32 HSTs At Once!
In this video, Bob demonstrates how to make 32 half-square triangles (HSTs) at once using a creative twist: a colorful nine-patch block instead of plain fabric to add extra variety and visual interest. He explains how to layer two 14-inch squares right sides together, mark a grid of straight and diagonal lines, and sew quarter-inch seams on both sides of the diagonals. After stitching, Bob cuts along the marked lines to reveal perfectly sized 3-inch HSTs, each featuring multiple fabric combinations. He also showcases the Fiskars Rotating Cutting Mat (13"), which makes trimming the pieces much easier. The tutorial ends with Bob encouraging viewers to try this fun technique, watch more of his quilt block videos on the Sewing Parts Online YouTube channel, and, as always, happy sewing.
We’re making 32 half-square triangles at once, and these aren’t your regular HSTs. Take a look from the overhead camera — these are multi-fabric half-square triangles, and they’re beautiful. The reason they look this way is because I used a nine-patch to make them. You don’t have to do that, but it adds so much color and variety to the final result.
To start, I took two pieces of fabric and placed them right sides together. Each square measures 14 inches. Instead of using a plain piece of fabric, I made a colorful nine-patch out of 5-inch charms, which finished at 14 inches. That’s why I chose this size for the demo. The finished half-square triangles will measure 3 inches each.
Once you’ve got your fabric squares ready, place them right sides together. On the back, you’ll draw a few lines to guide your stitching. Draw one vertical line down the center and one horizontal line across the middle. Then, add lines halfway between those, both vertically and horizontally. Finally, draw a large “X” corner to corner, and then connect the center of each side diagonally. The diagonal lines are the most important — those are the ones you’ll sew along. Stitch a quarter-inch seam on both sides of every diagonal line.
After you’ve stitched everything, every line you drew — straight or diagonal — becomes a cutting line. To make the process easier, first cut the block in half vertically and horizontally so you have four equal sections. Then, treat each one as its own piece and cut along the remaining lines.
This is where my favorite tool comes in: the Fiskars Rotating Cutting Mat, 13 inches. It makes trimming so much easier. Just place one of your sections on the mat, line up your ruler, and cut along each marked line, rotating the mat as you go.
When you’re finished, you’ll have 32 perfect half-square triangles — each with a mix of colors and prints from the original nine-patch. They’re fun, fast, and full of variety. I absolutely love this technique, and I’ll be using these blocks in an upcoming quilt project.
If you’d like to watch more of my quilt block tutorials, visit our YouTube channel at Sewing Parts Online. Don’t forget to like, subscribe, and happy sewing
