How to Make an Hourglass Block and Free Pattern

Swamp angel block | Hourglass Block

I love hourglass blocks they are super easy to make by joining two half square triangles together and they another good shortcut to learn for the beginner.

The maths to work out what size squares you need to cut is also super easy. Simply Add 1 1/4” to the finished block size ie Cut 5 1/4” square for 4” finished hourglass block or 3 1/4” for a 2” finished hourglass block.

However sometimes I like to add a bit more insurance as I prefer to trim my units before putting them into a block to ensure accuracy so for the above examples I would probably cut 5 1/2” square for 4” finished block and 3 1/2” square for 2” finished block.

Basic Hourglass Block

Hourglass block preparation

Prepare all your light squares by drawing a line as illustrated diagonally down the centre of the square.

Place a light 5 1/4” square together with a dark 5 1/4” square, rights sides together and stitch a SCANT 1/4” either side of the diagonal line.

Half square triangle sewing lines

Note: Scant means a few threads less than 1/4” seam allowance. If your final hour glass blocks are bigger they can be trimmed down before they are pieced into the larger blocks.

Using a ruler and rotary cutter cut on the diagonal line.

Press the seam allowance towards the darkest fabric.

Draw and line on the back across the centre of one of the half square triangle units as shown in picture below.

Prepare for hourglass block

Place the two half square triangles just made right sides together lining up dark fabric triangle against the light fabric triangle.

hour glass stitching guide

Stitch a SCANT 1/4” each side of the drawn line. Cut using a rotary cutter and ruler on the diagonal line.

Press two blocks open.

Use a square ruler to square up each of the hour glass blocks. The finished units should measure 4 1/2” square. Line up the 45° angle marked on the square and the 2 1/4” mark with the centre cross of each of the blocks trim along the right edge and across the top of the block. Turn the 180° and trim the last 2 sides until the block measures 4 1/2” square.

Swamp Angel Block into a quilt


Please find instructions for the above quilt Swamp Angel Quilt Pattern.

Amanda Bergamin

About Amanda Bergamin

Amanda has been quilting for 20 years and sewing most of her life having learnt from her mum and nana. She started Seabreeze Quilts about 5 years ago designing patterns for her etsy shop. Her favourite technique is needle turn applique, but she also uses machine applique, machine quilting (she quilts all her own quilts usually by machine) and machine piecing. No matter how long Amanda has been quilting she know the value of classes and learning from others. As well as teaching beginners classes, Amanda always makes sure to take at least one or two classes a year, as there hasn’t been a class she has attended where she has not learnt something new from the teacher or other students. Over the last two years she has run a free BOM on her blog Patterns for the month are available for free then up for sale in her etsy shop for a small price so you can catch up if you want to join in.

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