I'm now a quarter of the way through the large onion ring magic square. Here's what it looks like:
This pattern is completed in one pass, and for those interested in following along, I've made a rough guide. I have numbered each onion ring and placed arrows between them to show the order of operations. The numbers are a bit hard to see, but I'm hoping that opening the image in a new tab will make them readable:
The triangular section above represents one pattern repeat. Complete four repeats to form a large magic square. The two small rings immediately after onion ring #43 are the beginning of the second repeat. Here is another photo, without numbers, for comparison:
In size 40 thread, the completed square should measure 13 inches by 13 inches. It will be several more months before I can finish the square, and I will keep my blog updated as I make progress.