Keel / Hull Joint Rust

[picardy]

I have an Elan 344 which has some rust coming from the keel / hull joint. I have read various other threads which have been helpful and indicate it is nothing to worry about but have some specific questions

1. How do I remove the sealant
2. What process do I go through to treat the affected area prior to re-antifuling.

Many thanks

Photo below if it helps




http://www.ybw.com/forums/attachment.php?attachmentid=15165&stc=1&d=1324233426

 

[Jaramaz]

Just joint?

There will always be movements in the joint, as the two materials have different expansion coefficients. For the rust you see in the picture - start with a knife, hae an angle grinder ready.
There is some rust just below. that might be as the rust has spread a bit. Then you must use an angle grinder -start with a knife!

In my exerience the rust visible on the picture is comming from the same area, which may have extended a bit from the joint.

Grinding down to steel is a good thing. Do not make this excessive, stay in the are that has been attaced by rust. Be ready to clean with good solvents, and then to paint immediately.

Your question is maybe what paint to use? Many would recommend epoxy. It usually works well, but need time and temp to cure. There are other paints that could be considered. Depends on what has been used on the keel earlier on.
Paint can be applied in many layers: 3-15 depending on paint.

Do not do this work too early, as
temp must be good enough for the paint
Further movements should not destroy your nice work.

An alternative way is to relax a bit. Actually, rust grows very slow. With a knife one can smooth the area somewhat, and then put on the ususal antifouling.

 

[vyv_cox]

The question to be answered is whether there are similar stains inside the boat? This would indicate that the breakdown in the sealant has reached the keel bolts. In that case rebedding the keel is indicated.

Next question - does the gap between hull and keel open up when the boat is hanging in slings? If so there is little point in trying to clean and seal your rust, as the sealant will inevitably fail once the gap opens. In this case you could pay to have the boat hanging for 24 hours while you reseal it, but this may not do much other than improve the appearance.

If the gap doesn't open with the hull lifted then you may well be able to hold the rust back for a while by cleaning out the joint manually, then resealing. I would use a soft sealant as there is obviously some movement here.

 

[Halo]

Agree with all that has been said earlier
I dont think you will ever stop this without some major work - probably better just to contain the problem as follows (I had a similar situation on my previous boat and the following worked for 25 years).
1. Work on a dry day and (wearing DUST mask) use a knife to clear out stained area then wire bush to remove any loose material
2. Use KuRust on keel
3. Paint KuRust
4. When paint is dry run a good bead of sekaflex round joint
Repeat annually
Hope this helps
Martin

 

[picardy]

All comments much appreciated many thanks