Half Square Triangle Stencil 2in
Sunday's Best Quiltworks

Half Square Triangle Stencil 2in

Regular price $10.00 $8.00 Unit price per

This handy HST stencil allows you to make HST units that are both quick and accurate. Yah!

 Check out the demonstration on YouTube

The 1”, 1-1/2”, 2”. And 2-1/2” make 32 HST’s in only 15 minutes, and require no squaring up.

Simply trim away the dog ears and you’re done!

The stencils indicate the FINISHED SIZE of the unit after it is sewn in.

Example: a 2” finished HST should measure 2-1/2” before it is sewn. Accuracy depends on carefully sewing ironing and cutting on the designated lines.

Steps to Create perfect Half Square Triangles

1 - Determine the number of HSTs you wish to make. Following the cutting directions, limits wasted fabric to 1/4” around the perimeter. 

2 - Layer two contrasting colors of fabric and cut to fit the size of the stencil.

3 - Pin the stencil to the lightest of the two fabrics using the small round pinholes. 

4 - Notice the black and red lines in the diagram. The RED lines are SEWING LINES. The BLACK lines are CUTTING LINES. Use a water washable marker to mark the BLACK lines and a heat erasable marker to mark the RED lines.

5 - Layer fabrics right sides together and pin to prevent shifting as you sew.

6 - Make a continuous stitch on the red lines and leave your needle down as you turn at the corners.

7 - Remove pins and iron. Heat will remove the marks behind the sewing lines.

8 -Place the sewn unit on a cutting mat that you can turn. All cutting is done before the unit is removed from the mat. (1) Cutaway outside perimeters. (2) Cut straight lines in one direction. (3) Turn mat & cut straight lines in the other direction. (4). Turn mat and cut all diagonal lines in one direction. (5) Turn mat & cut all diagonal lines in the other direction. 

9 - HST units are now pressed from the front, pushing the seam allowance toward the darkest fabric.

Our Half-Square Triangle Stencils in sizes 1", 1 1/2", 2" and 2 1/2" each make 32 FINISHED half-square triangles.

Our 3" and 3 1/2" Half-Square Triangle stencils make 18 FINISHED half-square triangles. Our 4" and 4 1/2" Half-Square Triangle stencils make 12 FINISHED half-square triangles.


We Recommend using any Water Washable Marker and/or Frixion Highlighter, and an OLFA Spinning Square Cutting Mat 17 inch.