Ah, a sad day for the 22! And we were having so much fun, in some of the first real summery weather we've had here in the NW. Downwind under spin with 240 lbs of crew weight on the wire, hull flying in flat water, when BANG! The spin hlyd lets loose, causing momentary confusion. We hoist again, and I happen to look up to see the mast falling off severely to port, with the stbd upper inner diamond hanging limply. We douse the chute and limp home to assess the damage. Upon dropping the mast, we expected to find a tang that had let go, or a turnbuckle failure. But no, all of the diamonds were intact, with no evidence of damage. The turnbuckles came apart easily, the threads on the studs were fine. The female threads in the open body, chrome plated bronze turnbuckles are a bit hard to see clearly, but they seem fine too, with no hint of stripping anywhere. The pics show the mast with the diamonds relaxed, but it looked pretty similar before we loosened them. So we'd love to come to some understanding as to what happened. Did the hlyd release somehow stress the mast? Did something giving way induce the release? Are they unrelated? Did the mast just bend under spin load(modest as it was)? Which doesn't seem too likely as the bend is just above the upper tang of the inner diamond, not above the hounds. We're baffled at this point. And we'd like to know what went wrong to avoid such an expensive(I assume) event in the future.
Here's the fine print. This boat is the prototype ARC 22, with the original 38.5' aluminum mast. It's currently running a single spreader, double diamond set up, but was initially rigged with 3 spreaders. So there are a fair amount of filled holes. And it's 20 years old, and spent much of it's life near salt water, some corrosion. Although the bend is no where near any of these defects. All the diamond wires and turnbuckles were replaced at the beginning of last season, and again show no failures. The mast strikes me as pretty highly stressed, with the outer diamonds tensioned to induce 3.5" of prebend, and the inners tensioned considerably less, just enough to stabilze the tube between the outer diamond attachment points. All was carefully set up 6 weeks ago to Aquarius' precise specifications.
So, thoughts gentlemen?
And, it appears we're in the market for a new extrusion. Any sources other than Aquarius? Anyone know who supplies them with tubes? Or other spar mfgrs who could supply a suitable stick? The profile is 6" x 3.25", I can get the wall thickness later in the week. Any used 22 masts out there?
Thanks guys, sure wanna get her back running soon, it's prime season here in MT.
