Make This: Half-Square Triangle Piecing Tutorial

Today’s quilting tutorial may be a bit basic for all you seasoned quilters, but it’s also an important part of your quilting knowledge arsenal: the Half-Square Triangle (HST).  When fabric is cut diagonally (or, along the bias), there is a lot more stretch for you to try to control.  This can create some wonky situations for you.  No need to fear, though, just knowing this can be helpful.  The method we love for half-square triangles eliminates a lot of the trouble that comes with sewing on the bias.  Let’s get started, and you’ll see what we mean.

To pieces half-square triangles, you will need fabric squares of any size.  For our project, we used precut 7″ squares from Riley Blake’s Rocket Age line.  This is a little preview of another baby project we are working on, along with our Little King Quilt. To figure out how big to cut your squares to end up with a certain size of block, you can use this Half-Square Triangle Formula: Finished Size + 7/8″.  Although, it is important to note that this is a bit flexible because of the stretch of the fabric.  Our squares started at 7″, and our blocks ended up 6″.

Next, you will want to pair your squares and stack them with right sides together.  We tried to make each pair of squares as contrasting as possible.

Draw a diagonal line on the back of each square.  We like to use Frixion pens, because the line disappears with the heat from the iron.

Using a 1/4″ seam, sew down one side of the diagonal line.  We are using a 1/4″ piecing foot, so either side of the foot is a great guide.  By sewing the diagonals before the squares are cut, you can eliminate some of the trouble that comes with sewing on the bias.Sew along the other side of the diagonal on all your squares.This is what the squares will look like when they’re done. Cut along the diagonal line.Press both halves open.  You will have two identical half-square triangle blocks from each pair of squares.  You will also want to trim those little corners that are sticking out on each of the diagonal corners.  This will help reduce bulk in the seams.

Cut along all the diagonal lines, and press all of your squares open.  Be careful not to stretch the squares along the diagonal with the iron.

Now, lay out all your squares in the order you want them.

Assemble blocks into rows with a 1/4″ seam.

There you have it!  Easy peasy.  This is a great method for precut square packs.  We will be using our half-square triangle pieced top as part of another project, so stay tuned to see what we do with it.  What’s your favorite pattern for precut squares?

-Audrey