Do we really need to coat / protect cast iron keels ?

Iron will rust much slower than steel. There is no danger of the iron keel melting away in the next 200 years. However it is necessary to support the anti fouling so spend a couple of hours each season with the wire brush ku rust and hammerite then prime and anti foul.
Newbies will see the surface rust stains as a problem so be prepared to slap an extra coat on at the right time if selling.
As Vyv said the oxidised iron (rust) is heavier than the iron it is formed from; It is worth noting that also it occupies more volume so can tighten up hull to iron keel joints.
 
H
rob2 said:
Used to live with this "problem" on a T24. Nice iron, bulbed keel which had been encapsulated with resin (may have pre-dated epoxy). Eventually the encapsulation cracekd, so we chiselled and ground off the remainder. Several coats off red lead and then antifouling. Each year there was a little less work to touch it up as the half tide mooring scoured the lot off! Still, the keel never suffered much fouling.

Do you still have the T24 first boat I ever sailed and went everywhere, I always like to see one on the water but sadly not often.

Rob.
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I had a Trapper 500 for twenty years with a cast iron Fin Keel, and every year it developed a few patches of rust and a few bits of antifoul fell off. I followed the advise of the Technicians at Blakes in Gosport and just patched it each year, It was no worse when I sold it than when I bought it and I never stripped it right back. My advice is
Remember it is Cast Iron and not steel so it does not rust in the same way as a car,it is a very slow process on cast iron. Do not strip off paint/ antifoul that is adhering well to the keel, just scrape off the loose bits and rub down to a sound surface and feather in the the surrounding A/F. I then used Blakes Primoncon, which was developed by Blakes specifically for this job of patching Antifoul on Cast Iron and Steel keels. If you contact the new owners of Blakes I am sure they can advise what the current product is called. As others have said you need to leave it a while before you overcoat with A/F or it bleeds through. It worked for me. I have seen alot of boats in our yard where the keel has been ground clean and then painted with very expensive primers etc and in a couple of years the A/F is flaking off again. You will never achieve the original primer adhesion as this was done immediately after shot blasting in the foundry, you cannot reproduce those conditions in a boat yard.

Good Luck
David MH
 
davidmh said:
I had a Trapper 500 for twenty years with a cast iron Fin Keel, and every year it developed a few patches of rust and a few bits of antifoul fell off. I followed the advise of the Technicians at Blakes in Gosport and just patched it each year, It was no worse when I sold it than when I bought it and I never stripped it right back. My advice is
Remember it is Cast Iron and not steel so it does not rust in the same way as a car,it is a very slow process on cast iron. Do not strip off paint/ antifoul that is adhering well to the keel, just scrape off the loose bits and rub down to a sound surface and feather in the the surrounding A/F. I then used Blakes Primoncon, which was developed by Blakes specifically for this job of patching Antifoul on Cast Iron and Steel keels. If you contact the new owners of Blakes I am sure they can advise what the current product is called. As others have said you need to leave it a while before you overcoat with A/F or it bleeds through. It worked for me. I have seen alot of boats in our yard where the keel has been ground clean and then painted with very expensive primers etc and in a couple of years the A/F is flaking off again. You will never achieve the original primer adhesion as this was done immediately after shot blasting in the foundry, you cannot reproduce those conditions in a boat yard.

Good Luck
David MH
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Primocon is International Yachtpaints'underwater primer:- http://www.yachtpaint.com/gbr/diy/products/primers/primocon.aspx

Blakes is now owned by Hempel and the current range of primers is here http://www.hempelyacht.com/en-GB/pr...?type=Primers-Undercoats-Fillers&boat=Sailing
 
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Derek,

It was not actually my boat but belonged to a friend. Lovely boat when you got her in the groove, often beat our way past much larger vessels in a chop. The boat got vandalised whilst we had her in the yard to do major deck repairs 0 trying to scarf patches into the ply deck. The toerags used such a long lever to get the companionway open, it seriously damaged the bulkhead. My mate sold her to another friend who lives in Hythe, so could get round to work on her every evening. He simply doublt up the bulkhead and replaced the entire deck - much quicker than patching and will last longer! She's still on a swinging mooring near the Hythe pier, last time I looked. Name of "Hasty" and built by D.C.Perfect with a bulbed cast iron keel, of course.

Rob.
 
PabloPicasso said:
Yes, don't treat rusty areas on your keel If you don't mind your keel rusting away to nothing, reducing your stability and righting moment, These things are not important to the average club racer or cruiser. And you can always get a two for one deal on new cast iron keels in your local Sainsburys or tesco.

So most definitely a waste of time money and effort maintaining your keel. As is servicing winches, scrubbing off, painting varnishing engine servicing, and many other yachting boat jobs. Your wife is probably correct. You're wasting time and money on that boat that's better spent in the house minding the kids and supporting her after a glass of wine online shopping habits

So, don't do anything about those rusty spots on the keel...
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You can also get these in Tesco/Sainsburys :) : www.snickers.com
 
A smooth keel gives much better windward performance.
A smooth rudder can steer much harder before stalling.
Anything un-smooth is drag, which makes your boat slow, heavy on fuel and dull to sail.

There are two alternatives to antifouling and so forth:
Dry sailing
Frequent hull cleaning. For serious racers, frequent can mean daily!
 
I have a similar problem with a Westerly as you - they used the same foundries.

I use this stuff before antifouling each year

http://www.amazon.co.uk/Aquasteel-R...qid=1450295303&sr=8-5&keywords=rust+treatment

I wire brush the affected areas, then coat one coat of this - then antifoul on top. It does not take long to do.

Over the years the amount of rusting areas has reduced - I think the treatment seems to last a couple of years before that patch rusts again.

To keep Vyv happy about the cosmetic look at launch - it always looks fine at launch:encouragement: - and not too bad at the end of the season.

I my view, its a total waste of time to try blasting and epoxying - I did that on another boat - and 4 years later was back to square one - peeling off large areas of failed coating!
 
Following on from this, I sprayed some "Rust-eater" on my keel yesterday and it had no effect at all, didn't even go black, though it did on other steel items. Sprayed on my rusty CQR shank and it fizzed instantly (zinc?)
 
Ardenfour said:
Following on from this, I sprayed some "Rust-eater" on my keel yesterday and it had no effect at all, didn't even go black, though it did on other steel items. Sprayed on my rusty CQR shank and it fizzed instantly (zinc?)
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Try the one I suggested above - works for me. I wonder whether the spray type puts enough on?
 
I tend to use abrasives to get the rust off, then use some sort of phosphoric acid based rust remover in the hope of getting into the pores of the porous cast iron.
Then apply epoxy, hopefully after a warm dry spell.
 
Chris_Robb said:
To keep Vyv happy about the cosmetic look at launch - it always looks fine at launch:encouragement: - and not too bad at the end of the season.
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Maybe a step further than cosmetic, this was our keel at lift-out after a winter afloat. Rust had got underneath the epoxy and Coppercoat and was having a field day. However, it was 11 years old so had not done too badly. Its replacement of the same treatment is now nearly 10 years old and still going.
P1010737_zpsadd3lxl2.jpg
 
zambant said:
That's exactly what I am wondering....forget how to protect it....is it really worth the effort ???
25 yrs and its still got loads of metal left......
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If the cosmetics bother you then a quick grind, red primer and hammerite. Im relaxed about mine!
Stu
 
I have noticed that my keel always comes nice and almost rust free when I haul out but it's after it's been exposed to air that the rust spots appear. I have been cleaning them off and painting over with epoxy paint for the last 15 years and it's actually getting better. My previous boat had a lead keel.Now that was good!
 
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