I didn't want to applique 8 little melons so I came up with a different way. I think it worked pretty well.
Cut a 6" square out of background fabric.
Print or trace the block diagram onto the dull side of freezer paper. Cut out as below and iron to the right side of the background fabric square. Cut out the inner section as in the photo. Clip the sharp inside corners.
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Cut a 5" x 5" square out of main block fabric. Place it right side up on the table. Center the background fabric section right side up on top of it. Baste securely through all layers.
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Turning the seam allowance under, reverse applique the center shape.
Remove the freezer paper and press. Cut away the excess fabric from the back of the block.
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Reuse the freezer paper you just used or trace a new block diagram onto the dull side of freezer paper. Cut out the center circle and corner quarter circles.
Out of main block fabric, cut a 6" x 6" square.
Iron the freezer paper onto the right side of the fabric square and cut out as below.
Clip all the curves every 1/4" or so.
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Place this block section right side up on top of the first section you made, carefully centering it.
Baste securely through all layers.
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Turning the seam allowances under, reverse applique the circle and corners.
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Trim the block to 5" x 5", remove the freezer paper and press.