Calculate Square Size for 4 at a Time Half Square Triangles (HSTs)

Instructions to make HSTs 4 at a time can be found in the Shoo Fly traditional blocks video here: https://youtu.be/lDTOOQgkie4?si=e4uCSuIYuhOlJ4LM

Calculations below produce a slightly oversized unit you can trim down to exact size.

To calculate what size squares to use:

1. Divide the desired unit size by .64
2. Round up to the nearest 1/4″
3. Add 1/4″ so the finished unit can be trimmed to exact size

For a 1.5″ HSTs:
1.5″ / .64 = 2.34″
Round up = 2.5″
Add 1/4″ = 2.75″

For a 2.5″ HSTs:
2.5″ / .64 = 3.90″
Round up = 4″
Add 1/4″ = 4.25″

For a 3.5″ HSTs:
3.5″ / .64 = 5.46″
Round up = 5.5″
Add 1/4″ = 5.75″