Pieced Squares - Introduction to Half-Square Triangles

McQ U - Intro to Half-Square TrianglesWatch our video...

Tricia Camp demonstrates an easy method for stitching half-square triangle units, starting with 2 fabric squares. Includes tips on figuring cutting size and trimming units.


Step-by-Step Instructions...

Step 1. Determine size to cut squares

The formula for cut size of a square to make a pieced square of half-square triangles is:  side of square + 7/8˝ (e.g. finished square = 2½˝, cut size of square is 3 3/8˝).

Step 2. Mark and Sew

Draw diagonal line on wrong side of lighter square. Referring to Diagram I, place marked square on darker square, right sides together. Sew ¼˝ seam on each side of marked line; cut apart on marked line. Open and press to make 2 pieced squares.

McQ U - Intro to Half-Square Triangles

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RE: I made a mistake
Ambec0308, if you want your half-square triangle units to finish at 6", you need to start with 6 7/8" squares for this method. Does that help?
I made a mistake
I cut my squares 6.5 inches and my finished HSTs are 6 inches. When I piece my quilt my pointsdo not line up. Can u trim down my HSTs to fit or do I have to start over. Any help is greatly appreciated.
Oversizing the Square
One method that has worked really well for me is to actually increase the size by 1 full inch, follow the marking, sewing and cutting directions, but then trim the final block to the required size. This gives you a little extra to trim off (extra step) but well worth it. also there are papers out there that help with hst - just google hst papers
Regarding video format
Thank you for your feedback - we are working on formatting our videos to be viewable on iOS devices. Meanwhile, our videos can be viewed on any other portable devices which have Flash Player installed, including Apple laptops.
Video format
I am unable to view your videos on my iPad. It would be nice to be able to view these in my craft room or while sitting on my couch. Ay thoughts on changing format so it can be viewed on phone or iPad? Thanks!
Response to soyasauce
Hello, I would recommend more practice, paying careful attention to both marking, and stitching straight on your marked line. I have found a very helpful product, Clearly Perfect Angles by New Leaf Stitches, that aids me in stitching a straight line from corner to corner. Their website is www.newleafstitches.com. Thanks for your comment!
line of the half-square triangle
i like your video but when i do mine, when it come to square it up my line is not always straight some time its crooked how come
Half-square triangles video
You are SO right! I was very nervous since this was my first video. I'll try to do a better job next time!
Half square triangles video
Tricia Camp refers to the half-square triangle units as "quarter-square" triangles.


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