I'm looking at an '84 Hunter 34 with cast iron ballast. How real is the corrosion issue with this material in an older boat?
Cast iron ballast
- Thread starter Jwhy
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Cast iron has been used for decades primarily on European boats - today they are also used on some US brands.
We've had cast iron keels on our (4) boats for 30 years without significant problems. Any corrosion can be mitigated by cleaning, priming and applying a barrier coating. If the majority of the keel has issues - probably easier to soda blast the entire keel then prime, etc.
Be careful not to apply anti fouling paint directly onto a bare cast iron keel or where there is corrosion since the copper in the paint will further accelerate the problem.
We've had cast iron keels on our (4) boats for 30 years without significant problems. Any corrosion can be mitigated by cleaning, priming and applying a barrier coating. If the majority of the keel has issues - probably easier to soda blast the entire keel then prime, etc.
Be careful not to apply anti fouling paint directly onto a bare cast iron keel or where there is corrosion since the copper in the paint will further accelerate the problem.
I doubt that you will outlast the cast iron keel. There are still many boats that are built with them today.
Prep it, seal it and keep it off the bottom and you should only have minor maintenance every few years.
Prep it, seal it and keep it off the bottom and you should only have minor maintenance every few years.
It is a minor nuisance that we have dealt with through the learning experience. Fortunately for you that knowledge is available. In the 28 years we've owned the boat we have dealt with it maybe 5 times, and each time it becomes less of an issue. It was really never a big problem. Maybe in that time we've lost 3 or 4 pounds of ballast out of the 5000 pound keel. With the measures taken by us and the previous posters, the issue seems resolved.
Looking at the other merits of the H34, we have always felt the boat was a good choice for us...roomy, reasonably comfortable and reliable.
Looking at the other merits of the H34, we have always felt the boat was a good choice for us...roomy, reasonably comfortable and reliable.
I definitely agree with Allan, I would have preferred a lead keel but because of the other benefits of the boat, the iron one was not a show stopper. I usually do my own work so it has not been expensive to maintain. The key is to not let it get out of control. once it is properly primed and sealed, maintenance is very reasonable.
Check the history of this boat and it owners. http://forum.woodenboat.com/showthread.php?72540-Tim-and-Pauline-Carr-Curlew
Curlew has a cast iron keel and is far older that any of us.
Curlew has a cast iron keel and is far older that any of us.
My Meridian was built in 1961, with a cast iron keel. Still sailing today, just fine.
My 1972 Lindsey 21 footer has a cast iron keel also
I ground to bare and coated with coal tar epoxy (tip- it stinks). The 21 in 1999, the Meridian in 2004. Both are still good to go, although the Meridian now needs a touch up in a few spots.
Coal tar epoxy is used on offshore oil rigs and platforms to retard corrosion- good stuff . You can bottom paint right over it too.
Did I mention it stinks while uncured?-grin.
My 1972 Lindsey 21 footer has a cast iron keel also
I ground to bare and coated with coal tar epoxy (tip- it stinks). The 21 in 1999, the Meridian in 2004. Both are still good to go, although the Meridian now needs a touch up in a few spots.
Coal tar epoxy is used on offshore oil rigs and platforms to retard corrosion- good stuff . You can bottom paint right over it too.
Did I mention it stinks while uncured?-grin.
Rust is virtually guaranteed and nothing you do is ever going to eliminate it completely. That being said, it shouldn't be a deal-breaker if the boat has been well maintained. Very common issue on many thousands of externally ballasted keels.
Glass Over Iron?
You know, what I never hear about is glassing over the keel. I had a 26' T-Bird for 19 years that had a fiberglassed iron keel. I had a bubble on it once and I just ground off the area and reglassed it. No big deal. Wonder why more are not done that way?
As big of PITA iron can be it would seem what Beneteau has done with the bolts being able to be removed one at a time for service WITHOUT the drama of removing the keel is a pretty fair tradeoff
If nothing is going to stop rust, then it makes you wonder how these offshore drill/pumping rigs can be in salt water for 20-30 years or more.
Is there any reason to NOT use coal tar epoxy and fiber glass to enclose an iron keel? I believe that with some careful planning you could apply enough glass and epoxy to effectively change an external ballast keel to an internal ballast keel.
Cast Iron Keel Maintenence
I have a cast Iron keel on my 1975 pearson 26w Ive owned it since 2000 with minor touch up`s to rusted areas using pettit rust inhibitor. At the end of last season after haul out I noticed large sections of the original fiberglass coating on the keel had literally fallen off.
I hired someone to scrape and peel of the rest of the glass coating down to the bare cast Iron (Im 75 with a bad back. I didnt feel up to it). After the keel was down to bare iron I washed
it down with a solvent. step 2 I applied 2 coats of pettit 1 part rust protector. Step 3 I applied 2 coats of west system epoxy. And finally 2 coats of ablative bottom paint.
I have a cast Iron keel on my 1975 pearson 26w Ive owned it since 2000 with minor touch up`s to rusted areas using pettit rust inhibitor. At the end of last season after haul out I noticed large sections of the original fiberglass coating on the keel had literally fallen off.
I hired someone to scrape and peel of the rest of the glass coating down to the bare cast Iron (Im 75 with a bad back. I didnt feel up to it). After the keel was down to bare iron I washed
it down with a solvent. step 2 I applied 2 coats of pettit 1 part rust protector. Step 3 I applied 2 coats of west system epoxy. And finally 2 coats of ablative bottom paint.
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