Does GRP deteriorate when submerged in mud ?

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aneng

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There's a small abandoned GRP speedboat that's 60% submerged in mud, bow up, near me. It's been there for years. I was wondering would it be worth my while digging it out or whether it would be pointless due to GRP deterioration ? Does GRP deteriorate when submerged like that for years ?

Many thanks !
 
Does GRP deteriorate when submerged like that for years ?

ERR No.

Well not a lot. It's moisture level will be higher than if on land.

Otherwise all these GR boats that stay in the water year round in places like the Med and Florida would be in trouble.

Any plywood on the other hand will be in a sorry state.
 
Suggest a 'trial' dig alongside the hull, testing for 'softness' as you go, and look for 'sagging' of the hull sides, as they become uncovered :)

Also suggest that the Hull just might have become 'deformed' due to earth / mud around it exerting pressure upon it :(

anyways, if you have both time and energy go ahead! the sun is shining and summer is here, nothing to loose! :)
 
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Depends on the GRP.
It may have lost some its strength due to the resin 'hydrolysing' i.e. breaking down in water.
It may have fatigued due to years of wave action.
GRP has a fatigue mechanism due to either individual fibres breaking or fibres breaking adhesion of the resin forming micro-cracks.
It may have stressed itself being full of mud and water at low tide.
It could be holed due to settling on stones or the previous layer of decaying marine hardware....

Old speedboats with no engines are not expensive on ebay.
OTOH, you might be doing a valuable clean up of the shore...
OTOH, maybe it is home to some marine life now....?
 
Oh now you've given me far too many options ! I'm wondering if it's worth the effort - and risk - of eventually putting my safety in the hands of a hull that may crack or disintegrate when I'm in it ! Actually... strolling along the shoreline, I've found a couple of tenders that have obviously been abandoned (i.e. they have been submerged several times and are covered in mud, that are still attached to moorings.

Oh I don't know... I just want something small to tootle up and down the estuary in - maybe I should forget all about requisitioning one of the "abandoneds" and look to buy something that hasn't been upside-down in the mud for a decade. Trouble is, with almost no budget, that's going to be difficult !

What is a decent site to look for small boats on ? - or is it just ebay ?
 
Wow Quicky ! I just read your thread.... that's amazing !! I'm going to be following your progress eagerly ! I wish there was something like that near me... all I have is a half-sunk speedboat, a couple of absolutely minging tenders upside-down in the mud... and this......

2013-07-27175512_zpse882f84d.jpg


I did start another thread last year about that one - http://www.ybw.com/forums/showthread.php?329641-Abandoned-boat , but to be honest, it's not what I really want - even if it is abandoned (it's been there deteriorating for at least ten years).

I want what YOU'VE got !!! :D
 
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Being an 'old' fiberglass hull it will probably have timber stringers in the hull, I can almost guarantee they will be rotted due to water ingress, but fear not they are easy to fix and this will give you a chance to straighten her out if she is a bit of and odd shape.

I would be tempted to dig some of the mud out from the inside first, that way you can see what condition the bottom is like on the inside without having half the estuary sliding into a hole on the outside.

Good luck and fair winds. :)
 
aneng said:
Wow Quicky ! I just read your thread.... that's amazing !! I'm going to be following your progress eagerly ! I wish there was something like that near me... all I have is a half-sunk speedboat, a couple of absolutely minging tenders upside-down in the mud... and this......

2013-07-27175512_zpse882f84d.jpg


I did start another thread last year about that one - http://www.ybw.com/forums/showthread.php?329641-Abandoned-boat , but to be honest, it's not what I really want - even if it is abandoned (it's been there deteriorating for at least ten years).

I want what YOU'VE got !!! :D
Click to expand...

I like the boat in the picture, where do you live? I am always looking out for a pile of poo to do up ;)
 
How come it is sunk? You could dig it out to find it is holed. If you want something cheapish to potter about in how about a small inflatable dingy?
 
Go and look! It's the only way you'll ever know whether it is worth the effort. If you've got no budget then this is ideal for you.Dig it out, get it home, clean it down and then get a book on GRP repair. You'll love every minute of the project.
 
Here are a couple of better pics of the boat in question...


IMG_5751Small_zpsd3100179.jpg


IMG_5753Small_zps05c367b7.jpg


I've waded out to it and it's in very soft mud... I couldn't stand near it for more than a few seconds as I was sinking in it up to the top of my wellies.

There's no way I would be able to dig that out, purely because standing in that stuff is nigh on impossible, never mind standing in it and digging it !

However... I have another plan... and I was wondering if I could pick your esteemed brains to see if it's remotely sensible...

I'm planning on seeing if I can pull it out - very VERY slowly - by the bow eye, using some 8mm polyprop rope and a cable puller.
The rope has a breaking strain of about 1000Kg and the cable puller can manage double that. My theory says that if I apply a couple of hundred pounds of tension on the bow eye over several hours or days if need be, then it ought to slowly pull it out of the mud. If I can exert a tension greater than the weight of the boat plus whatever mud is inside, it *should* start to slide out - slowly. I'm hoping the bow eye doesn't shear off, but I think they are fairly strong points aren't they ? They need to be strong enough to take the weight of a boat plus assorted paraphernalia and a decent sized outboard up onto a trailer, and I'm guessing that the mud inside might be roughly equivalent of a large motor, so if I take it really slowly, I might get some movement on it.

What do you guys think ?
 
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aneng said:
Here are a couple of better pics of the boat in question...


IMG_5751Small_zpsd3100179.jpg


IMG_5753Small_zps05c367b7.jpg


I've waded out to it and it's in very soft mud... I couldn't stand near it for more than a few seconds as I was sinking in it up to the top of my wellies.

There's no way I would be able to dig that out, purely because standing in that stuff is nigh on impossible, never mind standing in it and digging it !

However... I have another plan... and I was wondering if I could pick your esteemed brains to see if it's remotely sensible...

I'm planning on seeing if I can pull it out - very VERY slowly - by the bow eye, using some 8mm polyprop rope and a cable puller.
The rope has a breaking strain of about 1000Kg and the cable puller can manage double that. My theory says that if I apply a couple of hundred pounds of tension on the bow eye over several hours or days if need be, then it ought to slowly pull it out of the mud. If I can exert a tension greater than the weight of the boat plus whatever mud is inside, it *should* start to slide out - slowly. I'm hoping the bow eye doesn't shear off, but I think they are fairly strong points aren't they ? They need to be strong enough to take the weight of a boat plus assorted paraphernalia and a decent sized outboard up onto a trailer, and I'm guessing that the mud inside might be roughly equivalent of a large motor, so if I take it really slowly, I might get some movement on it.

What do you guys think ?
Click to expand...


Looks like it fell out of the sky.....UFO's?:p
 
hartcjhart said:
looking at the pic, unless it is full of gold or drugs I would not bother
Click to expand...

Looks like a stunning hull, and may be well worth saving. You'd be doing everyone a massive favour by removing her anyway. I'd be asking the local port authority or Harbour Master's office if they wouldn't mind contributing some money towards the effort.

Is she in deep water at high tide? You could dig down and see if there's any way to pump air in. Then dig around her further, mark her with a bouy and see if you can wiggle her out with a mate's boat at high tide.

You could ask this lot http://www.mcsuk.org/ (and similar) if they can muster volunteers for a dig-out - if you can find some small boats to work from in the mud.

Keep us posted, and good luck!
 
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