How to Square Up Hourglass & Pinwheel Blocks: No special ruler required!

This post is a supplementary tutorial for the Quick Block Calculator.

When using the shortcut methods to make Hourglass and Pinwheel blocks, you often have to "square up" the block to the correct size you need. If these blocks are not squared up properly, you will end up with very wonky looking squares that will only be good for the scrap pile.

In this post, I'll show you a simple method for squaring up Hourglass, Pinwheel, and Half Square Triangle blocks that doesn't require a special ruler.

MATERIALS

• Square quilt ruler at least 8" x 8".
• Rotary cutter
• Masking tape or transparent quilt ruler tape.

INSTRUCTIONS

Hour Glass

1. Divide the desired block size in half, e.g. 4½"÷ 2 = 2¼"
2. Find this number on the ruler.
3. Place a piece of tape horizontally and vertically on the ruler to mark the center of the block.
4. Line up intersecting point of the tape with the center of the block.
5. Line up the 45º angle with angle of the block.

6.  With a rotary cutter, cut off the exposed ends of the block.

7.  Turn the ruler and block 180º and, once again, line up the halfway point with the center of the block.

8.  With a rotary cutter, cut off the exposed ends of the block.

Pinwheel

Half Square Triangle