2 at a Time Half Square Triangles

When I first started quilting half square triangles (HSTs) seemed pointless. I couldn't understand why anyone would spend time trimming the slightest bits of the edge of a HST. It seemed like a waste of time and like maybe it was a bit of an over kill.

That was then, and this is now. I have since become one of the people who spends my time trimming HSTs for days. Well, not for days, more like hours.

I've come to have a love/hate relationship for these little blocks. They are so versatile and useful in quilting, but also require time to trim.

HSTs can be made in a variety of ways. Today I am going to walk through how to make them two at a time.

Let's get sewing

1. First, let's talk about square size. To make 2 HSTs you will need 2 squares of fabric 1/2 in. larger than you want the trimmed size to be (not sewn in size). Example: If you want your HSTs to be 4 1/2 in. trimmed, then you will start out with (2) 5 in. x 5 in. squares.

If you want a little extra wiggle room for your HSTs, meaning extra trimming space, which I suggest if you are new to quilting. Then, cut your squares 3/4 in. larger instead of 1/2 in. So in the example you would cut your squares 5 1/4 in. x 5 1/4 in.

2. Place your squares right sides together, so the wrong side of the fabric is facing up. Draw a diagonal line from one corner to the other. I prefer to use a Frixion Pen to do this. The ink disappears when heat is applied.

3. Sew 1/4 in. on both sides of the drawn line. I like to sew a scant 1/4 inch seam to give me more space when trimming the HSTs.

4. Cut on drawn line.

5. Use a hot iron to set your seams by pressing them for a couple seconds. I like to then press the seam open. I think it gives a nicer press and allows for the half square triangles to be sewn into a quilt or project easier.

6. Trim the HSTs to 4 1/2 in. x 4 1/2 in. by using a ruler with a 45 degree line. Line up the diagonal seam with the 45 degree line and make sure that the block hangs below the 4 1/2 in. lines on the ruler. See image.


Trim off the side and top.

7. Flip block and line up the trimmed edge with the 4 1/2 in. lines on the ruler. Also, line the 45 degree line up with seam. Trim side and top.

Finished Half Square Triangle

When to the Use 2 at a Time Method

If you are sewing a large quantity of HSTs for a project and many of them are the same, then I suggest using the Four or Eight at a time method. An example of this would be the Little Three Creeks Quilt Pattern. Many HSTs are required, but you can make them in bulk because most of them are the same. 

However, there are some projects that require a large number of HSTs, but also require a large variety. An example of this would be Kailia's Quilt Pattern. The pattern has a lot of HSTs! But part of what makes the pattern visually appealing is having a large variety of HSTs, which means a little extra work has to go into making them 2 at a time.

You can see the Kailia's Quilt above. It has a large combination of HSTs.

I hope this little tutorial is helpful and I look forward to seeing your half square triangles! Make sure to ask any questions in comments or on Instagram (@thenomadicquilter).

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1 comment

Thank you for this very helpful tutorial! Your quilt is gorgeous and has inspired me to make one of my own out of scraps. thank you!


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