Originally Posted by
Evie
I understand the rule of thumb if using two squares to make HSTs by sewing 1/4" on either side of a diagonal mark is to cut the squares 7/8" larger than the finished size of the HST block, or, like me, cut it a whole inch larger and then trim the HSTs to size. Can someone please explain how, when sewing two 5" charm squares by this method, I get 4-1/2" HSTs instead of the expected 4". I am truly puzzled! 
As you said, you start with 7/8" larger than the FINISHED size of the HST. You ended up with 4 1/2" HST which will be 4" when they are FINISHED. So it worked!!
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