Eight-at-a-Time Half-Square Triangles
Before You Begin
Skill Level: Intermediate
Technique: Traditional Piecing
Time Required: About 15 minutes
Tools Needed: Sewing machine, rotary cutter, quilting ruler, marking pencil, iron, two fabric squares
Introduction
If your pattern calls for a large number of half-square triangles, the eight-at-a-time method can save a tremendous amount of time. Instead of sewing individual units, you'll create eight matching HSTs from one pair of fabric squares.
This method works especially well when your quilt uses multiple identical HSTs. Just like with the two-at-a-time method, I recommend trimming each unit after pressing for the best accuracy.
Step 1 – Prepare the Squares
PHOTO
Place one light square and one dark square right sides together.
Using a removable marking tool, draw two diagonal lines from corner to corner, creating an "X" across the square.
Step 2 – Sew Around the Diagonals
PHOTO
Using a ¼" seam allowance, sew on both sides of each diagonal line.
When you're finished, you'll have eight seams surrounding the two marked lines.
Step 3 – Make the First Cuts
PHOTO
Using your rotary cutter and ruler, cut the square in half vertically and horizontally.
You should now have four smaller squares.
Step 4 – Cut Along the Diagonals
PHOTO
Cut each smaller square along the marked diagonal line.
As the pieces separate, you'll reveal eight half-square triangles.
Step 5 – Press and Trim
PHOTO
Press each HST toward the darker fabric unless your pattern specifies otherwise.
Trim every unit to the unfinished size listed in your pattern using a quilting ruler aligned with the diagonal seam.
My Tip
This method is one of my favorites when making quilts with repeated units. I often sew several large square pairs first, then cut, press, and trim everything assembly-line style. Working in batches makes the process surprisingly fast.
Frequently Asked Questions
-
Both methods can produce excellent results. Eight-at-a-time simply creates more units at once, making it a great choice when you need quantity.
-
Yes. Trimming ensures every unit finishes at the same size and improves the accuracy of your finished blocks.
-
Generally, no. Because the units are cut from one large square pair, directional prints often end up facing different directions. If fabric orientation matters, another HST method may be a better choice.
Continue Learning
Accurate Quarter-Inch Seam Allowance
Two-at-a-Time Half-Square Triangles
Square-in-a-Square
No-Waste Flying Geese
