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So (Sew) Many Half-Square Triangles

One Method for Making 8-at-a-time HST Blocks

A good friend of mine saw my current favorite quilt at the Piedmont Art Walk in May, and wanted to buy it. Of course he wanted to buy that one. It was the only quilt on display that was Not For Sale. Of course!

I told him he couldn't have that quilt, but that I would think about making something else for him in those same fabrics. But because I'm using some "found" fabrics, I can't make a copy of the same quilt -- I just don't have all the same fabrics anymore.

I've been trying to think of what I should make with the fabrics that I DO have. As with the other quilts I've made with my stash of plaids and stripes, I'm looking for a design that is simple and straightforward; the interest will come from the fabrics themselves. While I don't have a final design yet (I'll see what develops on the design floor), I'm starting with a basic building block of half-square triangles (HST). (As an aside, I think that's a strange name for a square block. Shouldn't it really be a half-square triangle square? Why do we leave off the final "square" in the name?)

I've chosen to do 4-inch finished HST blocks with a lighter half and a darker half (you can see the dark halves in one of the pictures above and the light halves in the other). Since I want the quilt to end up about 64" x 64", I'll need to make 256 HSTs. That's a lot! As I was looking around on the internet, I found a couple of tutorials for making HSTs eight at-a-time. The simple method has worked for me, so far, so I thought I'd share it with you.

Here's the basic idea:


Start with two squares of fabric, right sides together. On the back of the darker fabric, use your favorite marking tool to mark a line along both diagonals, from corner to corner. The orange lines in the diagram are the marking lines. (I used a Chaco chalk marker.)


Pin the two pieces of fabric together to prevent shifting. Sew two seams on each diagonal, 1/4 inch from each side of a marked line. The sew lines are the yellow dashed lines in the diagram.


Once all four seams are sewn, make four cuts: one on each of the marked diagonal lines, one vertical (midpoint of the top edge to midpoint of the bottom edge), and one horizontal (midpoint of one side to midpoint of the other side). All your cuts will run through the center of the block. The cut lines are marked in green on the diagram.


Separate the units and press them open. I pressed the seam allowance toward the darker fabric because it's quicker than pressing the seams open. But... I may change my mind when I start to put the quilt together. Ta da! Eight HSTs at once!

The 8 at-a-time method isn't so different from the two-at-a-time method you may have used before: mark one diagonal, sew 1/4 inch from each side of that diagonal, then cut on the marked line. Since I'm using fabric from shirts as well as yardage, I can't always cut large pieces. When that happens, I cut 5 1/4 inch squares, then use the two-at-a-time method. I've stacked a "two" on top of an "eight" so you can see how they compare.

Both methods ensure that the outside edges of the finished block are on the straight grain of the fabric, which helps with block stability.


Once the squares are pressed, trim them to size. I started with two 10 1/2 inch squares of fabric. When I pressed the eight HST blocks open, each was just under 5 inches square. I trimmed each one to 4 1/2 inches square, using the ruler's diagonal line on top of the seam line to keep the block straight. I trimmed one corner (two sides) then flipped the block 180 degrees and trimmed the other corner. Sometimes (like in the third photo) I was glad to be trimming, as my edges weren't always straight!

Trimming this many blocks takes a while! To pass the time while I'm doing this kind of mindless work, I enjoy listening to audiobooks I borrow from the library (I just finished -and recommend- The Unlikely Pilgrimage of Harold Fry and Miss Benson's Beetle, both by Rachel Joyce).

These fabrics do make a pretty pile of scraps:

I'll keep you posted on my progress. Enjoy your summer!


1 opmerking

11 aug. 2022

Love this!



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