Half Rectangle Triangle Tutorial (Updated May 2013)
This tutorial is for Half Rectangle Triangles or HRT’s. This will add another tool to your quilting toolbox and hopefully you will be able to create some fun modern quilts using the HRT. When this tutorial was first posted it didn’t have instruction for “squaring up” these blocks and some of you were having a bit of trouble with it. This updated tutorial includes not only instructions for “squaring up” but, also it adds an extra step so that when you square up your HRT you will only have to trim it a little.
This tutorial will result in 4.5 x 6.5″ final block size so that you can easily follow along to learn this technique but, ANY SIZE rectangle will work as long as you use the same size rectangles. It has been tested on long skinny rectangles – 4.5 x 21″ – and after squaring up the final size was 4 x 20 3/4″ losing 1/2″ from one side and only 1/4″ from the other! Unfortunately, I don’t know the formula for what size block you’ll get relative to the starting dimensions of your block but, it should be 1/4″to 1/2″ smaller in either direction. When changing the dimension drastically, make a sample block to test it out.
2 – 5 x 7” pieces of fabric
Fabric Marking Pen/Pencil
Rotary Cutter & Mat
Index card (optional)
Directions (Left-Right HRT’s)
1. You will need a 1/2″ guide. If you have a ruler that is easy for you to see then use it. Otherwise you can make a guide from an index card. Simply mark 1/2″ from both edges of the corner of the index card.
2. Lay out both pieces of fabric.
3. Flip the left piece so the wrong side is facing up. Using the index card guide draw dots on the LOWER LEFT and UPPER RIGHT of the face down fabric on the left. And draw dots on the UPPER LEFT and LOWER RIGHT of the face up fabric. Since these dot will be well into your seam allowance, it doesn’t matter what type of marking pen that you use.
4. Draw a diagonal line that connects the dots on each piece of fabric.
5. Lift the face down piece and rotating to the left slightly place on top of the face up piece and match the diagonal lines.
6. Pin in place.
7. Using the diagonal line as a guide sew a seam 1/4″ on either side of the line.
8. Cut on diagonal line.
9. Open blocks and press.
10. And you have two HRT’s!
“Squaring” Up Your HRT
1. First you want to make sure your long edges are straight and parallel. As you can see, they should be pretty close and may just need to be trimmed a little.
2. Trim. Rotate and repeat on opposite side.
3. Rotate block 90 degrees so that it is laying on it’s side. Keeping your ruler lined up with the long side, slide ruler across the HRT until the 1/4″ intersection touches the diagonal line of your HRT.
5. Rotate and repeat on opposite end.
Directions for Opposite HRT (Right-Left HRT’s)
Note: Unlike Half Square Triangles, your diagonal line will be in the same orientation on both of your finished Half Rectangle Triangles no matter how you turn it. To make a set of Half Rectangle Triangles with a diagonal line in the opposite direction steps 3 and 5 will be different.
3. Flip the left piece so the right side is facing the cutting mat. Using the index card guide or the half inch intersection on your ruler draw dots on the UPPER LEFT and LOWER RIGHT of the face down fabric. And draw dots on the LOWER LEFT and UPPER RIGHT of the face up fabric.
4. Draw line through the dots on each of the pieces of fabric.
5. Lift the face down piece and rotating to the right slightly place on top of the face up piece and match the diagonal lines. (Not shown in pictures but it is essentially like step 5 above, you just rotate right instead of left.)
All other steps are the same.
As with Half Square Triangles, Half Rectangle Triangles can be used in countless arrangements to make fun and interesting quilts. Here’s another quilt using long skinny HRT’s. This one is called the Merge Quilt:
Note: This tutorial was written by MQG Board Member Latifah Saafir who blogs at The Quilt Engineer.