Join Date: Nov 2008
Location: Penobscot Bay, Maine
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Re: Pad eyes for tethers and jacklines
Re the U-bolt resposes:
A marine u-bolt comes with 2 plates and 4 nuts/washers.
One pair goes under the substrate, one pair above it, and the bolts are tightened against each other. The 2 plates sandwich the substrate/deck/whatever. Properly bedded, they would be no less watertight than a conventional padeye.
They also resist sideways movement or bending because the 4 nuts and 2 plates, plus the backing plate, form a rigid unit. Perhaps incrementally less rigid than a forged 1-piece padeye, but I guess that's the crux of my question. How much less rigid is it, and how rigid does that union have to be (given that the bolt itself is strong enough) in order to reliably stop a fall overboard?
This is not something that will be subject to stress in normal use, remember. It sits there with a tether dangling from it, stressed no more than are the deck cleats many people tie off their jacklines to. So I don't see where repeated loading will gradually degrade the integrity of the boat surface that it's mounted on.
Again, I think it's a matter of whether the bolted joint can be made as safe as a one-piece joint. Because if it can, you can mount several of them for the cost of a Wichard.
(And perhaps thereby make yourself more apt to clip on to one!)