It’s October! This month we are making a ‘Half Square Triangle in a Half Square Triangle’ blocks. I don’t know if that is really a block name or not, but I thought it was a good name for this month’s block! 

We’re making 5 blocks total. You will need your background fabric and colors 2, 3, 4 and 5.                                        

You can download the PDF instructions here. 

Cutting: 

(1)  5” squares of Color 2.

(1)  5” squares of Color 3.

(1)  5” squares of Color 4.  

(1)  5” squares of Color 5.

(8)  5” squares of the background fabric.

For the 9 1/2” triangles, see diagram in the instructions before cutting.

(1)  9 1/2” triangle of Color 2

(1)  9 1/2” triangle of Color 3

(2)  9 1/2” triangles of Color 4

(1) 9 1/2” triangle of Color 5

We’ll start with the small HSTs: 

Step 1: Stack your 5” squares, (1) Color piece and (1) Background piece, right sides together.  

Step 2: Use a pen or chalk pencil to draw a line from corner to corner as a guide for your stitching. Then sew a ¼” seam on each side of your line. (This is a good spot to chain stitch again with the two squares)

Step 3: Cut along the line you drew in the previous step.

Step 4: Open the triangles and iron with seam allowances open. Do this for both halves.

Step 5: Trim the HSTs to 4 1/2”. 

Step 6: Take a background 5” square and cut it diagonally from corner to corner into two triangles.

Step 7: Sew one of the triangles to the HST you previously made. You will want to orient the background triangle along the side of the color half of the HST with a 1/4” tip overlapping as shown below. 

Step 8: Iron your seam allowances open.  

Step 9: Repeat Step 7 on the other side of the color triangle of the HST. 

Step 10: Iron your seam allowances open. This will leave you with a 1/4” seam allowance at the point of the HST as shown below. Your background triangles will be slightly larger than the HST block and that’s ok. Leave it this way for now. 

Now we will finish the block to make the larger HST half! 

Step 11: Cut your triangles. Since we don’t need (2) HST blocks of each color, we are starting with triangles instead of squares. Cut all the triangles with the (2) equal sides measuring 9 1/2“. 

Step 12:  Stack your color triangle with the piece triangle we previously pieced, right sides together.  Sew your seam allowance along the long, diagonal edge. Chain stitch opportunity! 

Step 13: Open the triangles and iron with seam allowances open. Repeat for each block.

Step 14: Trim all the blocks to 8 1/2“ squares. 

Step 15: Repeat each step until you have completed all 5 blocks! 

That’s it for this month! Five more blocks done! Only one more month to go!