How to fix holes in a boat?

[Nagual]

A small problem folks, we have a boat thats got a hole pics below. Question is can it be fixed? How why what etc? Really don't have a scoobie about boats at all, so if anyone knows a step by step simple as possible would be ace... If not, thanks anyway!

Hole is about 31 inches long and 13 wide at widest point.

 

[jojo]

Hi Nagual

That's a nice big crack you got there!

Firstly, what sort of boat is it and what is it made of? Where are the cracks on the boat? Looks like some sort of plastic, but knowing what type of boat it is would help in finding out what its made off and what to use to repair. I am a boat builder, mainly wood but even if I don't know for sure, i maybe able to find someone who does.

A few more pictures, of the whole boat, and where the cracks are, would help too.

 

[Nagual]

Cheers jojo, will try and get photos tomorrow. Its small blue plasticy dingy .. I think. Not mine so have no idea. Will get bivibabe to investigate tomorrow, and will post results and more information. Thanks for helping so far anyway.

 

[alpha_centaur]

I think it might be a tabur yak dinghy. Or similar. It's made of a sort of plastic type material but fiberglass sticks well to it.

I had one as a kid an spent many happy day's out in the bay fishing from it.

 

[jojo]

If it is a Tabur, it should be fairly easy to fix. I'd use epoxy and glass tape rather than polyester resin personally, it sticks much better.

 

[Nagual]

Here are a couple of pics of the boat, taken today. Its a TABUR yak II. As before any help and suggestions will be gratefully taken.

This shows some previous damage that was repaired, but now needs repaired again..

The back end of the boat, wooden bit for attaching a motor too, has begun to rot, but thats not so much a big deal.

 

[jojo]

Eeeeeeeee... this is poorly, isn't it

Well, I'd say the first thing is to bring the broken edges together as best you can. If you had access to both sides, which you don't have, the easiest way out is to use nylon cable ties.

If you can't use the ties, use pieces of ply, about 1/2' wide by 2" long, with a hole at each end, with these you can bridge the cracks and put a self tapping screw into each plastic edges and that should bring the edges reasonably back together.

When you've done that, you can sand the edges with coarse sand paper, (actually, you could do that first) and then degrease the surfaces with acetone. You can then sort of spot weld both edges together with epoxy between the little bit of wood holding the edges together. Try to get the epoxy to get between the edges to obtain the best possible repair. Then you can remove the wood or nylon ties and epoxy the gaps. Then you can epoxy some 2" tape over the joints.

You could use polyester resin and tape, but the adhesion is nowhere as good as epoxy. Then again, the boat is quite poorly and you may not want to spend too much on it.

Hope this helps.. If you need more info, just ask and I'll do my best to answer.

 

[jojo]

You can buy epoxy/tape/fillers online here

Polyester resin etc here

I have never used them but, they've been around a long while so should be fine.

From the pics, I think that would easily cost you around 50/60 quids for repairs that using epoxy.

Because the boat is in poor shape, I'd say it's not worth spending so much and go for the polyester.

Polyester resin is a lot cheaper. 2.5kg of resin and catalyst is about 10 quids, so you'd need that and some 2" tape, to cover the cracks, because the adhesion of polyester is not as good as epoxy, I'd also get some matt/cloth to cover the whole thing again. You'll also need acetone to degrease the whole repair surface before fibre glassing.

Anyway, have a look at the suppliers and decide what you want to do and we can take it from there!

 

[Nagual]

Many thanks jojo,

Those two sites were the main ones we, well I say we but in fairness bivibabe was the one who found them.. anyway 'we' looked at. As far as I can see East Coast Fiberglass looks to be very reasonable in price etc.

So far, as I see it anyways:

* 2.5KG Polyester Resin @ 10.24 here
* 4meter tape @ 1.50 here
* 1KG fillite @ 1.95 here
* 1Meter cloth @ 2.98 here

Giving us a total of 16.67 inv VAT


The amount of materials I think is right, at least for the big repair, and quite possibly the other small one too, however the costs are quite a bit less than what you estimated,so I think I've not accounted for something or underestimated the materials... ? To recap the repair process:

* Rough sand around repair area
* Clean with acetone
* Using ties or ply, draw sides together
* Spot weld edges together with resin
* Tape edges and cover with resin
* Cover with cloth and resin

Is that right? Where does the fillite come in to it, reading on the web suggests it is added to resin to make it stronger and more flexible, or is it used on its own? When they say it's added to resin by weight, do they mean resin + hardener, so if I had 100g of resin read to use to that I would have added or will add 100g of fillite ( if I was adding 100&#37..

Sorry for being so dense, but I'd rather ask silly questions now than make silly mistakes later..

 

[Sniper]

What's the name of the boat Mark "Titanic II" by any chance? :tapedshut

 

[Nagual]

What's the name of the boat Mark "Titanic II" by any chance? :tapedshut

Not got a name as of yet... shame a boat not having a name I know. So far came up with Arc, as it's a holy boat, or Bfer.

 

[British Red]

With that number of leaks I'd name it "Landrover Defender"

 

[jojo]

Yes, you got it in one, Nagual . The prices I had mentioned are for epoxy, which is much more expensive than polyester. I'd say use the polyester resin. I'd get the acetone from them at the same time as it's not easy to find otherwise.

The filite is a powder made of silicate microspheres that can be added to the polyester resin when you mixed it up, to make the mix lighter and easier to sand, but also to thicken it into a paste rather than liquid as the resin is on its own so you should use it when "spot welding" the gaps and filling to smooth the damage and sand it before you use the final cloth. Add it gradually until you get the right consistency, but don't take too long or your resin will start to harden up, when it starts to go off, don't use it as it won't stick that well!

And if you can, do it outside as the polyester stinks, and its probably preferable not to breathe the silica powder too much!

And did the pea green sieve in the poem The Owl and the Pussycat have a name?

 

[johnnytheboy]

To be honest with that amount of damage if you really wanted to fix it why dont you fiberglass the full bottom of the boat!!!!

You could fill the cavity with the expanding foam stuff meant for filling boat gaps to give it some strength behind the cracks, then fibreglass the full bottom of the boat.

The only other worthwhile solution i can think of is if possible split the bottom skin from the top skin of the boat then you can get in to repair both sides, we did it before and it was simply riveted together and was easily split.

Check the wood bit at the back doesnt run inside the boat, i had an old dingy that the transom allthough wooden and exposed at one section was also inside the boat as well and was all totally rotten when i got inside the two skins. If it does you could benefit from seperating the skins to replace this as well.

 

[smoggy]

I'm with Johnny on this, fill the cavity with foam and fibreglass the outside.....but use epoxy as polyester is pourus I believe!

Nigel.

 

[Nagual]

To be honest with that amount of damage if you really wanted to fix it why dont you fiberglass the full bottom of the boat!!!!

You could fill the cavity with the expanding foam stuff meant for filling boat gaps to give it some strength behind the cracks, then fibreglass the full bottom of the boat.

The only other worthwhile solution i can think of is if possible split the bottom skin from the top skin of the boat then you can get in to repair both sides, we did it before and it was simply riveted together and was easily split.

Check the wood bit at the back doesnt run inside the boat, i had an old dingy that the transom allthough wooden and exposed at one section was also inside the boat as well and was all totally rotten when i got inside the two skins. If it does you could benefit from seperating the skins to replace this as well.

Well, lets face it fiberglassing the entire bottom of the boat is a bit silly isn't it.. Not only is it highly expensive, it's not needed. The idea of splitting it has come up, but that I think requires even more knowledge, and tools which we just don't have. Never mind the getting it back together again.

I'm with Johnny on this, fill the cavity with foam and fibreglass the outside.....but use epoxy as polyester is pourus I believe!

Nigel.

Well to fill the entire cavity with foam would be so expensive, it may be easier to buy another boat.. So I'll assume you didn't mean the entire cavity. Polyester Resin isn't porous, at least as far as google says and jojo above - I don't think he's recommend using a rsin that would lead to us sinking in the middle of Loch Eck..

Thanks anyway for your replies guys, all is good to consider.


:You_Rock_

 

[jojo]

Polyester resin is porous, yes. That's caused by the evaporation of the solvents in the resin, that' s the bit that stinks! Epoxy hardens by chemical reaction between the two chemicals, there are no solvents to evaporate and create tiny holes.

But there are thousands of boats made of the stuff. The polyester is covered/protected by the gelcoat, which is a lot less porous than the polyester resin. You can achieve the same on a small boat with some paint. Its really not a problem in a small boat like this because most of the time its probably out of the water.

To get the water to penetrate the gelcoat and polyester, you need the weight of the boat in the water for long period which lead to osmosis ie:water molecules migrating into the polyester under pressure. The bigger and heavier the boat the more likely it is to get osmosis, but even then it's not at all certain to happen.

There is no chance your dinghy would get waterlogged that way.Far more likely to capsize it and fill up

 

[Tengu]

East Coast Fibreglass are a great company, Ive dealt with them before

 

[crazydave]

filler foam can be found pretty cheap or even see if a cavity wall company will donate the remains of a pack. I'd be inclined to fill it as it would guarantee bouyancy, then an epoxy tape overlay to plug the holes.

value wise you have the experience of making do and mending it which is priceless.

 

[johnnytheboy]

My friend had a dory like this but bigger, he cut the flat section of floor out and repaired the hull from inside, he then spaced it all out with wood and put the floor he cut out back in, he left holes and filled the rest with foam. I'm sure the expanding foam was cheap, its like two part epoxy but when it starts to react it turns into a foam and does some serious expanding.

When we split a boat skin it was simply a case of drilling the rivets out and the skins came apart, no great shakes, no special tools other than a drill.