Dent in my plywood hull! Help please

LittleSister

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. . .
If however it failed with as little encouragement as you suggested, then it may sadly be indicative of the condition of the rest of the ply....!

I must have knocked the anchor without realising it. I’d like to think the boat isn’t

yep. Any tips? . . .

My concern is why did just dropping an anchor make such a big hole. Either the anchor is very heavy or the ply very thin (or rotten!). . . .

You should not be able to punch a hole in the hull by knocking the anchor. Even dropping it from a height shouldn't do that.

I suspect your hull is rotten, at least in places.

You say you'd like to think that the boat isn't in poor condition, but that doesn't make it so. Remember your life might well depend on the integrity of the hull

I think all the good advice on here about how to repair the hole is a red herring until you have established whether and to what extent the hull is rotten. To do that you need the assistance of someone who is familiar with wooden (and preferably ply) boats, in my view.
 

Fr J Hackett

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You should not be able to punch a hole in the hull by knocking the anchor. Even dropping it from a height shouldn't do that.

I suspect your hull is rotten, at least in places.

You say you'd like to think that the boat isn't in poor condition, but that doesn't make it so. Remember your life might well depend on the integrity of the hull

I think all the good advice on here about how to repair the hole is a red herring until you have established whether and to what extent the hull is rotten. To do that you need the assistance of someone who is familiar with wooden (and preferably ply) boats, in my view.
We or at least me don't know the thickness of the ply it actually looks quite thin but does seem fresh rather than rotten.
 

S04

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Looking at the second picture, there seems to be an existing glass/resin (?) repair just to the left of the new damaged area.
 

jwilson

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I suspect the OP means a hole in the hull from the the anchor locker not the actual foredeck. I'd cut away damage then a substantial ply patch with epoxy on the inside, then fill and fair the outside of the hull with epoxy or polyester filler. I know I'm a bodger, but I do aim to do reasonably high quality and long lasting bodges.

Hacker's is the real perfect fix, but needs more skill, which I know he has.
 

LittleSister

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We or at least me don't know the thickness of the ply it actually looks quite thin but does seem fresh rather than rotten.

If it is thin, that means it is a small, light boat, and the anchor will be likewise of modest weight. Even a very heavy anchor (for that boat) should not be able to punch a hole in the hull simply by 'knocking it'.

The hull of any boat, however thin, should be quite capable of taking a heavy footfall, bumping into a pontoon or mooring buoy, hitting a floating railway sleeper or tree branch, etc.
 
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Wansworth

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You should not be able to punch a hole in the hull by knocking the anchor. Even dropping it from a height shouldn't do that.

I suspect your hull is rotten, at least in places.

You say you'd like to think that the boat isn't in poor condition, but that doesn't make it so. Remember your life might well depend on the integrity of the hull

I think all the good advice on here about how to repair the hole is a red herring until you have established whether and to what extent the hull is rotten. To do that you need the assistance of someone who is familiar with wooden (and preferably ply) boats, in my view.
Sound plywood even thin is quite resistant
 

38mess

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I remember some guys at our club breaking up a ply boat years ago, they couldn't put a sledgehammer through the hull, in the end they sawed it into pieces with a chainsaw then burnt it in a skip. I remember being impressed with the toughness of the plywood. So something not right with this.
 

Rappey

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I dont understand what part of the boat is in the pics. The anchor was placed on the deck but the hole is below the waterline ?
What am i missing ?
 

john_morris_uk

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All of these proposed fixes are easy, one of the great things about epoxy resin is that it fills the gaps with something stronger than the original so accuracy, whilst aesthetically pleasing,isn't vital. While you could just fill the dent with car body filler or somesuch the concern is that the piece has been , or was already, weakened. Hence the suggestions of either removing and replacing the area or reinforcing from below. "Fibreglass" being thin won't do much reinforcing even though it is quite strong.
The ordinary "fibreglass" uses a polyester resin which does stick to other things very well, you need an epoxy resin which is much better. So forget Halfords and use a chandlery or an composite specialist
“The ordinary "fibreglass" uses a polyester resin which does stick to other things very well..”

Surely you mean doesn’t.

To the OP. Please don’t use polyester resin fibreglass as available from car body shops etc. Epoxy resin is the best stuff as mentioned by numerous people in their replies.

Whereabouts is the boat?
 

DownWest

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Looking at the first two pics, I am having trouble with what has happened. Is the boat actually ply, or cold/hot moulded? and, it looks quite thin.. The raised lines around the damage look to be either a previous repair or maybe it is at a join?
Could the OP tell us the type of boat and maybe a photo from further away?

Spent my whole life around ply boats. That looks odd.
 

DoubleEnder

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I’m new to boats, and my anchor which I only just got, I stupidly put in the foredeck, which didn’t have any protection between it and the plywood hull.
Although I’m sure I was gentle putting it in, there is now a dent that is showing light from the other side. Essentially a small hole in the boat.
What should I do?
Any help + tips appreciated thanks!
Edit btw this is below the waterline!
View attachment 181181View attachment 181182View attachment 181180
Harvey you need to give some more information to get useful advice.
What sort of boat is it? How do use it? At sea?
What part of the boat has been damaged?
You say below the waterline- is it the hull itself that's damaged, or some part of the interior such as an anchor locker?

A hole in the hull below the waterline is potentially a very worrying thing and should be dealt with carefully and thoroughly. But also not necessarily too difficult.
The pictures make it quite difficult to know what’s going on
 
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