Half Square Triangles

I recently had two quilters question instructions on making HSTs, so I thought I’d go over my method for making HSTs.

It’s actually not MY method, I learned it from Eleanor Burns on Quilt in a Day close to 40 years ago. It’s the only way I’ve made HSTs.

It starts with a grid of squares. One square of two different fabrics make two HSTs. That means that you draw a grid on the back of one fabric equal to HALF the number of HSTs you need to make.  After you draw the grid, you draw diagonal lines. The diagonal lines are your sewing guidelines, you sew ¼” away from each side of the diagonal lines. You can see a post I did on December 1, 2018.

This is a grid of 8×4. But I didn’t need all of them, so I didn’t draw the last 2, indicated by the *. As it turns out, the fabric I was using was 45″ of usable fabric, so I was able to draw 9 squares across the width, and the grid actually looked different than above, and I ended up with 2 larger rectangles left over.

After drawing the grid, I draw the diagonal lines, the seamlines are indicated by the red dash lines. I can start sewing at an edge, sew to the other edge, turn and keep going until I’ve sewed on both sides of the diagonal lines.  Then I cut on all drawn lines–the grid lines and the diagonal lines.

I took some pictures the other day at work when I was working on a sample. I needed HSTs using three different fabrics. One fabric was used with both of the other two fabrics. From the one fabric I cut a WOF strip, the other two I cut the half the WOF (these two were FQs). It’s hard to work with a full WOF on top of two half WOF, so I drew the grid on the two smaller fabrics. It was a little harder to see because they were darker. I could have cut the larger piece in half to make two half WOF pieces of that, but I guess I didn’t think of that at the time (or I was thinking doing this post??).

I have the Quilt in a Day Triangle Square Up ruler. With this ruler the trimming is done before opening the HST–you only have to make two cuts–the right and top. After trimming the sides and the dog ears, you press the HST open. (I don’t mean you have to press the seam open, only that you open up the triangle to make it a square shape.)

These are HSTs that finish at 2″, so the 2½” line on the ruler is what I lay on the seamline and trim the sides and top. I didn’t show the ruler on the previous picture, but you can see it on that line here when I trimmed the dog ears.

You can also simply use a scissor to trim the dog ears. That’s a faster way.

I hope this helps to understand my way of making HSTs.

Happy Sewing!