgrade! You can read about the evolution of the Jewel Tones Diamonds quilt design in this post.

Coming to grips with the Jewel Tone Diamonds Quilt Design

But it is easy to draw up a quilt plan without any thought to the difficulty of construction. Which is, of course, exactly what I did with Jewel Tone Diamonds. I was primarily playing with colour relationships and colour values. Not intentionally designing a quilt to make.

So I am mildly embarrassed to say, that the shear number of Y-seams in this design caught me a little by surprise. Simply through a lack of forward-thinking. So it wasn’t really until my daughter and I had modified the design to fit her bed, bought the fabric, cut the fabric and laid it out, that the Y-seams situation dawned on me. A fact for which I am actually thankful, because it is a skill I am well-overdue to learn and may otherwise have dodged yet again.

How to sew Y-seams (also known as set-in seams)

Failed tumbling blocks
Don’t worry if your first attempts at tumbling blocks aren’t great. This is what my first two Y-seam attempts look like!! Meh!

Until this project, I had never sewn tumbling blocks before. So I did a bit of internet research. The most useful resource I found was this video by the Fat Quarter Shop

Fast forward another couple of weeks, and I am about halfway through sewing Jewel Tone Diamonds. I am now quite confident at Y-seams and actually enjoy sewing them! Figure that!! Not what I expected! There is something about opening up the piece and seeing it lie flat that I find intensely satisfying. 

I know that I am not alone in my (turns out, unjustified) fear of Y-seams. There are plenty of no-Y-seam tumbling blocks patterns out there to prove it. But it turns out that Y-seams are not that hard! Easier than matching points, actually. So, I have decided to show you how I conquered them. Stick to this formula and you might be as pleasantly surprised as I am.

Tumbling blocks improvement
My next attempts at tumbling blocks are much better!!

What you will need……

  • Some fabric diamonds. To get the exact tumbling blocks effect you see here, the diamonds must have 4 sides of equal length and two 60° angles and two 30° angles. The size of the diamonds is completely up to you, but don’t go too small. You don’t want to end up with frustratingly small pieces. Diamonds with 4-5″ sides are easy to work with. I had left overs after cutting my quilt, but diamonds made from scrap fabric will also do. I cut my diamonds with my diamond die and GO! cutter. If this is not an option for you, you can also cut diamonds from fabric strips using a ruler that has a 60° angle marked on it. Accuracy is key though. If your diamonds are sloppy, the piecing will be a nightmare.
  • A presser foot with a quarter-inch guide for your sewing machine. This method relies very heavily on this. This foot gets rid of the need to mark each and every seam allowance at the corners. I don’t have the time or patience to mark hundreds of seam allowances!
  • Your sewing machine set to a shorter stitch length than usual. Mine defaults to setting “2.5”. I turn it down to “2” for this. The shorter stitch length is important to make sure no seams start to unravel as you sew in the third diamond. It also helps you stop in the correct place at the corners, without over-shooting the seam allowance by half a stitch.
  • A hot iron. Quality spray starch is also useful.

Sewing Tumbling Blocks Step One

Take two diamonds and lay them one over the other, right sides together. Starting from one of the pointy ends (30° angles), sew a quarter-inch seam towards one of the wide corners (60° angles). 

sewing tumblng blocks step one
Sew a quarter-inch seam allowance from the pointy end of the diamond towards a wide corner.

Stop when you get to a quarter-inch before the end. Reverse sew for a couple of stitches and break thread.

sewing tumbling blocks step one
Stop one quarter-inch from the edge of the diamond pieces.

How do you know when you are 1/4 inch from the end?! When you think you are close, stop with the needle in the down position and swivel the diamonds so that the sewing line is now down the next side of the diamonds. If the quarter-inch guide rests on the edge, you are in the right place (see photo below). Swivel the fabrics back to the correct position and secure with backstitch. 

Sewing tumbling blocks step one
Swivel your diamonds to pretend to sew down the next side. If the 1/4 inch guide lines up with the edge you are in the right spot. This is perfect. Backstitch along the newly sewn seam.

If fabric peeks out to the right under the quarter-inch guide (see next photo), swivel the diamonds back to the correct direction, stitch the required number of stitches to cover the gap you observed and re-check your position. Secure with backstitch.

Sewing tumbling blocks step one
If you swivel your diamonds and it looks like this, you have not sewn far enough. Swivel your fabrics back and take another stitch or two.

If you swivel your fabrics and find you have gone too far, there is nothing for it but to unpick the overshot stitches. Sorry. Learn to stop too early rather than too late.

Sewing Tumbling Blocks Step Two

Take your diamonds out of the sewing machine. Your first seam should look like this.

Sewing Tumbling blocks step two
See where the seam stops?

Open up the diamonds, lay flat and press the seam open.

Sewing tumbling blocks step two
Press seams open. Add a little starch if you wish.

Sewing Tumbling Blocks Step Three

Layer your third diamond underneath the two joined pieces, such that one of the narrow points lines up with the top dog-ear of the fabric on the left. The top right edge lies along the edge of the diamond on the right and the large corner lines up with the large corner of the diamond on the right. If you have sewn an accurate quarter inch seam in step one, this should be straight-forward.

Sewing tumbling blocks step three
Layer the third diamond under the sewn pieces so that the narrow corner lines up with the dog-ear of the left diamond and the wide corner lines up with the diamond on the right. (Note: this set is not quite lined up yet. Keep moving the third diamond under the righthand diamond until it is completely covered.)
Sewing tumbling blocks step three
When you have done this correctly, you should see a corner of the new diamond peeking out when you lift the left diamond at the seam allowance you left un-sewn in step two.

Start sewing a new quarter-inch seam from the free narrow corner of the right-hand diamond. In the picture above this is the bottom right corner. You will be sewing towards the end of the first seam that terminated before the seam allowance. When you get about two-thirds of the way along the seam, pause.  

Sewing tumbling blocks step three
Sew the second seam towards the wide corner where the seam terminated at the seam allowance.

Now fold the left hand diamond corner out of the way until it opens up the un-sewn portion of the first seam. Hold the folded corner out of the way as you sew the rest of the seam. Sew to the very edge of the first diamond, including over the seam allowance, but do not stitch into the folded back diamond.

Sewing tumbling blocks step three
Nearly there. Keep sewing this line until you reach the intersection of all three fabrics. Stop and backstitch.

Secure with a couple of backstitches and cut thread. Your work should now look like this photo below.

Sewing tumbling blocks step three
When you place your sewing down flat it should look like this. The new seam goes completely from one edge of the right-hand diamond to the other, but absolutely NO further..
Sewing tumbling blocks step three
If everything has gone to plan, you will still be able to lift the corner of the left-hand diamond to reveal the corner of the third diamond, like this.

Open up your sewing, lay the pieces flat and press the seam open.

ing tumbling blocks step three
It is starting to look like a tumbling block, but with one seam still not sewn.

Sewing Tumbling Blocks Step Four

The final step! Fold the diamond that has two attached sides in half so that the second and third diamonds line up over the top of each other. It will look like the photo below.

sewing tumbling blocks step four
The first diamond is folded in half across the width, which causes the other two diamonds to lay one over the other with their edges aligned.

Sew a quarter-inch seam from the wide corner at the top middle of the photo above, to the thin corner top right. This direction of sewing is important. Doing it this way prevents any excess fabric being pushed to the centre of your Y-seams. There shouldn’t be excess fabric, but if there is a little, it is harmless on the edge of your tumbling block. If it is in the centre, your block will bubble and not sit flat. Remember, sew from the wide to the pointy end, and it will all be good!

Sewing tumbling blocks step four
Sew from the wide corner to the pointy corner.
Sewing tumbling blocks step four
Your sewing will now look like this

Now you are done with the sewing. Open up your tumbling block and press the last seam open.

Sewing tumbling blocks step four - perfect Y-seams
Open up your tumbling block and press the last seam open.

Flip your tumbling block over. Press one last time and voila! A beautiful Y-seam.

Sewing tumbling blocks step four
Finished tumbling block. Time to do a little happy dance!

You’ll be a tumbling blocks/Y-seams pro before you know it!

Once you conquer this method, the Y-seams go together like clockwork. I promise! When I do these steps in this order, Y-seams work every time. It honestly feels a little like magic!

Clever Chameleon logo

In my next post I will tell you more about how I put the units together to make the quilt top. There is one way I think gets the easiest matching points. And while I am enjoying the Y-seams, I am not celebrating all the matching points! I’ll add the link here once the post is up…. or subscribe to get it delivered straight to your inbox.

Until then, keep Quilting Your Own Story!

Now it's your turn.... what do you think?