Osmosis - Catastrophic ?

[ValleyForge]

Now I know a good bit about Osmosis, causes, cures (bills to prove !), preventative measures etc. from past craft but does anybody in the audience know of any actual catastrophic failures caused by this - ie final & complete hull integrity failure ? I ask because another of my elderly craft has succumbed - In my view its not important as the boat has limited value, is moored on inland waters & is for slow speed only. Will it, actually, ever break up, dissolve & sink ? ( PS - although 30 years old its actually quite comfy & smart up top, just not worth fixing). Any such experiences ?

 

[[2068]]

I would guess that over many years, if there was enough "juice" in the layup, and it were subjected to extreme freezing temperatures, then eventually the hull might just start to suffer, as in "not quite as strong as it was". I've never heard of this leading to any kind of catastrophic breakup or sinking though.

But if you keep it in the water, it'll probably keep floating for another few decades yet.

 

[ValleyForge]

Thanks DV, my thoughts too. I guess grp just isn't old enough yet for final decay to have arisen.

 

[fibz99]

I once load tested a grp lifeboat that had terminal 'Osmosis'. It was a 50man american liferaft about 25years old with loads of blisters about 60mm dia. The boat was designed to be picked up by one centeral hook, the load transferd to the hull thru 2 brass strips 3" wide and 8ft long, which were bolted thruhull to the lifting frame.
Test load was water bags, 3750kg was reached no problems, 4250kg was reached and the foward 6" of one brass strip sunk about 1/4" into the glass.
At 5000kg there was no more space in the boat for water bags, the lifeboat was left suspended for 1hr at 5000kg load.
After this the test load was removed, the brass stip had returned almost to its previous position, about 1/8" sunk in to the fiberglass along the front 4".
During later repairs it was found that this boat had serious delamination problems and large areas of dry fiber all thru the depth of the laminate.

Osmosis is definetly Catastrophic to you wallet when you try to repair it.

 

[oldgit]

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