Hitting the Blocks

Making Half-Square Triangle “Sandwiches”

Half-Square Triangles (HSTs) are exactly that—triangles that make up half a square. The most straight-forward way is to cut two triangles and sew them together. However, triangles have those annoying bias sides that stretch every which way. This is one way to avoid that problem:

Step 1. Cut your squares 1″ larger than your finished size. For example, if your finished patch is 2″, start with a 3″ square.

3″ 3″

Step 2. Place the 2 squares on top of each other, right side to right side.

Right Side Wrong side

Step 3. Draw a diagonal line from one corner to the opposite.

Step 4. Sew a scant ¼” seam on either side of the line.

Step 5. Cut the two sides apart along the diagonal line.

Step 6. Press open. Square up sides, using diagonal as guide.

Each 3″ square pairing yields two 2.5″ HSTs, without the stretching.

Folded-Corner Technique

Like the HST method, the folded-corner technique is a way around stretchy bias seams and the use of templates.

Step 1. Start with a larger square or rectangle (for example, 2.5″ x 6.5″) and a square of the smaller dimension (in this case, 2.5″ x 2.5″).

Step 2. Place the smaller square on a corner of the larger piece, right sides together, corners lined up.

Wrong side Right Side

Step 3. Draw a line from corner to corner and sew on line.
Trim ¼” from seam and press open.

This method yields a 2.5″ x 6.5″ strip without the use of templates or the aggravation of stretchy seams.