Repairing damaged bilge keels

[Seasick Ian]

The bottoms of my Hurley 22's encapsulated keels have a few large gouges and several smaller areas of damage. As far as I can tell the ballast is lead, and i've read that this is secured with steel bands. I can't see any evidence of penetration through to the ballast, which is a positive.

My plan for repairing is to
1. Strip away all paint around the bottoms to a height of about 5-10cm, using either paint stripper or just sanding.
2. Use a dremel to clean out the gouges and get all the damaged areas back to bare material.
3. Fill the gouges with thickened epoxy and fair.
4. Laminate over the whole keel foot and up the sides 5-10cm using epoxy and woven rovings, maybe adding some kevlar. This would be the reinforcement, I wouldn't mould a keel shoe or stick any metal strips to it.

Complications
There looks to be the remains of a GRP shoe that has been fitted previously. Should i glass around/over this or just remove completely? Might be a right pain to remove.

The boat is a bilge keel and obviously rests on the keels. I can do a certain amount of grinding and fairing around the sides/edge, but to access the actual bottom surface, I think I need the boat in the crane slings. The boatyard said I could do this, if I get the boat lifted first thing in the morning and then set to work, hoping the epoxy will cure before the boat goes into the water the next day. Is this feasible? Would there be any issues with the boat being in slings for 24 hours? The slings come together at one central point, so the straps will be 'pinching' the sides of the hull somewhat. Hurley's are supposed to be tanks, so maybe ok on that front. I've seen other posts where people have basically man-handled the boat, supporting one keel on chocks and the other side jacked up supports directly on the hull, freeing up one keel at a time. I've only seen this for smaller/lighter boats though, don't fancy my chances with the Hurley.

Thoughts?

 

[Rum Run]

The plan sounds fine.
I'd probably grind the old attempt at a grp shoe off totally.
If you have access to heavy timbers, scaffold pole lengths, acrow props, hydraulic bottle or trolley jacks, maybe wooden wedges and some seamanlike ingenuity then dispensing with the crane will help your pocket and the timescale for resin curing.
Regarding the resin, maybe as this is effectively a sacrificial shoe rather than a structural part, it could be done in polyester resin followed by flowcoat? This would be very much cheaper than epoxy and would cure much faster in normal uk weather. I know it does not adhere so well to cured polyester as epoxy but surely the new material wouldn't just fall off! The longer cure time of epoxy might allow the new layup to slump under gravity before it sets unless you can vacuum bag it on too.

 

[Tranona]

Just patching and repairing rather than making a new shoe, suggest you use epoxy and cloth rather than rovings. Much easier to get round the curves. Doing it in 24 hours will be a challenge. Better if you can to jack it up to get access tot he bottom of the keels and take your time to make sure it all cures properly.

 

[VicS]

The bottoms of my Hurley 22's encapsulated keels have a few large gouges and several smaller areas of damage. As far as I can tell the ballast is lead, and i've read that this is secured with steel bands. I can't see any evidence of penetration through to the ballast, which is a positive.

My plan for repairing is to
1. Strip away all paint around the bottoms to a height of about 5-10cm, using either paint stripper or just sanding.
2. Use a dremel to clean out the gouges and get all the damaged areas back to bare material.
3. Fill the gouges with thickened epoxy and fair.
4. Laminate over the whole keel foot and up the sides 5-10cm using epoxy and woven rovings, maybe adding some kevlar. This would be the reinforcement, I wouldn't mould a keel shoe or stick any metal strips to it.

Complications
There looks to be the remains of a GRP shoe that has been fitted previously. Should i glass around/over this or just remove completely? Might be a right pain to remove.

The boat is a bilge keel and obviously rests on the keels. I can do a certain amount of grinding and fairing around the sides/edge, but to access the actual bottom surface, I think I need the boat in the crane slings. The boatyard said I could do this, if I get the boat lifted first thing in the morning and then set to work, hoping the epoxy will cure before the boat goes into the water the next day. Is this feasible? Would there be any issues with the boat being in slings for 24 hours? The slings come together at one central point, so the straps will be 'pinching' the sides of the hull somewhat. Hurley's are supposed to be tanks, so maybe ok on that front. I've seen other posts where people have basically man-handled the boat, supporting one keel on chocks and the other side jacked up supports directly on the hull, freeing up one keel at a time. I've only seen this for smaller/lighter boats though, don't fancy my chances with the Hurley.

Thoughts?

My boat has fibreglass keel shoes. When I lost one I bought a new one and fitted it. (Actually had to buy a pair but I knew someone who wanted the other one)

In your position I would have the boat lifted and supported with the keels hanging free

I would make good the damage along the lines you suggest

I would make a pair if new shoes about 1½" deep, the full length of the keels with glass mat and ordinary polyester resin and fit them ( a couple of layers of glass mat wetted out with resin in each and lower the boat into them.

 

[Fantasie 19]

My boat has fibreglass keel shoes. When I lost one I bought a new one and fitted it. (Actually had to buy a pair but I knew someone who wanted the other one)

In your position I would have the boat lifted and supported with the keels hanging free

I would make good the damage along the lines you suggest

I would make a pair if new shoes about 1½" deep, the full length of the keels with glass mat and ordinary polyester resin and fit them ( a couple of layers of glass mat wetted out with resin in each and lower the boat into them.

In addition to all of the above - give Nick Vass a call as well - what he doesn't know about Hurley's isn't worth knowing... www.omega-yachtservices.co.uk/

 

[Seasick Ian]

Thanks for the replies.

I've already bought a pack of west systems epoxy 1.2 kg, which should at least take care of the gouges and maybe of a few layers of laminate. My aim really is just to mitigate against any drastic damage from occurring, i.e water ingress of the encapsulated keel, and to reinforce the area a bit. I'd like to have some proper protective shoes fitted, by I don't really have the time, money or skill to get the boat into a position that will allow me adequate time and space for making a female mould, then casting a male plug and finally proper keel shoes x2. Maybe some other year I can do that, but for now I reckon I'll just reinforce the bottom with epoxy. I don't think I'd be happy using polyester to fill the deeper gouges, especially seeing as it's below the waterline and on a bit that will take a pounding: one thing I forgot to mention is that I keep the boat on a drying trot mooring.

I'll have a think about using various jacks and cradles, but I'd need a fair amount of help from the boatyard, and I suspect that help wouldn't be very forthcoming without extra payment, and in that case I'd be just as well using the crane; it has to get craned back into the water after all so might as well just do it then. Perhaps I could persuade them to give me 36-48 hours in the slings before going back in the water.

I'm a diver, if there was a way of doing some of this work underwater, I'd consider that as well, but as far as I know there aren't any feasible options there.

I'm a member of the HOA so i'll post to the Yahoo group too and see what they say.

 

[JumbleDuck]

I've heard good things about greenheart oak for shoes on keels.

 

[VicS]

I've heard good things about greenheart oak for shoes on keels.

How would you fasten it on?

 

[Seasick Ian]

I might have access to some greenheart actually, but I don't think I'll consider that due to the issues of shaping it, and then fixing it.

It just occurred to me I could hang a tarp from the rubbing strake all the way around, essentially forming a tent and then put a small heater in it to bring the temp up to speed the cure. I could do this while the boat is in the crane slings.

I'm also considering using my 2-tonne bottle jack somehow. I could jack up one side enough to remove the plank from under one keel and replace with two chocks, allowing me to repair the section between chocks, and so on. I don't know how I would use the jack though, against the inner keel root? How would I spread the load?

 

[JumbleDuck]

How would you fasten it on?

I think the idea is that you bond it on with Sikaflex or the like ... though that raises some questions about what to do if/when it wears out. I'm interested (I had to have my boat's keel rebuilt when I bought her as she had spent 20 years on drying moorings) but a little dubious.

 

[nemodreams]

Bear in mind epoxy used cloth will take so long to set it slumps terrbily - runs out of the layup - even worse when working 'on the ceiling' as it were ! Why carbon fibre stuff is vacuum bagged.

Also - I think I am right in saying epoxy should not be used with normal loose mat - as it stuck together with something that does not bond well with epoxy ( woven cloth is ok ) Taht said - I have done it and it seemed ok ?

I would fill the holes with epoxy putty. Do not leave yourself to much to sand back - its hard and is a pig !
Once fair - I would coat it with several coats of thickened epoxy - no mat. That will not slump. All that could be done ok one end at a time.

A 2 ton normal halfrauds car trolley jack ( cheapo like mine ) will lift one keel at a time. I have done mine ( invader 22 - prob similar weight to yours ) - it feels it but does it ok.
However - you need some blocks under there to start with. Mine was always lifted on to about 9 inches of blocking just for some headroom to work.
So long as one side is well supported - the other side will jack on to one block - one end. Do half a keel at a go.
The old grp shoe ? Have a go at it - if its 'on there' leave - just fair it out.

Then as said - epoxy the whole bottoms - 250mm up or so. As may coats as you want.

 

[Seasick Ian]

Would the saturated cloth sag even if the epoxy mix were thickened with colliodal silica? I plan on following the 'wet method' outlined here:

http://www.westsystem.com/ss/applying-cloth-tape/

I could get the boat craned onto some big fat sleepers that would give me enough clearance to get the bottle jack + support pad directly under the keel, rather than bracing the jack on the hull somewhere...

 

[Kyle2]

I have been mulling over these issues, as I would like to reinforce the bottoms of the GRP keels on my Snapdragon next winter. I considered having stainless steel shoes made, but can't see how I would fix them on, as I wouldn't want to drill into the keels in case water got in. I think I can raise the keels one at a time with jacks, as suggested above, and am thinking of building up the bottoms of the keels with polyester resin and glass mat, then wrapping in woven glass or kevlar tape and epoxy, about 5cm up the keels, for abrasion resistance and strength. I have already used a similar technique on the rudder, although that was easier as I was able to remove the rudder and so do the job the right way up! It seems to be wearing well though!

 

[Jim@sea]

I would also drill the keels where you are going to apply the fibreglass matt and screw in some stainless steel screws leaving say 1/4" sticking out, that way the fibreglass will grip the underneath of the head of the screw and make it less likely to come away in the future.

 

[TQA]

Here is how I would tackle this.

I would start by making a mold for the base of the keel. Take some 2 inch thick board cut in half length wise and cut out a half keel from each. Add some parcel tape to the faces and screw down to another board already face with parcel tape. Close is good enough. Now lay up two keel cap pieces at least an inch thick depending on the existing damage. It might be worth while to include some kevlar for increased abrasion resistance.

I would do one side at a time. Drop the keels on to railway sleepers or similar Working on the inside of the keel using a heavy duty piece of angle iron with some wooden packing pieces to spread the load long enough to get the ends under bulkheads I would jack the keel up just high enough to remove the sleeper. 4 jack stands to support the hull.

Now grind away all the loose stuff on the base of the keel. Drill 3 or 4 holes through the caps. Using lag bolts with hex heads and repair washers do a trial fit of the cap on to the keel. When you are happy mix up some resin and silica filler to the consistency of thick peanut butter. Butter it on to the cap. Screw the cap on to the keel. When the filler starts to ooze out take some wide tape and tape up the joint. I use 3 in wide parcel tape for this sort of job. When it has set remove the bolts and fill the holes. Remove the tape and fair the joint. If you think the caps are going to have a hard life It might be worth reinforcing the joint with some 2 in wide g/f tape and resin. Finish the job off with g/f primer and a/f.

A jig saw or bandsaw would help with the mold. A small disk grinder with 35 grit would help with the grinding. A torture board would help with the fairing.

 

[Kyle2]

I am wondering, if I had stainless steel keel shoes made, could I attach them without having to drill the keels? I read that epoxy doesn't stick well to stainless steel, but maybe Sikaflex would stick them on OK?

 

[William_H]

Well if it were me with damaged bilge keels... I would not feel the need to go to stainless steel although if cleaned well epoxy will stick to ali or ss. I have repaired the bottom of my lead in GRP drop keel many times. I use epoxy. However I have always taken my time so able to leave over night before adding more layers or filler. I have also added kevlar when I had it. This should give a really tough skin but you would want a few layers because it can be in effect be torn off rather than fail itself when damaged.
Anyway I would be looking at raising the hull off the bilge keels or at least raising part of the bilge keels.
You may consider blocks or similar to raise your bottle jack up to the centre keel just aft of the bow so tip the whole boat back on the back of the bilge keels exposing the bottom of the front of the keels. Do the same lifting the stern.
Or as said you might lift one side so that a jack at the back of the raised bilge keel leaves all the rest accessible.
You will need lots of blocks and jacks and do be very careful backing up jacks before you get too far under. Lot of planning needed. But i do think doing it will suspended in a crane will make you want to rush the job. I think it will take time to fair harden, sand and fair again. olewill

 

[davey]

Fibreglass keels went out of fashion for this very reason! Some cradle building seems to be required.

I came to this thread as a Google result although it is not really what I wanted. I am trying to research bilge-plate-repair for a Colvic Springtide 25. The problem is that the marina's straddle-carrier that lifted the boat had a cack-handed operator who let the weight of the boat go onto one bilge plate. The result is a cracked hull and of course an unseaworthy boat that cannot now be sailed away to a far less expensive boat club. This fiasco occurred at Easter and it is now the end of August. The boat owners insurance is Third Party so the problem is (1) Getting the boat repaired. (2) Getting the Marina's insurance to pay for the repair. (3) Finding a competent person who can repair the boat so that it is at least as strong as it was before.

Before the accident I had a quick look at how the bilge plates were fastened and I was not impressed. If it was my boat I would be making templates of the shape of the inside of the hull and then having a trip to Afon Steel-benders in Swansea. Afon are able to bend steel up to two inches thick so having 10 mm reinforcing plates made to the shape of the hull should be easy for them. Unfortunately when the topic was broached with the owner he began yelling and screaming "I'm not a millionaire!" As the prospects of finding suitable material for repairing the boat in a skip are extremely slim, its another stalemate situation. The marina's insurance company won't pay until the repair is done and they are given the bill and that is another log-jam. Possibly the boat could be taken the four miles to the boat club by lorry? This would avoid paying the marina storage fees that are considerably in excess of £100 per month. I towed that boat from Dover to Wales so all these shenanigans are quite absurd. Unfortunately the truly excellent 4x4 that I had given a major overhaul to has been stolen so I cannot tow the boat to the club.

BOAT = Bring Out Another Thousand!

 

[William_H]

Sort of a new post but here goes. I can not see the inside of the hull where it is cracked but if it is fairly clear GRP hull as suggested by your idea of steel reinforcing. I would consider cleaning up the inside hull surface after removing the keel attach bolts and laying up additional epoxy GRP to provide thickness so strength. Taper the GRP layers out to the edges of a patch that probably will be size limited by other hull structure. Now if you use carbon fibre instead of glass you will get additional stiffness in the patch. Then drill through the bolt holes and fit very large washers to the bolts.
If it is not practical to reinforce the inside you may consider laying up CF on the outside under the bilge keel plates, suitably faired in to make it look like it was original.
Incidentally further to the above old discussion when working up side down with GRP you can often keep it in place with cling wrap. It being easy to see through and mould to what you want while being easily released when resin is hard.
good luck olewill