Keel Joint. Expoxy or Caulking

[Seekswind]

Speaking with the local Marine Store about the keel/ hull joint. It was mentioned instead of epoxy and fairing that most people use 5200 caulking and then paint over. This is due to the fact that as soon as the boat is hauled out the weight of the lead keel will sag and potentional cause cracking in the fibre glass because the epoxy will bond and not have much play. Any thoughts

 

[capt.m]

yes..

I did this on my Pearson 26. 13 years later when I parted with the Pearson and welcomed my O'Day, the keel hull joint was fine. Used about 2 tubes of it if I recall.

 

[Dave]

Lead keel forces

When the boat is hauled the load on the joint will be in tension and distributed by the area of the joint. If the keel bolts are properly torqued you should not see any substantial "sag" of the keel. Your comment is really related to ductility of the materials. Epoxy will be brittle and caulking very ductile. I believe if you did a force analysis you would find that the forces on the keel joint will be much higher when the boat is heeled over and there is a bending moment applied to the cantilever beam keel. So if the joint is cracked it is much more likely from those forces than from the static force of the mass of the keel when the boat is hauled. I recommend torquing the bolts while on the hard since the joint will be in compression and the torque on the bolts will not have to overcome trying to lift the weight of the keel.