Beginner Quilting Series: How to Make Half Square Triangles

Welcome to the beginner quilting series that I am hosting to prepare you for the On-Point QAL!
Today in the beginner quilting series, we are talking about making two a time half square triangles!


Welcome to the beginner quilting series that I am hosting to prepare you for the On-Point QAL!
Today in the beginner quilting series, we are talking about choosing fabric!


First, you can find the other posts in this series here-

   Available Cuts of Fabric

   Precuts

   Choosing Fabrics for a Quilt

   Supplies Needed to Make a Quilt

   Pressing, Cutting, and the 1/4" Seam


This is the last post in the 'Beginner Quilting Series' before the On Point QAL starts on Friday, March 1st!


You can read more about the On Point QAL-

     Solid Option Fabric Requirements and Schedule (plus lots of colored version for ideas)

     Print/Scrappy Option Fabric Requirements


So, let's get into Half Square Triangles...

Half square triangles are one of the most popular blocks in quilting.  They are wonderful because you can do so many things with them!  The are beautiful on their own but they can be arranged in so many ways to make so may designs.  Because of this, they really are a great block to be comfortable making.

There are quite a few ways you can make these- one at a time, two at a time, four at a time, eight at a time...lol so many ways!  But don't let that confuse you, all of those ways can be easy as long as you understand the concept of what you are doing.

For today's tutorial, we are specifically talking about making 2 at a time Half Square Triangles.  This is the method we will be using in the On-Point Quilt Along so that is why we are focused on this specific way.

I have found that there are basically two schools of thought on making Half Squares Triangles (which is usually abbreviated HST).  The first is make them bigger than you need and trim them down to be perfect.  The second is to make them the no trim way, which means they should turn out exactly the size you need without trimming (except you do need to cut of the little dog ears in these, so you are trimming but just not taking from the block size when you trim).

I personally favor the make them bigger, then trim them down method.  It leaves room for some error.  If your HST don't turn out perfect right from the sewing machine, its ok because you will trim them to the perfect size anyway!  That is what I'll be showing today.  

If you would like to learn the No-trim way, you can google that (how to make no trim half square triangles) and find a tutorial that will walk you through it.

Start with two squares.  Here I'm using a print square and a background square.  Also here, I am starting with 3" squares (and it'll be making 2- 2.5" HST) but this works for any size HST.

Generally, the rule I do is this- I add 1/2" to the unfinished HST size.  So if I want, 2.5" unfinished HST then I start with 2- 3" squares.  If I want 4.5" unfinished HST, then I start with 2- 5" squares.  If after to do this whole method, your HST are still wonky and not turning out the right size after trimming, try starting with a bigger square...maybe go up another 1/2" in size and see if that helps.

Use your ruler and position it like I have below.  You want to divide the square into two equal triangles.  So you line your ruler up from one corner to the opposite corner.

Then draw a line down the middle.

NOTE: To draw the lines on blocks like this, you typically draw the lines on the darker square so that the lines don't show through to the good side on the light fabric.  I drew them on the white square so you could see them better.

Also, I draw my lines with a Frixion pen.  The pen has ink that disappears with heat.  So, when you press the HST, the ink goes away.  Frixion pens were not made for fabric.  As such some people have found that when the fabric gets cold, the lines come back.  You can use any type of fabric making item that you are comfortable with.  Also, specifically here, since we are drawing on the back of the fabric, I'm fine using a Frixion pen.  Try different quilt marking items here and pick what works for you.


Next, sew 1/4" on one side of the line.  Turn the block around and sew 1/4" on the other side of the line.

FOR BEGINNERS OR FOR STRAIGHTER SEWING----
When you are first starting out, it may be helpful for you to draw 3 lines (instead of just the one down the middle).  One down the middle, one 1/4" to the left of the middle, and one 1/4" to the right of the middle.  Like this-

Then you will sew along the two outer lines.  You end up with this.

Then, you cut on the center line.  This will give you two pieces like this.

Open them up and press. (I usually press the seam allowance to the darker fabric unless the pattern you are using states otherwise)

You will have two HST now.  These are bigger than the size that you are looking for and also probably not perfect in shape.

To make them perfect, we will trim them to the size we need in the pattern.  

Line the 45 degree line of the ruler on the diagonal with the fabric line between the two fabrics (see my 45 degree line- its yellow and black- going across the diagonal of the block).

Be mindful of where your bottom corner is.  You need to make sure you still leave room to trim the other side.

Look at the below picture...remember how we are trimming these HST to 2.5" square.  When trimming the first side, you need to leave a little extra past the vertical 2.5" line and past the horizontal 2.5" line.

Trim away the excess.  This side is now perfectly straight.

Rotate the block 180 degrees.  Line the 45 degree line on the ruler along the diagonal again.  This time, the bottom and left sides should be exactly on the measurement that you want the square to be- 2.5" in this case.

Trim away the excess.

Repeat these steps for the 2nd HST.

You are left with two perfect HSTs in exactly the size you wanted them to be.

One more thing, if you are still having trouble getting you HST to be perfect.  Don't hesitate to start with bigger squares.  If you start with bigger squares, you'll have more room for error because you'll have more fabric there for trimming.  There is no shame in doing this.  Chances are after you make a bunch, you'll be able to size down a little on your beginning squares because you'll develop better skills with practice.

That wraps it up for today :) If you have any questions, let me know!



Talk soon,

Jessica