Sewing Pinwheels

In my last post, I showed you how to cut and prepare the pieces you'll
 need to make this Pinwheel Coaster.  Now it's time to sew!

We'll be using a precise 1/4" seam allowance, which is typical for most piecework.  Use a seam gauge to find a "landmark" on your presser foot to make this easier.

Make sure your fabric pairs are aligned at the corners.  Then sew a straight seam 1/4" on both sides of the pencil line.  Give your pairs a quick press, then cut your sewn pieces on the pencil line.  You'll have two squares made up of two triangles.  These are called "half-square triangles."  Press your half square triangles closed to set the seam, then open them up and press both seam allowances toward the darker fabric.  Use small sharp scissors to clip the "dog ears" off at the end of each seam.

Lay out all four of your half square triangles, arranging them to make a pinwheel shape.  Sew the left two half square triangles together, and then the right-hand pair.  Press the seam allowances toward the darker fabric.  Then sew the final center seam to make your pinwheel.  Press the seam allowances to one side.  Use your ruler, rotary cutter, and mat to square your block up to a perfect 5 1/2".

Lay your backing square face up on your batting square, and your pinwheel face down on top of the backing square.  Make sure everything is lined up at the corners.  Sew around three sides with a 1/4" seam allowance.  Trim the batting very close to the stitching line, clip the sewn corners diagonally, and turn  your coaster right side out.  Turn down 1/4" at the open edge, and use an invisible stitch to sew the opening closed.  Give your coaster a good press.  You can machine quilt your coaster, too.  Use a walking foot on your machine to keep it flat and square.  Great job!