Half rectangle triangles (HRTs) are one of those intermediate quilting skills that can seem tricky at first, but once you’ve made a few and learn the right trimming method, they become incredibly satisfying and versatile. If you’re working through the Dilly Dally Quilt, you’ll get lots of hands-on practice. Four of the blocks in the quilt use HRTs!

Today, I’m sharing a new video tutorial from the Dilly Dally Quilt Class where I walk you step by step through how to make HRTs. This is a great warm-up before you begin your HRT blocks.

HRTs vs. Half Square Triangles: What’s the Difference?

While HRTs and half square triangles (HSTs) may look similar, they’re constructed differently and can’t be used interchangeably. Here are a few key differences:

• Shape: HRTs are longer and leaner, they are rectangular instead of square.
• Construction: You start with rectangles, not squares.
• Seam direction matters: The direction you draw your diagonal line will change the final angle of your triangle.
• Trimming is more precise: Because of their proportions, HRTs require more careful trimming to ensure accuracy.

Want to explore HRT-heavy quilts? Check out my patterns:

• Sugar Bear Quilt
• La La Fancy Quilt
• Moon Goddess Quilt

Play

My Favorite Way to Trim Half Rectangle Triangles

In the video, I demonstrate a trimming method that has completely changed how I work with HRTs. Here’s a quick breakdown:

1. Use washi tape to mark the unfinished size on your quilting ruler.
2. With a Sharpie, mark dots a ¼” in from each corner of your rectangle on the ruler.
3. Line those dots up with the seam line of your pressed HRT.
4. Trim with precision!

Don’t worry—Sharpie comes off with nail polish remover. This trick has helped me stay consistent and avoid wonky HRTs.

Video Links

• My Pressing Station (underneath my wool mat, I have a flannel/vinyl tablecloth protecting the table):
  • Iron
  • ​Wool pressing mat
  • ​Pressing spray
  • ​Misting bottle
  • Dingo pressing and cutting table
• Cutting Station
  • Rotary cutter
  • Basic 24″ ruler
  • Cutting mat
  • Magic Pins
  • Smaller subcutting ruler
  • Rotating cutting mat
  • 6 1/2″ square ruler or another one I like
  • Project box
  • Washi tape
  • Wool mat for block carrying
  • Stripology ruler – little one / big one
  • Ruler Grips
  • Quilt in a Day Half Square Triangle ruler
• Sewing Machine Station
  • Juki 2000 on Amazon or Juki 2000 at Sewing Machine Plus
  • Dura snips (hanging on my machine)
  • Snip a Stitch seam ripper
  • Sewing machine light
  • Daylight Slimline lamp 
  • Washi Tape
  • Diagonal Seam Tape
  • Sew Laser
  • Sewing cabinet 
  • Sewing chair 

Make One First, Before Starting Your Block

If you’re following along with Dilly Dally Quilt, I strongly encourage you to make a single HRT before diving into your first full block. It gives you a chance to test your angles, trimming, and pressing techniques without committing to the whole layout just yet.

Half rectangle triangles are a skill worth mastering, especially if you’re looking to take your quilt designs beyond the basics. With the right prep and a good trimming method, they’ll become one of your favorite units to work with.

🧵 Start your HRT journey with Dilly Dally Quilt or try one of my other patterns featuring this block style.