Top 3 Methods for Sewing Half Square Triangles
Have you ever made a Half Square Triangle?
The Half Square Triangle, often referred to as HST, is one of the most common quilt blocks used in both modern and traditional quilting. If you’re new to quilting it’s certainly one of the first quilt blocks you will want to learn. The exciting thing about the HST is that there are so many different ways to make them. We are going to cover the four most common ways to make HSTs and why you would choose each method.
Pictured above is the Showcase Quilt pattern by Love Sew Modern made in the George, Gertrude, Mallory & Maude Fabric Collection.
Two-At-A-Time Method
The Two-At-A-Time method is probably the most commonly used method for making HSTs. As it implies in the name, this method creates two HST at once. This method is great because it doesn’t add any bias to your blocks. What’s bias you ask? Bias is when the fabric isn’t cut against the grain and therefore can become stretchy or mis-shapen. So if you’re new to quilting, this method will be great to use. I also find that the Two-At-A-Time method uses less fabric than some of the other methods, which is always a bonus.
The standard rule of thumb is to cut your HST pieces ½” larger than the finished size you want your HST to be. For example if you want your HST to be 3 ½” square you would cut your squares at 4”. This has your HST finishing at exactly 3 ½” and not leaving much room for errors or squaring up your blocks. Because of this I always cut mine at ¾” larger than the size I want them to finish at. So if I’m making a 3 ½” HST I would cut my pieces at 4 ¼” square.
3.5 + .75 = 4 1/4” square
You can use this Cut Chart to practice making your own HST using the
Two-At-A-Time Method!
Four-At-A-Time Method
You’ve guest it! The Four-At-A-Time Method creates four HST at once. This can be really handy when sewing blocks that require four of the same HST, like the Pinwheel. The downside to using this method is that it does add bias to the outside edges. Incase you missed it, bias is when the fabric isn’t cut against the grain and therefore can become stretchy or mis-shapen. If you don’t over handle your pieces, or stretch them while ironing this isn’t an issue.
So how do we calculate the fabric square sizes we need when using this method? It’s a little more complicated math than the Two-At-A-Time, but you’ve got this. You’re going to divide your HST size by .64 and then add .25. I always round up to my nearest 1/4”. For this example we’re making 3 1/2” HSTs.
3.5 / .64 = 5.47 + .25 = 5.72 Rounded to the nearest 1/4” = 5 3/4” square
You can use this Cut Chart to practice making your own HST using the
Four-At-A-Time Method!
Eight-At-A-Time Method
When you have a project that uses a lot of HSTs or is made up of nothing but HSTs you might want to try the Eight-at-A-Time Method. This method is very similar to the Two-At-A-Time Method, but uses much larger squares. Like the Two-At-A-Time, the Eight-At-A-Time doesn’t create any bias edges. Since the squares can become large with this method it’s important to pin our pieces together. This prevents them from shifting as we work.
The math for Eight-At-A-Time HSTs are a little more simpler than the Four-At-A-Time method. First you add 1” to the finished HST size. Then you multiple it by 2. For this example we’re making 3 1/2” HSTs:
3.5 + 1 = 4.5 x 2 - 9” squares
