Papa Charlie Here: I do appreciate all the info about "tuning" a wing. I didn't read the right book. I had not put the wings together using trammel points, but I did do some very precise measuring, and the results are that I have wings that are square. I did go back and measure the tensions (15lbs /1/2" deflection) and they were very close. My question about tuning stems from years of bicycling..and years of truing wheels. As a practical matter, with no scientific basis that I could put my finger on, wheels that were built with uniform spoke tension did better that those that were not. I did notice that the difference in "tone" of tightened spoke varied a great deal with even the slightest tightening of a spoke..say less than an 1/8th of a turn. I worked at getting the same tune from all spokes of a wheel. Over the course of 40 something years of pretty serious biking, I broke very few spokes. Somewhere in my education, there was an explanation of the implications of tension in structure, compression, etc,.. I haven't started playing with it yet but I suspect that I'll find that it requires so little adjustment to change the "tune" of the drag wires, that it will not effect the squareness of the wing. Thanks again. Papa Charlie