I played with my graph paper this morning and worked out the measurements to make a keyboard. I wouldn't like to stitch anything narrower than 1/4" strip though.
The black keys were cut 1 1/2" wide x 4" long
The thicker ivory keys between the black were cut at 1 1/4" wide x 4" long
The thinner ivory strips were cut at 3/4" x 4" long
The whiter edge strips were cut 1 3/4" wide x 3" long
This is all including a 1/4" seam allowance.
I cut a small piece of ice-cream lid and used double sided tape on my machine to ensure a constant 1/4" seam - it worked!!! surprise surprise!!
I pressed the ivory seams towards the black. I pressed the ivory pair seams open. I was able to match the seams when I stitched the black/ivory strip to the ivory/ivory strip.
I'm so pleased - it worked the way I could see it in my head!!!
I had to share!
black and ivory pieces ready to stitch
stitched and pressed - now to match the seams
keyboard - ready to play!