Half Square Triangle Piecing Tip

Half square triangle piecing tip

Before I was a quilter, I sewed primarily garments. I still have lots of garment sewing tools in my toolbox, and I’ve found a new use for one of them in quilting. I found that my tracing wheel has been helpful in temporarily marking fabrics for stitching patchwork and quilting. Here’s how I’ve been using my tracing wheel to make quick half square triangles (HST’s). Use this tip with any straight stitch foot!

Materials to stitch quick half square triangles

  • Tracing wheel
  • Rotary cutter, mat, and clear acrylic ruler
  • Sewing machine (I use a BERNINA 770 QE)
  • Straight stitch foot and needle plate for quilt piecing (I use the Patchwork foot #97D)

Half square triangle piecing tip

First, cut your fabric into squares. Your HST blocks will be about 1/2″ smaller than the squares that you start with. Layer two squares right sides together on your cutting mat, one on top of the other. Align your clear quilting ruler on top of the square with the first quarter inch mark from the edge. Make sure your quarter inch mark on the ruler is matching two opposite points of the square as in the photo above.

Half square triangle piecing tip

Now grab your tracing wheel, and press firmly along the ruler’s edge. Make sure you’ve got a firm grip on the ruler so it doesn’t slip as you’re pressing in the first line with the tracing wheel.

Half square triangle piecing tip

Flip the square over and mark the other side in the same way. These two marks are the stitching lines, they will be easy enough to follow along when you sew, and will disappear entirely when you press your HST’s.

Half square triangle piecing tip

Set up your sewing machine for quilt piecing; I use a straight stitch needle plate and Patchwork foot #97D to optimize the straight stitch on the machine. You can use whichever piecing or straight stitch foot you prefer, and a straight stitch needle plate if you have one.

Half square triangle piecing tip

Stitch along the first line, following the mark you’ve made with your tracing wheel.

Half square triangle piecing tip

Next, stitch along the second line. Here’s a fabric tip: if you are working with fabrics that seem to shift as you’re sewing along the marked lines, try sewing both lines in the same direction instead of flipping the square over to sew the second line in the opposite direction. You can also use the Dual Feed feature to keep fabrics from shifting, or try the Walking foot #50.

Half square triangle piecing tip

Take your stitched square back to your cutting mat, and cut from corner to corner in between the stitched lines.

Half square triangle piecing tip

Press your HST’s well after cutting. You can press your seams as desired – open, or to one side or the other.

Half square triangle piecing tip

And finally, give your freshly pressed HST’s a trim to square-up and remove the extra seams.

Half square triangle piecing tip

A quick and easy way to stitch up a bunch of HST’s!

10 thoughts on “Half Square Triangle Piecing Tip

  1. In order to insure accurate size of HST why not mention cutting 7/8″larger than desired finished size, then measuring finished size and trim up. It is sooooooo easy to sew just a tiny bit off the tracing wheel and get a wonky HST….or different finished sizes…

  2. This technique may be great for a beginner to learn…however it is extremely labor intensive if you have hundreds of these to make for a quilt….basically all that is needed is to align the two squares RST, pin if desired, draw a line from corner to corner or use the tracing wheel, which is obviously a great way to avoid markings on the fabric, and stitch a quarter inch on either side of the line. If using the tracing wheel in this application, I’d probably use one of the papers that came with the wheel, to make a visible cutting. Less measuring, less marking, less time. Sorry, but the method above is just too time consuming when doing a large volume of HST’s.

    1. Hello Peggr, thanks for your comment! Yes, marking the center line and following with an accurate quarter inch piecing foot is an excellent tip. As mentioned in my article above, I wanted to give readers a tip to use even if they do not have a quarter inch foot so they can still be successful with this method to create HST’s. Happy stitching! – Erika

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