Big O Quilt Block Instructions

A Partial Seams Patchwork Design

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Skill Level: Beginner

Our Big O quilt block is the second block in our series on the partial seams technique (the first is 'Bright Hopes').

This time we add connector corners at the end to change the look and create the 'O'.

If you'd prefer to skip partial seams, you can easily piece this block using the Shoofly block pattern. Simply change the color placement.

Big O looks terrific paired with an 'X' block, like the 'Cotton Boll', for a 'kisses and hugs' quilt. Perfect for a young child or new baby.

Let's get started!

The Big O quilt block tutorial

General Instructions

Seam allowances (SA) are all 1/4" unless otherwise noted.

Pressing: First press with the patches in the closed position to set the seams, melding the thread into the fabric. Then open the patches and press with the SA towards the dark.

Pressing instructions are highlighted in yellow to make them easy to find.

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Click the images below to see the full collection and any commercial and/or free patterns that showcase them (for inspiration, of course!)

Step 1: Cutting for a Big O block

Big O quilt block designBig O design

Sample Size: 6" finished / 6½" unfinished

Grid: 3x3

Design Type: Even 9-patch, Partial seams

Though I've shown this as a two color block, there's no reason you couldn't make it scrappy.

Just keep the color values close together in your light and dark fabric groupings.

The choice is up to you as the designer!

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Cutting Chart for a
Big O Quilt Block

~ Traditional Piecing ~

Patch Fabric Qty Finished Block Size
3” 4½” 6” 9” 12”
1, 3 Light 5 1½” x 1½” 2”x2” 2½” x 2½” 3½” x 3½” 4½” x 4½”
2 Dark 4 1½” x 2½” 2” x 3½” 2½” x 4½” 3½” x 6½” 4½” x 8½”
Unfinished Block Size 3½” 4½” 6½” 9½” 12½”
Grid Size 1” 1½” 2” 3” 4”
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Step 2: Assembling the Big O quilt block

Unlike the Bright Hopes quilt block (the first in our partial seams series), this time the rectangles are added around the center square in a counter-clockwise fashion.

With right sides together (RST), align three sides of a #1 square with a #2 rectangle.  We'll be stitching just half of the bottom side of this pair for now.

Align a #1 and #2 with right sides togetherStitch a 1/4" seam from approximately the middle (short black line above) to the end of the patches.

Using the photo below as a guide, stitch on the bottom edge from the middle of #1 (the black arrow) to the edge. I do not backstitch at the start. These initial stitches are secured when you overlap your stitching at the end of adding the rectangles to the center square.

Sew from the middle of #1 to the edge

Here you can see my red stitching...

The first seam is partially sewn

Press.

With RST, align the edges of the pieced #1/#2 with another #2. Stitch from edge to edge. No more partial seams to stitch until the last of the rectangles is added.

Add the second #2 rectangleThe black arrow points to the first partial seam in red.

After sewing and pressing two #2s, the unit looks like this...

Three patches sewn together

Add the last two #2s in the same manner. Remember to press after each.

At this point your Big O looks like this.

One partial seam to attach the last rectangle

All that's left is to sew the remainder of the first #2. Use pins if it helps.

Sew, remembering to overlap your stitches by a 1/4" or so (the black arrow).

Stitch remainder of your first seam

Press.

To finish the Big O, we'll use the connector corners technique.

Draw a diagonal line on the backside of all four #3 squares.

With RST, align one square in a corner and stitch on the line (black arrow). Notice I've switched to my open toe applique foot. It's easier to see the line and where my needle is going!

Repeat for the remaining corners.

Trim the SA a 1/4" from your stitching, on the side closest to each corner. Below you can see the process.

Finish by pressing just like in the two lower corners.

That's it! Your Big O Quilt Block is finished and ready for your quilt!

A finished Big O quilt block

Other blocks that use Partial Seams piecing

Once you learn a new technique, it's a good thing to practice it a bit. That helps commit it to memory.

Below are more blocks on this site that use this technique. Click the image to go to the directions to make it.

Bright Hopes quilt block tutorial Double Star quilt block tutorial Night Vision quilt block

If you need a different size block...

For a list of all the quilt block patterns on this site, start here.

If you know the name of the block, you can shorten your search by using these alphabetical links:

A-D

E-M

N-Z

Click here if you're looking for blocks with at least some paper piecing.

Click here if you're looking for the basic building blocks of quilting, i.e. Flying Geese, half square triangles, quarter square triangles, etc., along with several techniques to make each.

And finally, use these links to find blocks in these finished sizes:

For even more blocks to make...

Click here to learn about my favorite quilt book resources that inspire my patchwork designs.

For you, are quilt block patterns like potato chips?

You can't have just one?!!

Check the fantastic resources I rely on for the majority of the quilt block designs you see on this website. 

To see if they're worthy of a spot in YOUR quilting library, read about them HERE.

NOTE: All the attribution and alternate names shared in the Free Quilt Block Patterns Library came from these four resources.

This article was printed from Generations-Quilt-Patterns.com

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