Yes you will cut blocks only need to be 4 1/2" x 4 1/2" for finished 12"
I think that would make the finished 9-patch to 12" not a DNP..
If the size of the finished DNP is to be 12" I believe it would need to start out with larger squares. According to
http://raevenfea.com/quilting/disappearing-nine-patch/ "Unfortunately, some common block sizes, like 6″, 8″, and 12″, end up requiring the starting squares be cut to third-inches,measurement." There was a thread that actually wanted a finished 12 - not 12.5 as title indicated and found what worked for ljptexas was to start with 4 3/4" and ended up unfinished 12.5"
Making a finished 12.5" disappearing 9 patch...
Janey - Neat people never make the exciting discoveries I do.
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