Matt—
First, it would help if you said what boat you have, as there may be issues specific to the make and model of boat you've got.
Second, not a good idea to use epoxy to re-bed the keel, especially, you'll probably have to drop it again in the future, and bedding it with epoxy will make that really an interesting, in a bad way, task.
Third, 5200 isn't necessarily the best choice of sealants to use. 5200 has an adhesive strength greater than the underlying laminate and is very difficult to remove, again causing any future re-bedding to be more interesting than it should be.
It is also not as elastic as some of the other sealant, that might be better suited to the task.
You should also inspect the keel bolts for any corrosion damage, since bolts that have sat in salt water for extended periods of time can easily be eroded away by corrosion.
in your Application section, I believe you mean KEEL not RUDDER.
Bonding the rudder to the hull would be a bad idea generally.
BTW, most hull-keel joins are faired, but not glassed over. Glassing over the join can seriously complicate repairs.
I'm sure that Maine Sail will be along with his recommendations on what sealant to use, probably SikaFlex 291 or something like that...
I'd highly recommend you read the
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