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PostPosted: Tue Jul 30, 2013 2:48 pm 
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I had an eyestrap failure on my 2008 Wave last week. We were about 1,000 feet offshore in the Gulf of Mexico when we heard two pops followed by our mast falling on the leeward side of the boat. I assume the first pop was the left, bow eyestrap failing and the second pop was the flexural failure of the bow spreader pole. We were sailing with the jib, so it appeared that the load from the left forestay was transferred into the jib. Very exciting...

I have never heard of or seen anything like this happening. Are these failures at all common?


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PostPosted: Tue Jul 30, 2013 4:02 pm 
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Doesn't sound common, but long term mast up storage?

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PostPosted: Tue Jul 30, 2013 4:29 pm 
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We usually sail about one week each year. Otherwise, the mast is stored in our garage.

The day before the failure, we were sailing in moderate winds and flipped during a jibe. When the mast float hit the water it broke off, leaving only about a quarter inch of white plastic beyond the attachment clips/plates. The boat did not turtle and we were in fairly deep water, so I do not think the mast or any part of the boat hit the bottom. We easily righted the boat and continued sailing. Everything seemed fine for the remainder of the day and the first half of the next day.


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PostPosted: Tue Jul 30, 2013 4:37 pm 
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My only other guess would be an inverted wire connection loading the strap in an odd way. Very strange. These things take years and years and years of rental and resort abuse with very little real issue.

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PostPosted: Fri Aug 02, 2013 6:19 pm 
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I make a point of checking the screw/bolt to make sure they have not come loose. Mine have never come out thanks to them being forward where you see them, not something you notice until they start raddle when whey are leeward, but are you saying that the stay broke, I wouldn't guess that would be the first thing to part under that much tension, but guess it could.


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PostPosted: Sat Aug 03, 2013 10:04 am 
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We inspected all of the four bow screws (two on each side) after the failure and it appeared that all screws were at least snug tight. My conjecture at this point is that the failure was initiated by fatigue in the rear most of the two screws that attach the eye strap and the bow tang to the bow. The head of the failed screw simply broke off, leaving the left forestay supported by an eye strap connected only at the forward most fastener. The eye strap was overloaded in this condition and immediately failed.

Severe distortion can be seen in the eye strap that has been subject to normal use. I am not aware of any extreme events or overloads acting on this "good" eye strap, but the strap has clearly been plastically deformed so that its current geometry is much different than that of a new strap. When time permits, I plan to post some photographs of the remaining portion of the failed screw and strap. I also plan to post some pictures comparing the new/replacement eye straps with the surviving strap from the right bow.


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PostPosted: Sat Aug 03, 2013 5:22 pm 
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Understand that the Wave bow eye is formed to the angle of the load. It is not a standard eye. It bends toward the center of the boat a bit.

Sounds like the screw was the initial failure? Screws "could" fail from repeated tightening.

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PostPosted: Sat Aug 03, 2013 10:25 pm 
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Matt,

I have a couple of pictures that I would like you to see comparing my used strap and the new one. I think you will find the difference very interesting. Can you send me your email address privately?

Thanks,

Steve


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PostPosted: Sun Aug 04, 2013 10:00 am 
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Matt,

One other thing...

I have never used a Wave without a jib, so I browsed through some of the pictures on the Hobie site. I compared the orientation of the lower forestay cables on a Wave with the jib assembly and one without. The cable angle (between a horizontal line and the cable) on a Wave with the jib assembly is much flatter (smaller) than the angle on a Wave without the jib assembly. Does the jib assembly kit include an eye strap that is different than the standard eye strap? If so, I believe I have found the source of my problem. If not, this may be something worth looking into, since it does not appear that a single eye strap would accommodate both setups given the large change in cable angle.

By the way, it does appear that the eye straps that I have would align fairly well on a Wave with no jib assembly. I suspect I would not have had an eye strap failure using the standard, no jib setup.

I really appreciate your interest in this issue. Please let me know what you think.

Thanks,

Steve


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PostPosted: Sun Aug 04, 2013 9:15 pm 
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Quote:
it does not appear that a single eye strap would accommodate both setups given the large change in cable angle.


We use the same bridles and forestay with a jib kit... so no change in bridle angle. Is it a Hobie jib kit?

We only add a spreader bar which adds an abchor point for the Jib. It does not change the bridle angle.

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Matt Miller
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PostPosted: Sun Aug 04, 2013 9:17 pm 
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Quote:
Can you send me your email address privately?


You can PM or email me using the buttons at the bottom of each of my posts.

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PostPosted: Tue Aug 06, 2013 12:35 pm 
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Just an update for anyone interested...

The bow eye strap failure on my boat was caused by mast rigging modifications by the previous owner. The length of each bridle cable was reduced from the stock 60 inches to a modified 35 inches. This severely changed the geometry of the bridle cables and the force acting on them. Using basic engineering mechanics, I determined that the force in the modified bridle cables and the supporting hardware was increased by 436% over a stock setup. I am surprised the modified setup lasted as long as it did.

I want to thank Matt Miller and Key Sailing for working through this issue with me. My family and I plan to be sailing Hobie's for many years to come!


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PostPosted: Tue Aug 06, 2013 4:51 pm 
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I really can’t see the advantage of shorting those stays. You can probably thank the bow spreader also to help and hurt, or else you may have more damage in areas unknown, in other ways you would have had a super tight tramp at times, and your wake would have looked a bit different a rooster tail on the outboard sides when you are going straight. I have replaced my bow spreader a couple times and caulk them up to lessons learned and no way can you find a replacement (thinking something stronger) without a machine shop and staying stock is more important to me anyway (worth the money). :?

By the way I sail out of surfside, TX and the Texas City Dyke are you around that area?


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PostPosted: Wed Aug 07, 2013 8:02 am 
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surfslammer,

As far as I can tell, there is no advantage to shortening the bridle cables. Regarding the bow spreader, we have had no problems with that component until the eye strap failure. When our mast started to fall, a lot of load was transferred into the leading edge of the jib and the bow spreader. Our bow spreader failed in flexure due to this large concentrated load acting at its midpoint.

We sail out of central Alabama. We usually get about a weeks worth of sailing during our beach vacation, but it looks like we will get in a couple of extra days this year.

Take care...


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