The nine patch block is a cornerstone block for so many quilt blocks, which is why it's a great block for beginners to master. Once you really see the fundamentals in this block, you can superimpose it over a more complicated block to reach your quilt math.
Let's break this block down. It's obvious to see the quilt block is made up of 3 columns with 3 rows. 3 x 3 = 9, thus the Nine Patch block. The number 3 is the key to understanding the math of this block. All 9 patches will be exactly the same. So let's figure out the numbers for a few standard block sizes. Let's look a 12-inch block first.
As with the 4 patch block which I talked about in a previous blog post, we're going to find the number of columns and rows - both 3 with this block; that's the divisor for this block. Divisor is the number that divides another number, in this case the finished block size of 12 inches, into equal parts.
You'll divide the finished size block by 3 to get both length and width of each block.
12 ÷ 3 = 4
The finished size of each individual block will be 4 inches; don't forget to add a quarter inch to each side for the seam allowance, thus making the unfinished piece size 4½ inches square. Cut nine 4½ inch pieces to create a 12 inch finished Nine Patch Block.
Below is the math for a few other popular sizes. You'll see the block with the easier math are those that are divisible by 3. Some of the decimals or fractions can get a bit scary, so I recommend to round up to the nearest "easy" number. You'll see this in the last column. Just a tip when choosing block size for this block.
Here's a quick tutorial for a 12 inch finished nine patch!
Select 3 fabrics: a light, medium and dark. Cutting instructions:
light fabric: cut 4 4½ inch squares
medium fabric: cut 4 4½ inch squares
dark fabric: cut 1 4½ inch square
Layout the block as seen here. The four light color squares are in the corners; the dark is in middle, and the medium fabric fills in the rest.
We're going to sew each row of blocks together first. (see below)
Rows 1 and 3: sew a light fabric square to either side of a medium fabric square
Row 2: sew a medium fabric square to either side of the dark fabric square
Press seams according to preference. I like to alternate the direction I press per each row so that the seams will nest together nicely when I go to sew the completed rows to each other.
Sew Row 1 to Row 2; use a pin, or watch the seams to ensure that they match together, then press.
Sew Row 3 to the top unit; press.
Done!
Here's a quick mock up of a Nine Patch Quilt! I'm using Decostitch Elements by AGF Studio.
Thanks for doing a little quilt math with me today! I hope you enjoyed it! I'm heading back to the quilt lab; cya next time!
Cynthia