Here’s a simple but effective tip for trimming up your half-square triangle blocks. Keep in mind, there’s more than one way to…(I love my cat too much to finish that phrase)…make a half-square, but here’s how I do it for the mystery quilt:

In this example, we are wanting 3 1/2″ finished blocks so I’m starting with 4″ squares. Draw a diagonal line, corner to corner, on the reverse side of the lightest fabric.Image of Two Fabric Squares

Put right sides together and use a 1/4″ foot ti stitch 1/4″ from either side. (If I was making a lot of these – like for last month’s block- I’d run them all through, stitching down one side (chain-piecing) and then turn them all and stitch down the other side of them all.)Image of Block with Stitching

Cut on the center line and press to the lighter fabric. The block should be larger than 3 1/2″ and have threads and tails (or ears) on them.

Here is The Tip: Using any ruler with a 45-degree line, place that line along the diagonal seam of your block and so that the over-all size after you trim the first two sides is still slightly larger than 3 1/2″. Notice the extra fabric outside of the 3 1/2″ marks? Trim the first two sides.Image of Block and Ruler

Spin your block and now line up the trimmed sides directly on the 3 1/2″ marks. Trim the last two sides.Image of Last Cut for Block

Maybe you figured this out on your own, but I needed a kind teacher to show me why I shouldn’t just trim that block to 3 1/2″ with the first cuts. I AM from the Show-Me State!

If you are making the River Heritage Block-of-the-Month Mystery Quilt, you are probably figuring out that there are a lot of half-square triangle blocks  in the design. Here is a pic of last month’s Trail of Tears block. Be ready to make some more half-square triangle blocks when the reveal for Month 6 comes out next week!

Having quilted for some time, I take for granted the piecing techniques I learned in classes. I hope sharing some of these techniques helps our newer quilters.

See my Mystery Quilt page for links to all of the months and Introduction or scroll down through the blog.  Mystery Quilt posts are published on the second Monday of each month at 9 a.m.  Each month has interesting river pictures, stories, or facts about river life along with the block of that month instructions. Month 6 is revealed June 11!

Focus fabric kits available in my Etsy shop: