Monday, April 14, 2014

Spring Sampler - Square in Square Block Tutorial

Sponsored by Connecting Threads

Welcome back!  Last week we chatted about fabric requirements and how to choose your fabric palette for our Spring Sampler Quilts.  More information on the project is available here.

Spring Sampler - Wall-hanging

Spring Sampler - Lap-Size
This week, while everyone is pulling their fabric choices together - don't forget to share your pictures in our linky party - we're posting tutorials for a few of the blocks we'll be using in our tutorial.  We've already shared how to put together Flying Geese Blocks, and today we're talking about the Square-in-Square block.

For those interested in just putting the block together, I'm going over the construction part first!  If you're interested in the mechanics of the block and the math behind it ... read on! :)

Assembling the Block

To make a Square-in-Square block, you'll need one center square, and four outer triangles.

1.  Finger-press the a crease to mark the center along the left and right edges of the square.  Finger-press a crease to mark the center on the longest side of two of the triangles.

2.  With fabric right-sides-together, pin a triangle to the left side of the center square, making sure to match up the crease marks.  Repeat to pin a second triangle to the right side.

3.  Stitch along the edge of both sides, using a scant 1/4" stitch.  Press seams towards the triangles.

4.  Finger-press a crease to mark the middle of the top and bottom edges of the center block, and the long edges of the two remaining triangles.

5.  Pin right sides together, matching the crease marks, and stitch. 

6.  Press seams towards the triangle.

7.  Because cutting measurements are always rounded up (see below), the block will most likely be a little larger than required.  Trim and square the block down to the needed size, making sure to maintain those 1/4" seams at the edge of the block.

8.  Tah-Dah!  You're finished!

The Mechanics ...

I design most of my quilts in Electric Quilt 6 (EQ), but one of the issues I have with the software is that for the Square-In-Square block, they always use a square cut diagonally in quarters for the outer triangles.

The problem with using this method is that it creates a triangle with two bias sides.

And once these triangles are attached to the center square, the entire block now has bias edges.

Bias edges stretch and distort very, very easily ... and that becomes a problem if you have to rip seams out, if you're not super careful while pressing, or even if you handle the block too much.  Since these blocks are at the center of our sampler blocks and we'll be handling them plenty, we don't want to have to worry about bias edges.

To fix this problem, the four outer triangles need to be cut from two squares cut diagonally in half.

This flip-flops the bias and grain edges ...

... and makes for a square-in-square block with grain edges.  Hooray!

The Math ...

Ok - the math for Square-in-Square blocks is slightly more complicated than the Flying Geese blocks, but here's how it works.  The block is made from one center square, plus four triangles (from two squares, cut in half diagonally).

Measure one side of your center square.  Let's say that it's 3.5".  

  1. Divide this number by 1.4142.
  2. Add 3/8" (.375) for a seam allowance.  
  3. Round the final number up to the nearest 1/8".  
  4. Cut two squares using this measurement, and then cut each square in half, diagonally, to get your four outer triangles.

Let's walk through this using the actual numbers:

3.5 / 1.4142 = 2.4749

2.4749 + .375 = 2.8499

2.8499 rounded up to the nearest eighth - 2.875 or 2 7/8"

Cut 2 - 2 7/8" squares and then cut each in half diagonally.

Now, I'm not a huge fan of math ... but I am a huge fan of Excel ... so I built a little spreadsheet to do all the calculating and rounding for you.  You can access it here.  Just enter the measurement of the center square and it'll tell you what size to cut your smaller squares.  Easy Peasy!

So, fairly easy {spreadsheet} math and very easy block!  Believe it or not, this will be the end of our tutorials.  Practice this square and the Flying Geese blocks, and you'll be ready to start your first block next week.  Hooray!

1 comment:

  1. Wow. You make it look so easy. Thanks for all the details in this tutorial and the flying geese tutorial. I can't wait to get started!