In quilting, some seams take you from squares to Half Square Triangles

Welcome to Wednesday! In only 2 more days our Boho Beach picnic quilt will be finished and ready to use!

With so many beautiful colors to choose from in the Banyan Batiks Boho Beach collection of fabrics, making a choice is a challenge, but, choose we must. So, to go along with the White on White background fabric, I selected a fabric from the Aqua and the Berry colorways of the Boho Beach collection fabrics along with the White on White.

These Aqua and Berry fabrics with the White on White on white make a great combo for Half Square triangles.

Yesterday, we made half-square triangles (HSTs) using the grid method.

Today, we’ll use squares and some easy algebra (this is coming from a guy who struggled BIG time with algebra in high school) to make HSTs. Back to school we go with Paul-style math!

As mentioned, this technique is easy. We simply need to draw a large X inside a square like this one as shown:

Making an X on a square piece of fabric is the 1st step to make easy Half Square Triangles.

Looks easy, doesn’t it? It is! The only length you need to calculate is the length of each of the diagonal lines you’ll draw.

To calculate just remember you need to add ⅞” to the desired finished size of the square.

Today we’ll be working on 8” x 8” finished squares or 8⅞” x 8⅞” unfinished squares. If you’re afraid it’s too close for comfort round it up to 9”.

TIP This technique will work well on a larger piece of fabric such as a fat quarter. Since we’re working on large squares for today’s technique, a 13” x 13” square will suffice.

Now here’s the ‘tough’ part: the length of each diagonal line = the length of one of the unfinished square sides x 2.

For example: Square side of 8⅞” x 2 = a diagonal line that will be 17¾”. Write the formula on a sticky note and paste it on your wall.

Diagonal lines are twice the length of the size of the unfinished of the 8⅞” block.

After you drawn the X on the lighter colored background fabric, draw a square around it. Pair each of your 2 color choices with the background fabric, right sides together.

From the end of every diagonal line make a line from corner to corner.

The next step is simply to sew along the outside vertical and horizontal lines framing the square.

Sewn along the lines on the square.

Carefully cut along each of the diagonal drawn lines to obtain 4 triangles. The continuous line sewn around the edge of the square holds the two pieces of fabric together. If you have made a larger than need square you may also wish to trim the outer edge.

Trim the outer edge of the square then cut on the diagonal line.

Press each triangle open to reveal the square, pressing the seam towards the darker fabric.

Press the Half Square Triangles to the darker fabric.

For today’s homework: make a total of 36 HSTs; 20 of one of your color choices and 16 of the other color.

Half square triangles done using the grid method

Join me tomorrow, when all the selected fabrics from the Boho Beach collection are placed together make up an exciting quilt top. I’ll also show you the fourth method for making HSTs!

This is part 3 of 5 in this series.
Go back to part 2: Making multiple Half Square Triangles using the grid method

Go to part 4: Making Half Square Triangles out of fabric strips

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JanetK June 26, 2019 - 9:05 am
I love the versatility of the Half Square Triangles!
Cassandra D June 9, 2019 - 6:29 am
Thank you for the information.
Paul Leger June 9, 2019 - 7:53 am
You are very welcome.
Gale June 5, 2019 - 4:47 pm
Paul Leger June 5, 2019 - 5:13 pm
Thank you Gale
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