Encapsulated iron ballast question

[contessaman]

my boat has an encapsulated iron keel. At her pre purchase survey the surveyor reported no sign of any rusting or swelling. Less than twelve months later I had her ashore and discovered by tapping with a plastic hammer, a fairly large repair to the front of my keel (approx 8" circular) which had been made entirely of filler and was in poor condition. I set to work with the angle grinder and opened this out . there was some evidence of delamination to the immediate surrounding laminates so this was also chopped out then I tapered well into the GRP over around a 5 foot area. There was evidence of some rust coloured water from the keel. No visible drips but with the keel 'open' some rust streaks would ooze/ appear when I returned to the boat. I dried it all as best I could given the time of year and made my repairs alternating CSM and woven rovings before fairing, building up a layer of gelcoat once more then touching in epoxy paint just like the rest of the hull has.

Boat has been back in the water for a year and just come ashore. All looks solid and sounds sharply when tapped. No swelling. No cracks. All good.

Question is... Do I drill a 'drain' hole in case there is still some trapped moisture ( ideally when making the above repair I'd have had longer to let it breathe but I only had a few months ashore) .

Or..

Since the repair seems very solid and sound do I accept that with a boat of my age there will always be a little moisture in there. If its all solid and sealed, iron shouldn't rust without oxygen... Do I leave well alone?

Grateful for any advice.

Ta

 

[KellysEye]

If it looks good I would leave it alone.

 

[oldharry]

Agree. If it aint broke, dont fix it! Drilling a drain hole wont enable the casing to dry out, and would readmit oxygen which as you say would accelerate rust. Personally, having done the repair I would leave well alone, and check as you have each time she comes out.

 

[Steve_N]

I've been down the same road with the encapsulated keel on my 37' Countess. Upon purchase there was a visible repair, a very big one, to the leading edge. The repair had been done by a Spanish boatyard but was visibly sub-standard and like yours it turned out to be mostly car filler on top of some very poorly wetted-out CSM. Rusty water continued to drip out over a number of weeks and it seemed like it would never dry completely so in the end, when it was down to just producing the odd drip or streak over time, I just went ahead with the repair. In my case it has been fine and 12 years later the keel and its repair remain sound.

I guess it will depend on the nature of the ballast and how well it's encapsulated though. At the same as I was doing my repair there was an owner of a much more prestigous brand of yacht doing a similar job in the yard. When he removed the damaged laminate the ballast itself began pouring out onto the ground and he could reach up inside the void and scrape out handfulls of rusty iron shot. Quite a mess and nothing like mine where the ballast was well encapsulated in resin.

 

[Tranona]

Water getting in from the bilge is quite common with encapsulated keels, but not really a problem with a solid casting. like blood it takes very little water to make a lot of rusty stained drips. The problem ones as already suggested are where the ballast is shot, punchings or lumps of iron encapsulated in resin as there is a very large surface area that once it starts to rust expands and can eventually break out of the GRP casing.

So, agree with others, leave well alone.

 

[contessaman]

Thanks guys you've confirmed my own thoughts. Pretty sure my boat (HR38) is a solid iron casting not shot or punchings. Perhaps I will email them to confirm. And ditto exactly as Steve has said above about thinking it would never really 'dry out' so I just had to go ahead and repair it. Its annoying that some so-called professional boat yard had repaired this dink with car body filler and a layer of CSM. Its the keel for goodness sake! Any damage should be repaired properly. I can just picture the guy doing it in the Caribbean now..with a big reefer hanging out of his mouth as he trowels on the P38.

Hopefully it'll be fine for a decade or more like yours too.

Just goes to show no type of keel is 'perfect' they've all got their shortcomings.. especially if one isn't lucky enough to own the boat from new and has to buy a used one with skeletons in the closet!

Cheers