6 February 2015

Making Half Square Triangles - An Updated Tutorial

It seems like I have been spending an awful lot of time making HST's lately.  Last week I shared my progress on my third WoW-E! quilt and that I have plans for making a fourth version using an on point setting.  I must be nuts.

WoW-E! in SOLIDS on point - 57" x 71"

It was a year and a half ago that I first shared my Half Square Triangle (HST) tutorial here on the blog.  Lots of things have changed since then... including how I make my HST's.  So I thought these little time saving tips were worthy of adding to the blog and updating my HST tutorial.

Making Half Square Triangles - A Tutorial

For the purpose of this diagram the right side of the fabric is shown in pink, while the wrong side is shown in white.  Please note that the fabric squares should be ‘sandwiched’ with right sides facing together, and line up on all sides as accurately as possible.  The diagram does not show this accuracy for demonstrative purposes only.

First determine your finished size square.  For the purpose of this tutorial, I am using squares with a finished size of 2".  Add 1" to the finished size square to determine how big to cut your pieces.  So, I need to work with 3" squares to make my HST's.
Using your rotary cutter and acrylic ruler, cut your fabric along the width of the fabric to make strips measuring 3" and sub-cut these strips into 3" squares.

Previously, I had been using this method, which is the most accurate.....   Take two squares and ‘sandwich’ them with right sides facing together as shown in Figure A.  Use a pencil and ruler to draw a diagonal line on the wrong side of the fabric, from the top corner to the bottom corner as shown in blue in Figure B.  Sew a ¼” seam on the right of the blue line from edge to edge as shown in red in Figure C.

Chain piece your HST's by continuing these steps shown in Figures A, B and C for about 10 other pairs of squares, sewing the seams, and without cutting the thread.  At the end of the last seam, turn your chain of sandwiches around and sew back along the opposite side of the guide line, 1/4" from that center line, on each sandwich square as shown in Figure D. 

But during the making of my latest batch of hst's, I used a piece of masking tape to mark a center line that is 1/4" offset from center.  Then I don't have to mark all those squares.  The corner of your block is lined up with the masking tape and your stitch line is 1/4" off of center.

When I turned my squares around to stitch the second seam, my foot also helped to guide me on the way back.

Here is a chain of squares I had sewn up for my WoW-E! {redo} quilt.

Remove the chain of squares from the machine and bring them to your cutting board.

Use your acrylic ruler to cut the squares along the diagonal between the seam lines.

Take the chain of pieces to the ironing board.  Clip the threads to separate the pieces.

Press the seams open.

Take the pressed units back to the cutting board.  Use your acrylic ruler to trim the first corner by lining up the diagonal dots along the seam line.  Make sure to allow for trimming of the other corner of the HST.  Notice the 2.5" marks along the ruler edge are not at the edge of the left and bottom of the HST unit?

Turn your unit around and trim the other corner.  Make sure the seam is aligned with the diagonal dots on your acrylic ruler and that the sides of your unit line up with the 2.5" marks.

Voila!  Perfect 2.5” Half Square Triangle Blocks!

These 2.5" HST's will finish at 2" when used in the patchwork blocks.

This updated post has been added to the Tutorial page.

How about you?  We all use those pesky versatile hst's in so many projects.
Do you have any tips to share?

Keep On Quilting On!


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Unknown said...

Thank you Lorna for this great Tutorial!
Hugs, Deborah

France Nadeau ❅ inspiration imagination creation said...

Hi Lorna! Very interesting post. I make my HSTs like you showed first, by marking a line diagonally on the wrong side of one square. But I will try with the piece of tape. I wonder if the sewing is as straight, though...

Ruth said...

Love that masking tape tip, marking takes a bit of time and this will be a great time saver!

Debra said...

Nice! This is a good idea. Also Omnigrid makes an eight inch square ruler that has a diagonal line on it that really helps to make sure your seam is centered as you trim your hst. Thanks!

Yvonne from Quilting Jetgirl said...

I use the masking tape trick all the time - it is a time saver for sure!

Daytona Damsel said...

Thanks for the tape idea. I have put off making HST's because of all the marking, now I can give it a try.

Quilt Fabric Pizazz said...

I am an old girl quilter and know a lot about quilting. I must say however, I love to follow your blog because it is so well written and illustrated. I learn new ideas and different ways to do things all the time. Love your quilts. Who says and old dog can't learn some new tricks? Thank you.

Soma @ inkTorrents.com said...

Thanks for the great tutorial!! Great idea with the masking tape. I can't wait to see the quilt done.


Anja @ Anja Quilts said...

What a great idea. I will definitely try that to save some time.

Doris Rice, The Quilting Queen said...

Fabuluous Tut and great pictures. I have used the tape and it works well. Have also used a static cling made specifically for half square triangles. I think it's called Clearly Perfect Angles.

Sarah Goer Quilts said...

Love this. Getting the tape out for my next HSTs. :-)

Carole @ From My Carolina Home said...

This method is the same as the one I use, with that one detail that is an AHA moment, that strip of tape! Brilliant! Mind if I link back to this tutorial on my blog?

allthingzsewn said...

So easy, even I caught it first go around. Thanks. Haven't talked to you for a little bit, Still waiting for the shop (God's timing) but everything here is fine, Good report from heart doctor and I'm actually exercising now.
Everything is good on this end. How is your end doing. Tired of snow?

P.S. Brought computer from work home (better) and in transferring files I seem to have lost a few things. Your e-mail being one. Sorry about personal comment on your public page.

Cheryl said...

This is the way I make HST's too, I agree with the trimming, I find that it really makes a difference in the points in the final quilt.

Patch the Giraffe said...

I also agree with the trimming although it's my least favorite part! Really like that quilt on point too, it's such a great design :)

Glinda ♥ said...

Brilliant tutorial ... next time I make a quilt with 144 HSTs, I'm definitely using your tape method :)

Sew Stitching Cute said...

Oh this is an awesome tutorial! Thank you for this! You're like me, always wanting to have the most proficient way of doing things! haha. Sometimes it stunts me on how long it takes to do things because I sometimes take more time trying to figure out how to do it more proficiently than actually doing it... I LOVE this! Can't wait to use this!

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