Arithmetic Block – this is a FREE tutorial, enjoy and share photos at http://www.flickr.com/groups/2306478@N20/ but please do not charge for any patterns which use this tutorial or any photos!
Finished Block size 12 inches, unfinished 12.5 inches:
Fabric required: 4 fat quarters, two lighter value and two darker values. This block can be made from 4 fat eighths (9″x11″ pieces of fabric) if you cut carefully, backgrounds use the most fabric. Numbers in () indicate the # of each to be rotary cut. I used fabric from Everything Blue by Clothworks with some additional solids.
Light Background Fabric: Add – (5) 3″ E squares, cut one square into (4) 1.5″ C squares, Multiply – (8) 1.75″ J squares, (2) 1.5″x6.5″ D rectangles, (2) 1.5″x4.5″ A rectangles
Dark Background Fabric: Subtract – (2) 1.5″X6.5″ D rectangles, (2) 3″x4.5″ F rectangles, Divide – (2) 1.5″ C squares, (2) 3″x6.5″ G rectangles
Dark (+ Add and x Multiply Symbols): (2) 1.5″x2″ B rectangles, (1) 1.5″x4.5″ A rectangle, (4) 2.5″ K squares
Light (- Subtract and ÷ Divide Symbols): (2) 1.5″x4.5″ A rectangles, (2) appliqué circles
Arithmetic Block Diagram
All seams are 1/4″ seams pressed open unless otherwise noted. See diagram below for appliqué pattern and seam pressing. This is usually as far as I go on a pattern and then I just make up my own construction, pressing seams after I sew them, so do what works best for you!
(1) Add: Sew B to C and then attach E squares to each side, sew C squares to each end of the A rectangle and then sew the larger rectangles to each side of the narrow center one.
(2) Subtract: Sew each F rectangle to either side of A, and then attach narrow D rectangles
(3) Multiply: Place J squares over opposite corner of K squares, sew down the diagonal (mark with a pencil if needed), trim seams to scant 1/4 ” and press open gently. When attaching these squares to each other, I pressed all seams open until attaching the A and D rectangles, when I pressed away from the center:
(4) Divide: Sew C squares to ends of A rectangle, then attach large H rectangles. I wait to add appliqué (see step 6) until the entire block is pieced to help with placement.
(5) Trim inside edges of blocks if needed before sewing Add to Subtract and Divide to Multiply, press seams toward Subtract block and Divide block, sew remaining units together and press final horizontal seam open.
(6) Trace circles from thread spool end onto the fabric for the Divide (÷) symbol (see my photos for tracing and placement)
Trace around a thread spool end, keeping the pen vertical while you trace to keep the circle even and broad. I will cut around the line and turn under a scant 1/4″ as I go, use the alignment with the bottom “Add” seam above the top circle to center your first circle.
If you are new to hand appliqué, be patient with yourself and go back and look at my circles… they are definitely not perfect, but they are good enough! I bring up the needle as shown, right in the center of where I’ve finger-pressed the seam under, take one invisible backstitch and then come up again from underneath, right at the seam edge. I am right-handed so I sew from right to left so I can see my stitches. I take little 1/8″ or smaller stitches, and try to keep turning the seam under every two to three stitches. The biggest cause of stretching or shrinking circles seems to come from not pinning, or pressing the block as you go. Some people take invisible stitches and some take tiny stitches over the edge of the pressed seam, I kind of do both depending on how my seam feels, just matching my thread and keeping stitches small. You can press over pins, but press the block and the pinned circle before stitching, especially if you stop and start again later after it has been folded or put away. I hope you like my first tutorial!