Seam allowance: ¼”. Unless you are sure that you have a ¼” seam, I suggest that you measure it. Cut two 1” strips of fabric and stitch them together. Press open and measure the width. It should be 1 ½”; if not, you need to adjust your seam.
Triangle in a square
This is a basic unit for lots of different star blocks and can also be used as standalone blocks.You’ll use one triangle and two corners, one Left and one Right.
Place one corner and the triangle right sides together, aligning the diagonal edges.
The short edge of the corner should look like this
and the other side look like this. Your ¼” seam shall start (or stop) at the arrow.
Stitch along the edge and press open; I don't trim the dog ear just yet.
Place the other corner the same way;
I use the dog ear to make sure that the overlap is right. The dog ears should not overlap fully.
Stitch the second seam and press open. Trim the dog ears. When pieced correctly, the finished unit should be a square.
Two corners can be stitched into a rectangle. You can use either two Rights or two lefts; these are Rights
Place them right sides together aligning the diagonal sides and so that the short sides align at the bottom on each side
Stitch along the diagonal edge, press and trim the dog ears.
The Spike rectangles will always be twice as high as wide. Spikes make great borders,
and fun, graphic quilts.
When joining two triangles, one needs to point upwards, and the other downwards
Align the diagonal edges so that you get a overlap at both ends as described under ”Triangle in a square” above and stitch along the diagonal edge.
Open up and press. Continue to add triangles the same way to make
or rows for a quilt