As promised, here is a pictorial class in free form curvy piecing. This technique seems very complex, but give it a go with some scrap first and you'll soon see it's not nearly as hard as it looks!
First up, I have four pieces of contrasting fabric of varying widths and lengths. You can make them all the same size if you like, but remember that they will shrink up quite a lot with piecing and will not remain the same length either.
Take two pieces of fabric, an original and an insert. Next, lay the piece you want to insert (the white and orange spots) underneath the original piece of fabric (the pink). Make sure that the insert piece is a fair way underneath the original piece or you will not be able to cut a very deep curve.
Using your rotary cutter, freehand cut a gentle curve through both layers of fabric, making sure that you get both layers and not just one. Do not make the curve too deep or it will be too hard to piece. This is not as hard as it looks, just jump in and cut and you will see what I mean!
Take the piece of orange fabric away from underneath the pink, and the pink from on top of the orange, leaving the two pieces you are going to sew together. Trim the orange piece to be level with the top of the pink fabric. The bottom edge doesn't matter so much.
Turn the piece of orange fabric over onto the pink fabric so they are right sides together, and align the curves at the top edges. Sew the pieces of fabric together very slowly, stopping to adjust so that you are sewing a straight line all the time and NOT stretching or pulling at the fabrics in any way. If you think you are going to sew a pleat, stop, lift the foot, re-arrange the fabric and keep sewing. You should always be sewing a straight line ahead of you even though in the overall picture you are sewing a curve. Go slowly and it won't seem so complex!
Press the seam towards the orange, inserted piece of fabric.
Repeat this with the next colour by laying the fabric to be added (the green) under the last piece (the orange).
Cut your next curve and remove the green fabric behind the orange, and the orange on top of the green.
Sew and press the seam towards the inserted fabric (the green).
Keep going until you have made the piece as long as you wish. If you want to make a panel of another fabric inside what you have already pieced, continue as follows:
Place a larger piece of fabric underneath the panel you have pieced and cut as before. This is the steepest curve I have cut in this tutorial and I wouldn't recommend cutting a curve any steeper than this or it will be difficult to make it lie flat after it has been pieced. Set the piece of fabric you cut away aside carefully.
Piece this panel in as before and press the seam.
Take the piece of fabric you set aside and lay the edge of it underneath to cut away as before. Cut a gentle curve so that you do not have to take too much off the right hand piece.
Sew and press.
Lay another piece of fabric under the curved edge that is left. Using the rotary again, cut along the edge of the curve carefully and remove the piece of pink fabric left behind.
Sew, press and trim to be square!
This method is great for lots of things, including wavy borders and scrap quilts. I most recently used this technique when I was at the AQC. The class I took involved designing an art quilt based around trees, and I wanted to make something representing a gum tree I pass every morning while I'm walking my dog.
The tree has a twisted trunk and when the sun comes up, the pink and gold glimmers on the smooth white bark of of the trunk. In the summer, the dark bark sheds and leaves behind another smooth, whiter layer underneath.
I made several panels of curved piecing and pieced them together with larger, solid blocks of fabric.
I am currently playing with the bark and leaves to create the effect I want.
So there you go! Freehand curved piecing, which I must point out is very different to the curved piecing you would want to do on a Drunkard's Path block or something of that sort which requires precision.
Get out those rotary cutters, throw your rulers to the side and have a go!