Make 8 units at a time with this easy half-square triangle tutorial. Use this formula to figure out the size of the beginning squares. No guesswork!
In a few weeks, I will release a new quilt pattern that features a pieced block (above) and a block with piecing and applique’. Today I will show you how I’ve been making lots of half-square triangles (HST) shown in my recent patterns and published quilts. When I have to create many units at a time, I have a few options.
Half-square triangle methods
1. The traditional method has you cutting squares of the two different fabrics measuring 7/8″ larger than the finished size of the unit you need. This is easy but… it can get tricky and leave room for error if the finished size is not a round number such as 3″.
2. You can use the Strip Tube Ruler as I show in this tutorial. Just sew two strips together, position the ruler, cut the triangles and press them open. You need to have that ruler, though.
3. There is another method that also uses strips (see this tutorial) where you marked the strip with vertical and diagonal lines, stitch around the diagonal lines, and cut the units. You do make many units at a time, but it does take a while to mark the strips.
4. You can use the half-square triangles in a roll of paper as I did for this quilt, and each roll comes marked for the specific size of the unit. Ideally, you stock the rolls of papers with the sizes you use the most, except you will not be able to use them for odd sizes.
5. Another paper product is the Cake Mix (I used it here). It works much the same way as the roll of paper.
7. The 8-at-a-time method has now become my favorite because I can make half-square triangles of any size by using a simple formula: Finished size x 2 plus 1-3/4″. That’s it! Let me show you.
Half-square triangle tutorial
Say I need to make 2-1/2″ (unfinished – before it is attached to other units to complete the block) half-square triangles to use in a block. The finished size of the half-square triangle will be 2″ (the extra 1/2″ makes up the seam allowances). Using the formula above: 2 x 2 + 1-3/4″ = 5-3/4″. Thus, I cut one square of each fabric at 5-3/4″.
How many squares of each fabric will I need? If I need 4 units per block and I will make 11 blocks: 4 x 11 = 44 divided by 8 (the number of units I get per pair of squares) equals 5.5 or 6 squares from each fabric. There will be leftover HST.
Next, I mark the wrong side of the lighter square with two diagonal lines.
I then pin the squares with right sides together, and stitch 1/4″ away from the marked lines. Notice where I placed the pins – the fabrics won’t slide and the pins will not get in the way of the presser foot.
I like to press the square pair before cutting it to set the seams. Then, first I cut crosswise, then diagonally twice. Done!
Here they are – trim the ‘ears’ and you are ready to use them on the block. They do come out perfectly every time and, when you need to make hundreds of them, I find this is the most fun way to go about it.
Look at how I work through this block. I prepare the building units from the outside in…
… stitch them together and finish the block. Isn’t this a cool block? I will soon have the pattern ready and I think you will like it. It will showcase an upcoming line by Northcott.
Speaking of Riley Blake Fabrics, look at my quilt Twinkling Stars at Quilts, Etc. in Sandy, Utah. They were selling the kits a while ago, and the fabrics have the same 30s look like the one I used on the block above. You can find this pattern in my Etsy store, PiecedBrain.
But I digress. Of the methods I mentioned above or that you’ve used, which one is your favorite way to make HST? I hope this half-square triangle tutorial is helpful to you. I like it because you do not need additional tools, you can use it for any size HST, and the math is not complicated.
Last week, I showed you my latest Christmas quilt, Family Traditions, published in the November issue of American Quilter magazine. The winner of the magazine copy and a few other goodies is:
Right now I am working on a flannel rag quilt for my niece to replace one that I had made for her several Christmases ago. It was ruined when her basement flooded. And also making masks – lots of masks. Thanks!
Congratulations, Delaine! I will email you soon to get your mailing information. In the meantime, a big Thank You to everyone who participated – it is awesome to hear from you as it makes me feel I am not alone in the blogosphere!
Have a safe week,