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Box pleat curtain tutorial.
Press all the pleats flat with an iron creating a 3 inch pleat so that the seam is behind the exact center of the pleat.
For my curtain i only wanted 1 pleat.
Return leading edge 4 for sewing the sides.
For each pleat you need to add 8 inches of fabric.
If you are mounting your curtain on a 1 4 board you need to add 5 for the ends of the board and 8 for the pleat in the middle.
6 30 it should say lining width face fabric width 6 inches instead of 3 inches.
I altered her tutorial just a bit and made my own box pleat curtain.
My window is 46 wide.
So this is how i did my math.
For the box pleat curtain example the window measured 50.
3 5 3 5 4 11.
As a starting place for the amount of fabric needed for the pleats you can multiply the distance you want the curtain panel to cover by about 2 or 3 depending on how full you want the curtains.
She does a great job describing how to measure how much fabric you will need with the addition of the pleats hems etc.
My board was 42 wide.
Pin your pleats so they measure 8 inches and top stitch 8 inches down on both sides of each pleat making sure to back tack at the bottom.