Air Castle Block - free pattern

Air Castle Block - free pattern

Air Castle block is an interesting design and another nine-patch. It is also a great design to add in corners of borders for quilts like Entwined Star by Anita Eaton.

This block is a great way of experimenting with different forms of triangle construction. I am using three different techniques to form the three different units. The corner units are half square triangles (HST), the middle unit is a square-in-a-square block where I use snowball corners and the star points have both quarter square triangles (QST) and HST. 

Air Castle quilt block
Air Castle quilt block

You will need three fabrics - dark, medium and light as well as a background fabric.  I used the orange as my light and the green and orange batik as my medium.

fabric squares cut
fabric squares cut

Here are the cutting instructions for three different sizes: 6", 9" and 12" finished.

 

6" finished

9" finished

12" finished

Background Fabric:

TWO 3" sqs
ONE 3 1/4" sq
FOUR 1 1/2" sq

TWO 4" sqs
ONE 4 1/4" sq
FOUR 2" sq

TWO 5" sqs
ONE 5 1/4" sq
FOUR 2 1/2" sq

Dark Fabric:

ONE 3 1/4" sq

ONE 4 1/4" sq

ONE 5 1/4" sq

Medium Fabric:

TWO 3" sqs

TWO 4" sqs

TWO 5" sqs

Light Fabric:

TWO 3" sqs
ONE 2 1/2" sq

TWO 4" sqs
ONE 3 1/2" sq

TWO 5" sqs
ONE 4 1/2" sq

 

Let's start with the corner units - HST squares.

You will need the TWO medium fabric squares and the TWO background squares of the same size. Draw a line through the diagonal, corner to corner on the wrong side of the background squares, then sew 1/4" on both sides of the line. Tip: It's ok to sew a slightly less than 1/4" seam here because you'll be trimming the unit to accurate size.

half square triangles
half square triangles

Now you can cut along the line and press open the triangles. Press the seam toward the background fabric (this helps with construction later). This will make a total of FOUR units. You will need to trim them to 2 1/2" [3 1/2" or 4 1/2" for the larger sizes] making sure the diagonal line on the ruler aligns with the seam.

FOUR HST units
FOUR HST units

The Center Unit

For this you will need the smallest light fabric square and the FOUR smallest background squares.

Start by drawing a diagonal line, corner to corner through the background squares, on the wrong side.

Place one of these background square in the corner of the light square so raw edges are even and diagonal line goes across the corner. Pieces should be right sides together.

Position background square in corner of light fabric square
Position bg square in corner of light fabric square

This time, stitch along the line. You can repeat for the opposite corner too.

First two corners sewn in place
First two corners sewn in place

Now you need to press those background squares in half so all points are meeting at the outer corner.

Press corners in place
Press corners in place

After they are pressed well, add the other two corners in the same way to complete the center unit.

Center unit completed - square in a square
Center unit completed

The Star Points

Let's try something a little different so we are dealing with less bias seams resulting in a more accurate block. You will need your largest background square and your dark square for step 1 and the remaining light squares for step 2.

Step 1: On the wrong side of your background square, draw two diagonal lines, from corner to corner in both directions. You are going to sew 1/4" from the right side of the line only, from the corner to the middle of the square, stopping when you get to the line. You can see this below.

quarter square triangles
quarter square triangles alternative method

Note: If you want the dark fabric on the opposite side, then sew on the left side of the line. Here again, it is ok to sew a slightly smaller seam. This gives you more room for trimming accurately.

Next cut along both lines and press the triangle units open. No need to trim here.

quarter square triangles step 1
quarter square triangles step 1

For the next step, cut your TWO light fabric squares in half through the diagonal.

FOUR of light triangles - two layers
FOUR of light triangles - two layers

You will sew these triangles to the triangles in the first step. Sew with the plain (light) triangles on top. This helps prevent stretching the seam as you sew.

Join the HST and QST together
Join the HST and QST together

Once joined, trim them using your ruler aligning the diagonal lines of the ruler to the seams of the block. You will need to trim them to 2 1/2" [3 1/2" or 4 1/2" for the larger sizes].

star points of air castle block
star points

Joining the Units

Now you have made all your units, so lay them out, rotating them as necessary to look like the photo below.

Units for air castle block layout
Units layout

First sew the units in rows. Tip: When stitching the center unit, sew with that unit on top so you can see where the seams intersect. That's where you want to sew through so your points are perfect.

make perfect points by stitching through intersecting seams
make perfect points by stitching through intersecting seams

Here are the rows.

rows made for air castle block
rows made

and finally join the rows to create your Air Castle block.

Finished air castle block
Air Castle Block finished

These are not my usual colors, but I really like this combination. It's bright and cheery don't you think?

© Copyright 2012- Arbee Designs. All Rights Reserved. This content is copyrighted by the respective teachers or authors of articles or lessons presented on this page. Unless otherwise indicated, all other content is the property of Arbee Designs. Customers and students may not make copies of the material for others without the permission of Arbee Designs.

Leave a comment

Please note, comments need to be approved before they are published.

Subscribe with RSS feeds

You can subscribe here with RSS feeds: click here to subscribe

Subscribe to our newsletter

Be the first to know about new collections and exclusive offers.