Siodach

Firstly, thank you to Wavewatcher for the perfect title for my quilt - Movie Stars!



Happy to help, I've taken a few photos using scraps to show what I did.

My block finished at 12.5 inches before any sashing.

For each block I cut 2 rectangles of black fabric measuring 16.5 x 4.5 inches.

Place two rectangles together with BOTH face-up, and measure and mark 1 inch in from the top left corner and also the bottom right.

[ATTACH=CONFIG]509046[/ATTACH]

[ATTACH=CONFIG]509047[/ATTACH]

Join these two marks and cut along the line. This will give you 4 identical almost-triangles.
[ATTACH=CONFIG]509048[/ATTACH]

This shows how they will be aligned with your centre square. It is important to line up the wider right-angle of the sashing with the corner of your square.
[ATTACH=CONFIG]509049[/ATTACH]

Face to face, the right angle corners should match.
[ATTACH=CONFIG]509050[/ATTACH]

Sew a seam from the wider corner along towards the narrow corner. Stop about an inch from the end of your square - this seam will be finished after you have attached all four sides.
[ATTACH=CONFIG]509052[/ATTACH]

Press open the seam, and attach the remaining sides in the order indicated. Your right angle corners will align, and the narrow end of your sashing will overlap the previous wide end.
[ATTACH=CONFIG]509051[/ATTACH]

After sewing on all four sides, you can go back and complete your first partial-seam.

This will complete one block. You will need six blocks like this.

To make your other six blocks wiggle the opposite way, you need to place your rectangles FACE - DOWN before marking your 1 inch indents.

I found I had about half an inch to trim to square off the narrow ends of the sashing.

Sorry this got a bit long, but hopefully it's clear enough to understand .

Edited to add: doing this gives you blocks where all the outside edges are cut on the bias, so please handle with care . Starch is your friend .

Cheers, K