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Sew Scrappy Sampler ~ Block 5

Quilt block # 5 of the Scrappy Sampler is all about half square triangles!

‘Tranquil Tree’

Half Square Triangle Tutorial
Lets do some Half Square Triangle (HST) Math (chart below)

~ This block is made up almost entirely of half square triangles.

I’m going to show you two methods to make half square triangles for any quilt project!  Both methods keep the bias on the diagonal of the block and NOT the edges of your block ~ which is important for keeping your HST blocks straight and your quilt from ‘warping’.


For this method add 7/8″ to the finished size you want your block to be and use that as the size of the two starting blocks.

Place two squares right sides together.  Draw one line from corner to corner.  Sew 1/4″ on each side of the drawn line.


Cut on the drawn line.

Half Square Triangle Tutorial

Open and press for two Half Square Triangles!

Half Square Triangle Tutorial


This second method will give you 8 half square triangles…

Start with two squares that are 1 3/4″ larger than the finished size times two.

For a 3″ finished HST ~ 3 x 2 = 6 +1.75 = 7.75 or 7 3/4″

Place two squares right sides together.  Draw a line from corner to corner on both diagonals.  Sew 1/4″ on each side of the two drawn lines.

Half Square Triangle Math

Cut on both drawn lines AND make a horizontal and vertical cut in center of block.

How to do half square triangle math tutorial

Open the triangles and carefully press… try not to drag your iron across the blocks so they don’t get distorted.

Half Square Triangle Math Tutorial

Here is some math for both options…

Finished HST block Unfinished HST block Starting block size

2 HST Method

Starting block size

8 HST Method

1″  1 1/2″  1 7/8″  3 3/4″
1 1/2″  2″  2 3/8″  4 3/4″
2″  2 1/2″  2 7/8″  5 3/4″
2 1/2″  3″  3 3/8″  6 3/4″
3″  3 1/2″  3 7/8″  7 3/4″
3 1/2″  4″  4 3/8″  8 3/4″
4″  4 1/2″  4 7/8″  9 3/4″
4 1/2″  5″  5 3/8″  10 3/4″
5″  5 1/2″  5 7/8″  11 3/4″



For my Tranquil Tree block I pressed the seams open so I wouldn’t have too much bulk at the seams…

Half Square Triangle Math

Even if your careful pressing it’s a good idea to square it… the extra step will help you avoid headaches later :)



5-scrappy-quilt-block-037Here are the links for the


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2 thoughts on “Sew Scrappy Sampler ~ Block 5”

    I am Linda Thompson from Southern Kentucky. I was wondering how you pick your fabric combinations. Do you design your own line? If not I just love the bold look without it being to modern. I do not like modern quilts but yours are very acceptable, actually not modern just bold and beautiful. Maybe a tutitorial on how to mix fabrics. I find I do not like to do that part very much because it is quite hard for me but I love piecing the quilts I make and one to another one when finished. Thank you in advance for any pointers on fabric selections and placement.

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