Originally Posted by sparkys_mom
Well, that's the first explanation I've ever seen that actually made sense - at least to me. I've been fighting with a block that is supposed to be 8 1/2" but it keeps coming out to just over 8 1/4" to just under 8 1/2". I'd probably just finesse it if it were for me but I'm sending it to someone so I want it really exact. Here's the block at Quilter's Cache and this makes total, total sense.
http://www.quilterscache.com/N/NorthernLightsBlock.html
THANK YOU!!!!!
I love that site but I don't like her method for making HST's. I always do the square, mark the diagonal and sew a scant 1/4" on both sides of the line. When I try to use her method, the fabric gets distorted or I get confused or both. It also helps if you make the squares a smidgeon bigger than you need and trim them back down after pressing open. The "rule" for HST's is 7/8" more than the finished size so I just do a full inch. That extra 1/8" isn't going to waste too much fabric and will really pay off in the accuracy of the blocks.