Half Square Triangles – 2015 BOM – Month 1

Welcome to the first month of the 2015 Technique Block of the Month. Each month, you’ll learn a new technique as you complete the block for the month. This month, we’re making half square triangles. These units are used in hundreds of different quilt patterns, and there are many different techniques for making them – we’re going to use the simplest.

Fairfield Technique Block of the Month - Month 1

Before you start this block of the month, be sure to check out the fabric requirements for either the solids version of this quilt, or the patterned version of the quilt. You’ll want to purchase all the fabric before you get started so that you have it on hand, and so the store doesn’t run out of the fabrics you’ve chosen!

For your Half Square Triangle block, you have two options – you can make the heart, or the boat. The basic construction for each is the same. Here are the fabrics you’ll need to cut:

Heart block

Fabric A (red or pink/white dot):
6 – 3 1/2″ squares
4  – 3 7/8″ squares
Fabric B (purple or blue/pink dot):
2 – 3 1/2″ squares
4  – 3 7/8″ squares

Sailboat block

Fabric A (light blue):
5 – 3 1/2″ squares
3  – 3 7/8″ squares
Fabric B (dark blue):
2  – 3 7/8″ squares
1 – 3 1/2″ x 12 1/2″
Fabric C (red):
2 – 3 1/2″ squares
1  – 3 7/8″ squares

Start by making your half square triangles. Each pair of 3 7/8″ squares will make two HST units. Here I’m pairing the red and light blue, which will make the two sides of the boat.

Using a ruler and a pencil, draw a diagonal line across the square.

draw diagonal line

Place the two squares on top of one another (right sides together – meaning that the “pretty” sides of the fabric are touching, if you’re using a print and not a solid), and stitch 1/4″ away from the line, on both sides.

stitch on each side

Use scissors or a rotary cutter to cut down the line.

cut in half

Press the block open, with the seam allowance to one side. Once you’ve made all the half square triangles you need for your block, lay all your pieces out, in order. Stitch the blocks together into rows, using a 1/4″ seam allowance.

stitch together rows

Press the seams on your rows. Alternate the directions you press the seams. On the first, if you press towards the right, press to the left on the second, then to the right again on the third. This will help you line up your points.

Stitch the rows together, one at a time. Lay the two rows together, matching up the seams. The top and bottom seams will push right up against one another – this is called “nesting” the seams. Stitch together using 1/4″ seam allowance.

nest the seams Half Square Triangles

Once all the rows are together, you can press the horizontal seams. No need to alternate directions – these can all be pressed in the same direction.

Your block is complete! Put it aside as we continue next month with block 2… or you can use this block to make this month’s project – a draw-string laundry bag!

2 thoughts on “Half Square Triangles – 2015 BOM – Month 1”

  1. VickiT says:

    I’m confused why this has such a recent date of July 28, 2015. I was following this Technique BOM and the projects made from each as well back when it first started on Feb 2, 2015 and had downloaded the first 3 months but then it just stopped.
    Is this starting over again and will continue beyond the 3rd block, which was the Prairie Point?

    Thank you

    1. Niki Meiners says:

      Vicki,
      Sorry for the confusion. We are in the process of loading the BOM to both the blog and our project gallery. You can see all the projects https://www.fairfieldworld.com/project/designer/carolina-moore-master-maker/ . You can expect to see another post with links to each month.

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