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[Colin Bishop]

This is actually about my 1:1 scale boat but might have modelling applications too so I'm posting it here. Hopefully somebody may be able to help.

Briefly, the boat is a lifting keel 21 footer. During the season I've had water seepage around the keel box which, after a lot of investigation, appears to be due to some water penetration around the bolts of the internal fittings supporting the keel and to a previous owner securing a gasket plate to the underside of the hull using screws which have penetrated the bottom of the hull - prat!

The boat is currently ashore on a cradle. I can treat the problem on the inside with sealant and re laminate along the base of the box but obviously it's best to tackle the problem from the outside to stop the water penetrating in the first place. The screw holes can be drilled out and filled with epoxy and shorter ones used so no real problem there. However, to get at the bolted on and fairly rusted but still functional guides at each end of the keel box the keel will have to be dropped which means hiring the yard crane, then the fittings may not want to come out (they are encapsulated on the inside). If they do they may be damaged in the process and you can see where this is heading moneywise! It's an old boat so I don't want to spend a fortune. (I haven't got one!).

What I am wondering is whether I can flood a low viscosity sealant around the fittings and adjacent areas which will work its way in by capilliary action and then set to fill any gaps. A bit like the stuff they use to harden rotted wood although this would not seem to be suitable for GRP. A bit of searching on the Web suggests that there are low viscosity epoxy resins available which might do the job and I'm wondering if any of you on the Forum with extensive GRP experience could suggest something suitable. Ideally I'd like to be able yo use a plant sprayer to squirt it in. All suggestions gratefully received.

Some pictures below, they look vaguely rude don't they?! 

Colin

[Shipmate60]

Colin,
It depends if you want a permanent solution or just one that works.
The best way is to drop the whole thing, strip it all down, clean, paint and refit as you first described, making repairs or modifications as you go.
There is however another way if you can remove the bolts one at a time and reseal individually with silicone sealant.
Or use Polyester resin Gel Coat Repair.
This flows easily and will flow into all the cracks and holes. But will make removing any parts sealed this way a real pig.

Bob

[Colin Bishop]

Thanks Bob, You've summarised my dilemma. Basically I want something which will work for a year or two pending a full strip down but which doesn't make things more difficult in the future. As you say, pouring gelcoat over the bolts will only make things harder and might not work anyway given the limited access. Drawing the bolts will only be possible if the keel comes right out and will entail hacking out the encapsulating GRP on the inside. I'm on a marina hardstanding and the yard facilities are limited. It's too easy to start running up open ended bills in this situation. That's why I'm after some something that will seek out and fill cracks in the presence of moisture. There seem to be some epoxy resins that might do this but I don't have direct experience of them - hence this query. The polyester resins I have used previously would be too viscious. We are talking hairline type cracks here.

Colin

[Welsh_Druid]

If they are only hairline cracks how about  "Captain Tolleys Creeping Crack Cure"  ?

http://www.captaintolley.co.uk/

Don B

[splodger]

If they are only hairline cracks how about  "Captain Tolleys Creeping Crack Cure"  ?

http://www.captaintolley.co.uk/

Don B

When I first read this, I was sure it must be something to hold up the trousers of men on building sites.

[anmo]

'Captain Trolley's creeping crack cure' would be even more useful for many building site workers of course. I was sure this must be some kind of joke, but I had a look at the website, and if it does what it claims to do, it looks like very useful stuff.  Seems surprising that it isn't more widely known.

[Welsh_Druid]

'Captain Trolley's creeping crack cure' would be even more useful for many building site workers of course. I was sure this must be some kind of joke, but I had a look at the website, and if it does what it claims to do, it looks like very useful stuff.  Seems surprising that it isn't more widely known.

Its probably the name - most peoples reaction when you say it to them is the same as the last three postings 

Mind you - a name like that isn't easily forgotten 

BUT - it really does work - it fixed leaks on the windows on my Westerly "Pentland" ketch and they didn't leak again despite some horrendous weather.

Could be very useful for those annoying hard to fix leaks in our model boats too.

Don B.

[Colin Bishop]

Actually I've got some of this stuff, known about it for years like most yotties. It is a possible option but the repair will be below the waterline which is not the usual place to use it. Still, it may be the way forward if I can't find anything better.

Anyway, at least you lot have learned something today!  

[Shipmate60]

And you do know the real solution.
Strip it all down, take your time, do the job once, but do it RIGHT.
But then we all know this. I know I can be a short cut harry at times!!!
I cant be perfect, just ask my wife.

Bob

[Colin Bishop]

It's economics too Bob. The water ingress is about a pint or less a day when she is afloat all the time, hardly any comes in while she's on the drying marina berth as she is only afloat 3 hours or so a day and there are no crew on board to increase the pressure. The boat is 23 years old and worth maybe five grand max. A complete stripout and repair could cost £1,500 easily. It's just cost me £130 to have her hauled out and pressure washed. No cheap facilities on the South Coast and I don't have space to store her at home. No, I know I shouldn't be doing it but everyone needs a focus!

Colin

[ambernblu]

Colin...

Now if you were in the Torbay area, I could probably put you onto someone who would give you a dry land winter storage for the boat - at a reasonable price! 

Cheers, Brian

[Colin Bishop]

Well, thanks for the thought Brian, it's only a couple of hundred miles away! 

Problem is that to drop the keel the boat has to be over 5 feet  above the ground so you either need to have a crane or be a gravedigger. The best time to take it to a boatyard would be in the summer when business is slack so it needs a bit of forward planning. Anyway, the bodge solution may see my ownership out. You tend to have a lot of workable compromises on a 20 year old boat. (Including the owner  )

[Shipmate60]

If you aint gonna remove it build a small box round it and pour polyester resin in it.
That will seal all the cracks and leaks, just dont expect it to come out without a hell of a struggle.

Bob

[MikeK]

If you aint gonna remove it build a small box round it and pour polyester resin in it.
That will seal all the cracks and leaks, just dont expect it to come out without a hell of a struggle.

Bob

Now that takes me back to the old days !! If in doubt, build a cement box round it 

MikeK

[Colin Bishop]

Wouldn't work Bob, look at the picture. If you did manage to build a box somehow it would almost certainly lock the keel mechanism. And I reckon the polyester wouldn't bond too well either. Looks like it will have to be the creeping crack cure....

[Subculture]

I wil tell you something. Epoxy resins are MUCH more expensive than polyester. They are stronger, but in this instance polyester resin will be strong enough. You can thin down polyester resin with styrene if you need to make it more runny.

Not sure how the moisture will afeect things, not aware of any epoxy products designed to seal out moisture, I'd have thought this would inhibit the cure if anything.

Andy

[Shipmate60]

Colin,
Are you going to seal the keel box from outside the hull?

Bob

[Colin Bishop]

The surveyor I consulted suggested just sealing the inside as it would be too difficult/expensive to deal with the outside. I'm a belt and braces guy though, so I'd like to have a shot at trying to cure the problem at the source. I think some of the water must have been getting in via the screwholes which are easily plugged. Any ingress around the keel support bolt holes is likely to be due to hairline cracks which may respond to the creeping crack cure treatment or  an epoxy equivalent. I don't think polyester will adequately bond in the circumstances. I have also got hold of some G4 sealant which is a one part polyurethane capable of curing down to 0 degrees C in the presence of moisture. It is commonly used to seal the bottoms of ponds and concrete but can be used on GRP as well. It will probably do the job on the inside prior to reinforcing with GRP laminate but it seems to be a gel formulation which will not penetrate in the same way as creeping crack cure. I think maybe a combination of these methods might do the job. Granted it isn't a "proper" job but economic consoderations preclude this at the moment. I just wish I'd stuck to models - much cheaper!

[John W E]

hi there, Colin

First Rule & only Rule

What the old man used to say 'There is no RAC or AA or anything similar' you can call out apart from the Lifeboat when you are out in the middle of the sea.  When you call them out, you are in great need - you are sinking!.  So, a bodge doesnt do.   YOUR LIFE AND THE CREW OF YOUR VESSEL DEPEND ON IT - do the job right - YOUR LIFE DEPENDS ON IT.

Looking at the photographs, I can see the guideroller and two bolts and the first question I must ask is, could you cut back through the keelbox to get to the other side of the bolts - the nut end?  or, do you know - is there a steel plate with tap threads in glassed in to the keel box?   Why I ask, is, if you are certain it is weeping through there, you must remove the guideroller and bolts and repair the surrounding area, because, its obviously the lateral movement of the keel, on the rollers that is causing the wear and seepage.

Any bodge job will only last so long.   & give out when least expected.

No doubt it will be when you least expect.

I know you are thinking of the cost at this time, but to do a good job and the right job will pay benefits in the long run and you will be able to sleep in your hammock with an easy mind.

Aye
John E
BLUEBIRD

[Shipmate60]

I cant argue with BLUEBIRD.

Bob

[Colin Bishop]

Good advice guys but no, I'm not absolutely certain that it is leaking around the bolts. It may be coming from the screwholes which have penetrated the hull, four of which are concealed under a bodge repair. There probably is some sort of backing plate, almost certainly with nuts on the other side as somebody has cut a slot on the bolt heads, presumably to enable the nuts to be tightened properly fom the inside. I need to think about this some more and I also need to understand more how the keel mechanism actually works, not all boats of this type (Jaguar 21 were constructed the same way). There is an owner's association website I belong to and I will be asking around in a bit more detail on that. I also hope to get some photos of the inside of the keel case next week which may help - there are access holes in the upper part of the case to the bushes which stop the keel going south if the strap breaks. John's point about lateral pressure exerted by the keel is very valid. I need to try and find out just how the keel is supported when the boat heels. Many thanks for the input - much appreciated.

Paul, that's a good suggestion. I don't have a tow car but the boat does have a trailer so something might be worked out.

[John W E]

Hi Colin

if we could have more photographs of the 'bodged' areas around the screws and more of the internal keel box - and possibly of the area where the guideroller is mounted from the inside, that would give us more to work on - in understanding the problem and also help us with possible cures.

Aye
John E
BLUEBIRD

[Colin Bishop]

Hi John,

The "bodge" completely hides the internal mounting of the keel guide supports. see pic below. The blue stuff is the bodge repair and the bulge almost certainly covers the inner mountings of the aft keel support fitting. The forward one is similarly encapsulated. I think I should say that there is no sign of structural weakness and a thrash around the Solent in a F5 during the Summer did not increase water ingress in any way which is still quite minimal. As far as the screws securing the gasket plate are concerned, they are pretty obvious and can be treated with epoxy putty and the holes re drilled using shorter screws.

One of the owner association members has posted a description of overhauling his keel which I can email you if you are interested (PM me your Email). I have Emailed him to ask for further details and possibly some pictures of how he did it. Hopefully I can get down next week to try and take some pics of the interior of the keel case. I agree with you 100% that a proper job is the way to go but I need to keep the cost down to realiistic levels and fully understanding the problem and thinking the solution through is essential to this. The way things are going I envisage a temporary repair followed by a trip to the local boatyard next Summer. Very much appreciate your interest and advice.

Colin

[Shipmate60]

Colin,
I just cant visualise the whole thing.
Where are you, I am in Locks Heath.
I could always pop down and have a chat over a cup of coffee if you are buying!!!

Bob

[Colin Bishop]

Bob, The boat is at Thornham Marina, Emsworth - not too far away. Happy to buy you a coffee or a pint if you are interested. Cheers,  Colin