In this article we will discuss the benefits of having a cast iron sailboat keel vs the benefits of having a lead sailboat keel. Keep in mind we are keeping it very simple here.
- Lower center of gravity, as lead is very dense and therefore heavy. Twice as heavy as iron but taking up the same amount of space.
- Lead is less corrosive than iron. Will not corrode internally as iron will.
- Some say lead has better performance.
- Grounding energy transfer tends to not deform the hull. It simply deforms the keel or bulb, Which is relatively easy to fix.
- Much stronger than lead. So if you hit something you will most likely plow right through it i.e coral reefs.
- Iron keels have the advantage of having removable and replaceable keel bolts whereas lead keels must have radical surgery or be re-cast to replace corroded bolts.
- Much cheaper than lead, due to environmental concerns and other factors.
- Will not chip away during impacts. The repairs are fairly simple.
In summary if I had to choose between the two options I would choose iron for the simple fact that it has low maintenance if you properly prime and paint the iron correctly. Iron also is very strong so if you hit little things here and there (which everyone does at some point) its not going to mess up your sailing due to the fact that iron does not deform on impact. Others have indicated that lead absorbs some impact on grounding. My opinion on this is that if you are grounding a sailboat the keel is not absorbing anything in fact if the same boat with two different types of keels grounded exactly the same. The same result would happen..a damaged hull. So that argument comes down to how hard you hit.
I also would choose iron because the benefits of lead do not out weigh the cost of lead. Simply put, I do not see enough difference between the two to choose the more expensive option of lead. I have inspected many iron keeled sailboats and rarely see major damage on them to sway my opinion. There are many arguments online about this subject, as many people know sailboat owners are very passionate about their vessels almost to passionate to the point where they miss the simple facts. The difference between the two simply comes down to designer preference and ballast differences. Both are working viable options that serve one purpose. A buying decision should not be made on one or the other.
Author: Principal Marine Surveyor
SAMS®, ABYC, AIMU