Square in a Square Unit

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Image of Square in a Square Block
Square in a Square Block Exploded
Square in a Square Block Exploded


How to make a Square in a Square Unit

(Using the Quick Corner Method)

Draw a diagonal line on the wrong side of each of your smaller squares. (Figure 1)

Image of patch with line on diagonal
Figure 1


With right sides together, align one marked smaller square with one edge of the large base square and another in the opposite corner of the base square as shown in Figure 2. Stitch one thread width to the outside of the diagonal lines.

Marking and Patch arrangement for sewing a SNS unit using the Quick Corner Method
Figure 2

Cut 1/4″ outside the stitching lines as shown in Figure 3. Flip the triangles open and press the seam allowance toward the triangle.  (The exploded image at the top of this page shows arrows indicating which direction you should press. 

Trimmed corner on SNS Unit
Figure 3

Repeat steps 2 and 3 for the other corners of your base square to complete the unit.

The formula:

If you don't see your finished size block in the chart below, here is the formula for how to determine the size pieces you need.

For the large square:

Add 1/2" to the finished size.

(If you want a 2.5" finished size, then you need to cut a large square that is 2.5" + .5" = 3")

For the small squares:

Divide the finished size of your block in half.  
(If your finished size is 2.5", then half would be 1.25".)  

Add 1/2" to that to determine the size of your small squares.

(In our example, we would add 1.25" + .5" to result in 1.75" squares.)

Quick Corner Method
for Making Square in a Square Units

(Makes 1 Unit)

Finished Size of SNS UnitLarge Square Base
(Cut 1 square the size indicated below)
Corner Triangle Units
(Cut 4 squares the size indicated below)