Iron Ballast

[GreggRuch]

I am considering buying a boat which may have encapsulated iron ballast. I am aware that this can cause problems with the iron getting wet and expanding.
Does anyone have any experience with iron encapsulated keels?
Is there anyone who knows if there is a way to determine whether a boat ballast is iron or lead if it is encapsulated?

[Sailmc]

I have three years into a boat with an encapsulated cast iron keel. So far I''ve had no problems but I am in fresh water for only 6 monthes of the year. No problems yet. You might try a magnet to see if the keel is in fact iron. If you are talking about a cast iron keel covered in epoxy you can see any problems as the surface will start to blister and rust will start to pop out. If the integrity of the finish is fine you should have no problems and a bit of maintenence at the first hint goes a long way. It would not be my first choice but so far has been trouble free.

[maxcontax]

My partner and I have a Beneteau First 345 (1984) with an encapsulated iron keel. In 20 years the boat has had more issues with osmotic blistering than with the keel. the keel being iron is a non-issue to us, hope it is the same for you

[Johnrb]

While I haven’t owned a boat with an encapsulated iron keel, I have seen a reasonable number of such boats when walking around clubs and marinas. Like Sailmc above, I too live on fresh water (Lake Ontario) and the boats I am most familiar with that have such a keel are the Alberg 30 and Contessa 26 (later versions of the JJ Taylor Contessa 26 had lead ballast which allowed the cabin floor to be lowered slightly). I haven’t seen or heard of the type of problem that you are asking about and both of the above boat types were produced in reasonably large numbers with an average fleet age of perhaps 30 years - or longer in the case of the Alberg. The Albin Vega also has an encapsulated iron ballast (with a lead shoe I believe) and I haven’t seen or heard of the type of problem you are referring to. About 3,000 Vegas were produced with a fair number having been taken offshore – again most were built in the early to mid 1970’s.

A separate issue that Jeff_H has discussed in length in other posts concerns the structural integrity of all encapsulated ballasted boats in case of a hard grounding. I would guess that a full keel boat could better withstand this than a fin keel.

[Billpjr]

I''ve owned three iron keel boats...one a bolt on fin with bulb, a full keel with internal cast iron keel glassed in and another with internal iron pigs sealed in concrete. All were 15-20 yrs old when I bought them and there were no problems. There are 1000s of old boats with iron keels and they are doing fine. I would not hesitate to buy another iron keel and go cruising with it.

In my opinion the scare about them is more hype than reality. Problem boats to look for would be home builts with incorrect installation methods and/or have internal pigs/punchings sealed in concrete that is too thin to keep moisture away. Like bridge construction, the concrete must be X inches thick to keep rebar from rusting and expanding. Rust will first show as bleeds or bulges.

[Jeff_H]

Bolt on cast iron keels are slighly more maintenance than a bolt on lead keel, needing prompt touch up to any damage to the fairing materials and barrier coat when ever the boat is hauled out.

Encapsulated iron keels, and especially encapsulated iron set in concrete keels should be avoided like the plague. My direct experience with them and my conversations with marine surveyors regarding them is that it is simply a matter of time before water gets through the encapsulation envelope, usually from the bilge, and that the rusting iron will slowly damage the bond between the encapsulation envelope and the ballast. Also over time, once rusting starts it will pry the matrix of concrete and iron apart so that the ballast keel is no longer a single casting. It would be nice if there was a proper concrete cover as Billpjr suggests but that cover would be required to be 3" (which is the concrete cover required above the steel for concrete in contact with moisture). Most boats that I have seen, do not have any concrete cover on the steel as the steel and concrete are mixed together in a cement mixer and simply dumped into the encapsulation envelope. This is a poor way to build a boat as the concrete shrinks as it cures and breaks the bonds with the envelope. Bristol used to cast its concrete and iron ballast in a separate mold and use polyester slurry to glue it in place. That is a better system but one that is rarely used in boat construction these days.

Once the bond between the keel and the encapsulation envelope is broken and once the iron starts to rust, there really is no econmical and good way to restore these critical bonds.

Respectfully,
Jeff