Making 1/2 Square Triangles Using 1 inch Formula

Making half square triangles using 1 inch formula

Learn why many quilters choose to add 1 inch to the triangle’s finished size and then “square up”. Cutting and sewing information included.  Handouts from the video can be downloaded by clicking on the links below.

Looking to buy Rotary Cutting Equipment? Follow these links:

Rotary Cutters

Rotary Mats

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download transcripts Formula rules for making 1 inch

download transcripts Video Transcript: CUTTING AND SEWING HALF SQUARE TRIANGLES – Making ½ Square Triangles Using 1 Inch Formula (#4 of 8 videos)

A half square triangle is formed when a square, cut on the straight of grain or cross grain, is split in half on the diagonal. Every half square triangle has one long side, and 2 shorter equal sides. They also have a 90 degree angle and two 45 degree angles.

In the following videos, I’ll go over some of the more popular methods for cutting and sewing this triangle and why you might choose one method over the other.

Here’s a quick look at some of these methods. You’ll learn how to make a template so you can mark your shape on fabric. It’s also a great tool for checking your sewing accuracy but I will say it is time consuming when you cut out fabric. A faster technique for cutting triangles is to use your rotary cutter to cut pairs of triangles. I’ll show you how to figure out the seam allowance when using this method and how to work on improving your accuracy.

If you have lots of triangles to make, you might want to view the “Half Square Triangle -Mass Production” video. This is a much faster process but you’ll need to learn how to “square up” in order to keep the triangles’ accuracy.

Some people prefer the security of paper piecing triangles. I’ll demonstrate how this works and you can decide if this method is for you.

If none of these demos ideas appeal to you, don’t worry. You can forgo the entire cutting and sewing process and purchase fabric printed with half square triangles.

You can find out more information about cutting and sewing half square triangles at under “Beginner Basics” then “Cutting” or “Sewing”.

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