HELLO THERE

Yesterday I installed a Hobie Bob on the tip of my mast. while installing the rivets some little (1/4") cracks occurred from the pressure of the rivet gun. I think that if I take a spill the impact may actuallyrip the rivets off at these cracks. Is there something I can use to fill these cracks and strengthen this area?? maybe some kind of compound? also, should I seal around the rivets with something so that water does not go in??

thanks

fred
Hobie 18