Drilling a Hole Into a Cored Hull

[Roniszoro]

Hi All;

I want to install a dynaplate on my cored hull. This, of course, needs to be at/near the bottom of the hull, well below the water line.

I have been told that two approaches are: drill a bigger hole than needed, fill it with epoxy; let it dry and then drill the smaller hole needed in the epoxy area OR drill the hole size that you need and then rout out the core around it within the outer and inner glass surfaces and fill that area with epoxy. Each method will allegedly prevent water from getting to the core.

Your thoughts or another way please? Thank you.

[wholybee]

If it is a fitting subject to stress and movement drilling the proper sized hole and routing out the core is probably slightly better. I doubt there is any difference for a dyna-plate which will never move.

I split the difference. I drilled the hole size i needed. Then from one side drilled a larger hole through the core but not all the way through the glass on the other side.

[CarlF]

I've done Warren's method with the small hole on the outer hull. Be extremely careful to clean the inside of the fiberglass so that the epoxy gets a good bond. A small bonding failure will let the water sneak in between the fiberglass and epoxy. The water is under pressure (below the waterline) so it's hard to stop. Make the big hole at least 1" so you have good access.