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Discussion Starter #1
Hello All,
I am in the process of evaluating a couple of older boats and one has an iron keel. I have two questions.

First are they hard to maintain? I would keep the boat in salt water, probably year-round.

Second, can a handy DIY person replace keel bolts if needed?

I don''t mind the work but I like sailing a lot more. Thanks for any help.
 

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Maintaining an iron keel is harder than a lead keel. Depending on the particular boat, as a bread generality the surface of a cast iron keel without fairing material tends to be pretty lumpy and far less fair than lead castings. If you use an epoxy based fairing material and barrier coat, the fairing material can last a lot of years. That said, inevitably you will get a small ding in the epoxy and before long the adhesion will go down hill. The problem is far worse with polyester fillers but they are easier to fair.

Keel bolts replacement difficulty depends on the way they keel was bolted. If the keel has a flange, and the bolys run into the flange (typical for early iron fin keelers) it is quite easy to replace the bolts. But if the keel is conventionally through-bolted its a real bear. I have done keel bolts on a Folkboat that I owned in the early 1970''s. It was the single most difficult job that I have ever done on a boat. That said 2 of the 6 bolts came out without fuss or fanfare. One came out quickly with an impromised puller. The remaining bolts needed to be drilled out which was weeks of very hard work. In those days it was believed that there was no way to get adequate grip between a bolt and cast iron. Today you occasionally see reference to being able to drill and tap the cast iron and then epoxy the bolt in place. (The epoxy is used to consolidate any defects in the cast iron.) I have seen reference to needing to tap and drill as little as 12 bolt diameters and as many as 20 bolt diameters to achieve the full strength of the bolt for stainless steel to cast iron. Of course once you use epoxy you can''t replace the bolts again. If you plan to keel this boat for anything approaching 20 years I would give serious thought to installing monel bolts. Otherwise I''d use stainless steel.

Good luck
Jeff
 

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Discussion Starter #3
Jeff, Thanks for the info. Good stuff. It begs another question. If I don''t fair the iron keel will the performance be significantly affected? I don''t expect to race but I would like to get where I am going sooner rather than later.
Mike
 

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There''s two problems with not fairing the keel. The big one is paint adhesion. There is no way to properly sand the bottom paint when the keel looks like the craters of the moon. Sooner or later you end up sanding down through the barrier coat, sooner rather than later you end up with major peeling paint.

The performance thing depends on the the type of boat in question. Obviously, you will give up a fair amount of light air performance, some beating ability, and will also seem to be more tender in heavier air, but in moderate reeching conditions I would imagine that the increased drag would not seem all that apparent.

Jeff
 

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My boat has an Iron keel. I had it sandblasted,to refinish it and to my dismay all the previous fairing was also blown away in the process leaving a realy ugly casting with lots of marks and irregularities. But the solution to this problem was very simple. The few largest dings were roughly faired with an epoxy filler, and without delay a thick coat of Interprotect 3000 was applyed with an airless spayer. A quick sanding followed by another application of interprotect 3000 made an outstanding job. The Interprotect 3000 is a thick non sagging epoxy filler that is easy to sand, with good gap filling property. It is also a good barrier coat preventing rust, but a bit expensive. My keel never rusted again.
 
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