Originally Posted by Steve Huff
Irvin, I forget, but what machine are you using?
My observations on head compression: 1st, the most notable racket regarding this subject was the Prince Classic Oversize (the aluminum with the green throat). You rarely saw a restrung Prince Classic that had been restrung that wasn't "rounded" out. Prince had to know this because they weren't round coming out of the factory, and they were obviously strung. Stretching them was the most common cure for these rackets by most of the stringers I knew. Over the years, as rackets turned to graphite, Head Radicals seemed to be the most common rackets that tended to "round" out. I don't think it was flaw. Head designed these frames to be flexible, and flexible frames tended to do this. It's pretty well known that there is a lot of tension loss due to friction in the cross strings. As Irvin pointed out with his measurements, the cross strings normally restored the shape of the 2 rackets he strung. Radicals had 18 mains, 19 crosses, whereas the rackets Irvin strung had only 16 mains (pretty sure) and 19 crosses. The extra 2 mains of the Radical could have contributed to it's tendency to round out. I don't think this tendency is in any way a slam on Head. If you've read many of my posts, I think the Radical OS is one of the most versatile rackets made, and appeals to more levels of players, from beginner to advanced, than any other racket. But what makes them play well also contributes to the fact that they round out. Stringing the crosses at a higher tension than the mains is one way to help solve this. To me, it makes it a perfect candidate for a hybrid, with poly in the mains, synthetic (or multi) in the crosses, with the crosses at a higher tension. I rarely see this rounding out on other OS rackets. Why? They're so stiff. In essence, they're brittle.
I string enough rackets that I can compare. I string close to a thousand rackets/year, and have been stringing since 1979 (not always 1000/yr in the beginning, but still, over 10,000 rackets). I've strung on cheap 2-point machines (Court & Slope). I've also owned and used an Ektelon H, Serrano 550B (both 2 point "tanks"), a Winn 4pt machine, and now an Alpha Apex 6point machine with a Wise head. Frames deformed more with the cheap 2 pointers than the others. With the 6pt machines, deformation was least. Not because they held the rackets sturdier than the the Ektelon or Serrano, but because the 6 and 12 mounts were adjusted by a screw and not by hand, so it was easier to pull the frame out more (stretch it a tiny bit). Believe me, there were other ways to stretch frames, even on the cheap 2 pointer with Prince Classic frames. In the early 80's, frame braces were made for a reason--mainly to stretch aluminum oversize rackets. They weren't advertised that way, but that's what they were used for. Anyway, take my comments for what they are--my opinion.