From the retreat: curved piecing

At the retreat I more or less completed the Roundabout kit blocks from  Karla Alexander 's workshop and took pictures of the curved method placing the convex shape on top and easing in fullness underneath with a sweep of finger or hand while using another finger on top to set the edges together.

A completed block apart from slimming down the sides.

Centres of shapes marked by folding then secured with a pin.

I secured the end of the seam not with a pin but with a
few stitches, making sure the sides were straight on top
of each other,

Now sewing from the start with the convex shape on top. A seam guide helps.

Seam sewn

and pressed. The sides form a straight line.

From the front