Trimming makes accurate Half Square Triangle units

With all of our lucky fabrics picked out and cut, the next task is to make the Half Square Triangle (HST) units for the Lucky Monkey Tail Mug Rug. For this project the pieces are cut larger than required so that we can trim our units to the correct size. I find this method the quickest way – without any special tools – to make accurate units. When working with small pieces it’s even more important than regular quilting to have accurate units to sew together. Let’s get started!

Make Half Square Triangle units

Sew together 6 sets of squares to make HSTs


4 sets of background fabric and gold 2½ squares, which when sewn together, will make a total of 8 background/gold HSTs

2 sets of background fabric and green 2½” squares, which will make a total of 4 background/green HSTs

Mark diagonal line on back of background fabric square

Draw on the wrong side of the six background fabric 2½” squares one diagonal line.

Match up four background squares right side facing with four gold 2½” squares.

Match up the remaining two background squares right side facing with two green 2½” squares.
Sew ¼ʺ away from each side of the line on all six squares.

Making two HST units at once by cutting on drawn line

I chain piece these units by sewing down one side of each square one after the other without cutting the threads in between.

Then I turn the string of squares and sew down the opposite side on all of the squares before removing from the machine.

Cut on the drawn line. Press the seam to the darker fabric.

Time for some accurate trimming

Trim units to 2″ square

Trim each unit to 2″ square.

My best tips here are to take your time, in good lighting, and hold the ruler firmly in place when cutting. Notice how the 45 degree angle line on the ruler lines runs exactly between the two halves – this will ensure your half square triangles are the same size. Turn the unit and trim the other two sides as well.

This method creates accurate half square triangles by trimming units to size after creating them. These are the only units we need to make – now to layout the design and put it all together!

Related posts

Stitch regulation on the PFAFF powerquilter 1600

Don’t miss it! Courtepointe Québec celebrates its quilting artisans!

Finishing a quilt block to size: Here’s what it takes


Debra Neiman January 29, 2016 - 6:49 pm
Wonderfully. I love using bloc loc too.
Sarah Vanderburgh January 29, 2016 - 7:04 pm
Thanks for commenting, Debra. I have heard good things about the bloc loc at my local quilt shop. Hope you enjoy some quilting time this weekend!
Add Comment