Caroline,
This may help:
1/8 = 0.125
1/4 = 0.25
3/8 = 0.375
1/2 = 0.5
5/8 = 0.625
3/4 = 0.75
7/8 = 0.875

I will try your calculation. I am not familiar with your block and don't know what it is calculating but according to your instructions:
3.5 x 1.414 = 4.949
4.949 + 0.5 = 5.449
rounding to the nearest 1/8 gives you 5.5"

I hope I understood the instructions right.
Vasu

TY Vasu, Ill try that...

Caroline, Are you making a Square in a Square block from your Half-Square Triangles?

Here's another couple of ways to make them. I think the corner triangle (squares in the corner) method is easiest and doesn't give the seams in the center block like the HST's do. (jmo of course)

Hope this helps......

SharonG/FL-still in MI

Here is a link that might be useful: square in a square

Geezer, its just the opposite. The HSTs come from the square in a square. I think I just about have it figured out. I will never buy her books again. They are very hard to understand,then she has a video to help out. The book is really hard unless you get the video,,,sales gimic in my opinion..Grrr!!!

Caroline, I think there are easier ways to make a HST. Take the size of the finished block, add 1 inch, cut a square of each fabric that size, put them right sides together, draw a line from corner to corner, sew a scant 1/4 inch from each side of the line and cut on the line. Open up your fabric, press and square up. I even chain-sew when I do them.

I'm glad you posted about this problem as this let's the rest of us know about this book. You might want post the author and actual title of the book so we will know to watch out if there are other books by this author.

SharonG/FL-MI

Here is a link that might be useful: HST tutorial

I have made hundreds of hsts...Just was trying all the options with the Square in a Square ruler...not sure I want to name authors on here, but the S in a S title will give you a clue..