SewPrompted2016 ~ Triangles

Triangles is this week's SewPrompted 2016 word on Instagram!

I'm starting off this week with a post for Kerry Goulder's (@kidgiddy) #sewprompted2016.

Triangles are everywhere!

I love triangles. These are examples of quilts that I have designed over the years. Triangles play an important role in almost every quilt that I make.


PDG173 Sonoma Topper

PDG421Garden Party

PDG418 Crossroads

This is a quick tutorial on making Half-Square Triangle Blocks (HST for short).

Exact: The traditional "exact" formula for cutting a square to make a Half-Square Triangle Block is:   Finished size + 7/8".
For example, if your HST is supposed to be 2" finished; cut the square 2-7/8".

Oversized: If you prefer to make the HST units larger and then trim them to size, add 1" to the finished size.
The units will be a little bigger than they need to be and you trim them down to the right size. This has become my favorite method.

Here we go....

Method 1:  Sew Before You Cut

Draw a line from corner to corner on lighter fabric.

Draw a line from corner to corner on the lighter fabric.

Sew a scant 1/4" from both sides of the line.  Scant means just a thread less than a full 1/4".

Sew a scant 1/4

Cut apart on drawn line to get two HST blocks!  Press to the darker fabric and trim to size as needed.

Cut apart on drawn line to get two HST units.

Two HST units


Method 2:  No Math Method

1.  If you are using 3" squares to make a block like this one and need to make an HST that will fit, simply use two 3" squares; a light and a dark.

Four-Patch-with HST units

2.  Place fabrics right sides together and draw a line from corner to corner on the lighter fabric.

Draw a line from corner to corner on the lighter fabric.


3.  Draw a SECOND line 1/2" away - this will give you a bonus HST that is 1" smaller than the large HST.

Draw a line from corner to corner.  Draw ANOTHER line 1/2
4.  Sew ON THE LINES, actually just a hair inside would be even better.

Sew on each line.

5.  Cut apart between sewn lines and press to the darker fabric.

Cut apart between sewn lines.

6.  The large HST will fit perfectly with the plain 3" squares in the four patch block above.

Big and Little triangles from one square.  Save the litte ones for another scrappy project.

7.  The BONUS block can be squared up to 2" and saved for a scrappy project.

Taking this one step further (and better!), there is a tool that was created just for this method!


The Folded Corner Clipper makes Half square Triangle blocks by allowing you to trim the corner first.
You can use it for lots of other units too. Here's a LINK to the Prairie Sky Quilting blog with more information.

Happy Quilting!








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