Today in the Exploring the Basics blog series, Tammy and I are chatting about the Half Rectangle Triangle. This is another one of those units with many names. Some call it half long triangles, half rec, split rec…. so many names!
Let’s explore a few ways to make the unit.
Traditional Piecing the Half Rectangle Triangle
To make this block, you can cut 2 rectangles, layer them together with both rectangles rights sides up and cut corner to corner along the diagonal line.
Layer the cut triangles right sides together and offset the points by ¼”. Sew them together, press and trim to size.
You can also cut the same triangles using a triangle ruler, such at the Triangle Recs tool or the Creative Grids Perfect Rectangle rulers. That way you don’t have to wonder how much to offset, just line up the angled cuts!
Making 2 at Once!
In this next method, it makes 2 blocks at once! Who doesn’t love to save a little time! First a little quilt math.
The math for these is to determine how big you want your finished rectangles to be. Often, they are a 1:2 ratio so if the block is 3″ wide it will be 6″ long.
Once you know the finished size, add 1″ to the short side and 2″ to the long side. For a 3″ x 6″ finished rectangle, I would cut a rectangle 4″ x 8″.
Now….. I like a little wiggle room so I would probably add another ¼” and cut them 4 ¼” x 8 ¼”.
To keep all the quilt math in one place, the other size you need to know is what size to trim the units. That is the finished size plus ½” so for my 3″ x 6″ rectangles, after sewing I would trim to 3 ½” x 6 ½”. More on trimming below.
Marking and Sewing
Mark a diagonal line corner to corner on the lighter rectangle. Or, if you are like me and like to make the sewing lines, mark 2 sewing lines ¼” away from the diagonal line. Just like you would do for a HST unit!
Here is a tricky part; position the rectangles right sides together with the top rectangle at an angle to the bottom rectangle. If you drew your line(s) from top left to bottom right, it would look like this.
If you drew your line(s) top right to bottom left, it would look like this.
Sew ¼” from the diagonal line on both sides and cut along the diagonal line. Press the seam open or to one side.
This is another tricky part but once you get the hang to it, it’s not hard!
I need to trim my rectangle to 3 ½” x 6 ½”. To give you an idea of how big these are starting at, I oversized my pieces by ½”. (A little much, but easier to show the trimming.)
Trim so that the corner points are ⅛” in from the corner- NOT right in the corner. While there are some specialty rulers for trimming that are helpful, I don’t have one. Though, if I was making a bunch of these, I would probably get one, maybe the Bloc_Loc one.
Place your ruler so the lines for the 3 ½” and 6 ½” are ⅛” away from the diagonal seam.
Here is a close up of the bottom corner of the ruler. See where I drew the tiny white line? That was just to show the ⅛”.
Offset at the top corner.
My ruler is 6 ½” wide so it makes easy to trim 3 sides at once but for a smaller unit, I would trim 2 sides.
Then rotate the unit, line up the lines for the correct size and trim the other 2 sides.
The trick is lining up the ruler for the first cut. I had to move it around until I found the spot so that I was ⅛” away at both corners!
Wouldn’t these make great star points?
Below are 2 rectangles sewn together- see how by offsetting the point at the corners my points will be right at the ¼” when all sewn together? I won’t lose my points!
Click here to head over to Tammy’s post and see how she uses the Studio 180 ruler to make her half rectangle triangle units- or as they call them, split rec blocks!
I update an earlier post on organizing my quilt studio with a link to another great blog post! Click here to see the updated post and then head over the other blog. I think you will like all of Ali’s ideas!