Shifted Spreader

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Tom Malkin

Hi Brion, I have a 1986 Hunter 40 Legend. I purchased the vessel 4 years ago in CT. where it had been on the hard for 5 years. Due to the rig configuration both spreaders have been pulled slightly aft forcing them out of their ideal position. As you can see from the photo, (and 2 up close angles), the lower left spreader has twisted downward. I have inspected them every year since purchase and the "at rest" position seems to remain the same but you can see there has been some movement when under strain. Should I be worried about this? Is it normal for this model of Hunter? Should I remedy the situation? Thanks, Tom
 
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Brion Toss

Stand from under

Hello, You know that this is a bad and dangerous thing. What you are probably hoping is that somehow someone can suspend the laws of physics for you, or that your inspections have some sort of talismanic effect on the spreaders. Sorry, you got trouble. The spreader bracket is, as you can see, angled aft. That angle was calculated to put the tip of the spreader in line with the load. This would result in more or less pure compression, with the spreader base bearing full-length on the inboard face of the bracket, and little load on that clevis pin. It appears that the mast is set up with way too little rake, or a weird bend, or both. So now just about all of the load is on that clevis pin, except for the bit that goes to the aft corner, and the spreader is trying to twist itself off the bracket. That downward shift means that the spreader is unstable in at least two dimensions. Scary. So. Check your manual for info on proper rake and bend. Addressing them should put your spreaders where they belong. If it does, pull the stick and replace those spreaders. Fair leads, Brion Toss
 
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Tom Malkin

I Under Stand

Hi Brion, Thanks for the warning. Guess I knew it was bad but wasen't sure how to fix it or what it would cost. I have been sailing for over 40 years and know every other system on a sail boat but when it comes to the rig I have no clew (LOL). Presently the boat has about 5inches of prebend but where do I get the correct info on the Rake & Prebend for an 86' Hunter 40 as I have no books on the boat? Where can I learn how to tune the rig without being dangerous. Thanks again for your help. Tom Malkin
 
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Tom Malkin

I Under Stand

Hi Brion, Your help is much appreciated. I understand your warning and will attempt to remedy the problem. I have been sailing for over 40 years and know every other system on a boat but when it comes to the rig I have no clew (LOL). What resources would you suggest I use to find the prebend and rake specification and learn how to make these changes? The boat came with no manuals so I am at a loss. The prebend is about 5 inches at persent the rake I have never measured. How do you figure out the rake when there is prebend? Thanks Again, Tom
 

Alan

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Jun 2, 2004
4,174
Hunter 35.5 LI, NY
Tom

In general, mast prebend is set at one mast diameter give or take 10%. Mast rake should be set at 1.5-2% of the mast height. Again this is a number with a variable, but using these settings as a start will get you damn close. Good luck
 
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