Hooray for Half-Square Triangles

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So grateful to have Andrea from Knitty Bitties back for her sewing/quilting series.  Today she shares a tutorial for a type of quilting blocks.
Hello and happy week between Christmas and New Year’s Day. I kind of love this week … a chance to finally take a deep breath and relax. Play with your new ‘toys’ and watch your children play with theirs. Bake whatever it is you ran out of time to before Christmas. Catch a movie. Take a nap. Read a book.

And maybe, just maybe if you’re lucky … sew for FUN.

Today I’m going to tell you all about my favorite quilt piecing … the ‘half square triangle’ {HST from here on out}. The HST is such an easy piecing and is the basis for a lot of wonderful blocks/patterns.

Are you confused yet? Am I speaking Greek? Well don’t worry. Let me say again, I am NO expert and what I’m sharing with you is NOTHING new. But it might be new to you. And I started just like the rest of you, reading blogs, getting inspired and trying things. That’s it.

To create a half square triangle {HST}, you start with {2} squares of the same size. One square is typically a ‘neutral or solid’ while the other square is a print. Here I’ve shown you {4} squares because that is how many you need to start with to end up with {1} block.

My squares are each 3×3 and will create a finished block of approx. 5″ {after it is ‘squared’ up}.

After your squares are cut, lay them on top of each other right sides together {RST}. Then take a straight edge and a disappearing marking pen {or a pencil/chalk can work too} and mark from one point to the opposite point.

Pin the piece{s} together and take to your machine. When creating a project, it is easiest to cut all your squares, mark & pin them and then stitch them in batches so you’re not constantly stopping and switching your activity.

You are going to sew 1/4″ from EACH side of the line you marked. I start by sewing down one side of ALL my squares {this is called ‘chain piecing’} without snipping threads in between. Then when I get to the last set of squares, I turn it around and start down the other side of the line on all my squares.

Next, cut your chained squares apart. Then cut each square on the marked line. I like to use a straight edge and my rotary cutter.

Press seams. You can either press them open {shown on right} or press them to the side {shown on left}. Some patterns will indicate one or the other. I’ve found that more than anything it’s a preference thing … one is not better than the other, but often one is preferred over the other. Remember, do what works for you … because unless you’re entering your quilt into a quilting contest {in which case you are asking to be judged} I do not believe a quilting judge will track you down and give you a demerit.

Now onto the fun part … look what you can do with those {4} simple squares you created depending on how you arrange them::

My all time favorite, a pinwheel block::

Here’s an example of a table runner I made using HST::

A very popular choice right now, a ‘zig-zag’ block which can create a lovely chevron pattern::

Here is the quilt I made for my great niece this summer using using this pattern from Cluck, Cluck, Sew::

I have yet to try it, but love the look of  the ‘flying geese’ block::

Here is a lovely quilt I pinned as inspiration::

{Credit:: Red Pepper Quilts / Citrus Quilt}

And more ideas::

Pretty fun, right?

To complete your block, decide on a pattern {ideas above} and lay out your squares. For each block {4 squares sewn together} match up your top two squares {RST}, pin and sew 1/4″ from the right hand edge. Repeat for bottom two squares. Press seams. Match up the top and bottom sets, taking care to match up seams as best you can, pin & stitch along the long edge. Press seam. “Square up” your block using the center lines as your guide keeping your block square.

Here is another great tutorial for creating HST’s by sewing around the perimeter of your block. I’ve used this technique too and love it.

HST’s are a great scrap buster … so go rummage through your scraps {or go grab a few Fat Quarters from your quilt shop} and start sewing! Next time I’ll be back with a fun tutorial for your 5 or 6″ finished blocks.


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  2. says

    Great HST visual! Sooo many ways to use them I was getting confused on the layout for the chevron. Had to keep checking to see if I was laying them out right. ;)

  3. Kara says

    Thank you for posting this tutorial! I love the quilts you’ve made and the different ways you showed how to use the different half square blocks you made. I so appreciate you taking the time to do this!

  4. says

    Great little tutorial and inspiring to new quilters. Those half square triangles are such an important step in learning to put together a quilt! One thing, the other tutorial that you suggest is actually not for half square triangles, it is for quarter square triangles – the difference is that by sewing around the outside of the two squares and cutting cross diagonally your create squares that look the same, except the outside of each is on the bias — this type of peice is only used in specific blocks so don’t confuse it with the half square triangle which is much easier to put to gether with accuracy…

  5. says

    Ive been longing to make a quilt for ages now. I made my first one for my sisters baby shower back in October but it was simply squares sewed together in funky colors that detracted from any mistakes I might’ve made. THIS is actually a piece of art Andrea. Thanks for such a wonderful tutorial. I cant wait to try my hand at it:)

    • says

      HA! My first quilt(s) were nothing to brag about, LOL … but the beauty of quilting is you wash it, it gets all lovely and crinkly and you forget about the mistakes. I still have a hard time getting perfect seams, points, etc. But no one looks for those things when you hand them a hand made quilt. Your family won’t say no to snuggling up under a quilt you made because your lines aren’t straight. But you will SMILE every time you see your quilt used … promise :).

  6. says

    OK, It’s official!! I AM making a quilt this year. (other than my simple rag quilts which I don’t really consider a quilt) It may take me all year but I’ve been wanting to try my hand at quilt making for a while now. Your tutorial makes it seem so easy. You think the chevron quilt you posted is too complicated for a beginner? Thank you for the inspiration.


    • says

      Hi Jamie,
      First I think that YES you can make a quilt this year. Seriously … it is not that hard. Patience and practice ;). I do think that the chevron quilt could be possible for a beginner, but I might encourage you to try a few smaller projects (I love doing table runners) to get the basics of the blocks and quilting down on a small scale. After you feel comfortable with that, you’re really just doing it on a much larger scale ;).

      Happy Sewing!

  7. says

    Hello Mique,
    I am so excited to meet Andrea. I love sewing and her work is so inspirational and creative. I am now a new follower on Andrea’s blog, love it.
    Smiles, Paula

  8. Lauren Teather says

    Awesome tutorial Andrea!! Even myself … a NON–sewer …. feels like this is something I could do!! WOW – you have such a way of making things look so simple and beautiful! Thanks for the inspiration!