After reading Sue & Larry's article on drilling holes, I'd like to know what epoxy they recommend and what type of bevel should be ground around the hole?
Sue and Larry respond:
We use the West System epoxy resin. Mixing the epoxy resin with the hardener is a very crucial part of the process and the West System makes this simple by having pumps that take all the guess work out of it. We learned this the hard way thinking we didn't need to buy the pumps and that we could measure it ourselves by hand, but soon found we were making mistakes, and quickly became one of the converted. We've been told by boatyard workers that many of the epoxy resin brands are made by the same company, but we can't guarantee this to be true.
Any and all core material should be sealed with epoxy after drilling a new hole and before the fastener is inserted, even though the hardware will be bedded in a sealant.
The bevel that is ground around the hole should be with the widest area on the top surface. Gougeon Brothers, the makers of West System, recommend a minimum 12 to one bevel to best create a bonding area for the patch. For example, if your hole is through a 1/4-inch-thick laminate, the outer edge of the bevel will extend three inches from the inside edge of the hole. In truth, we can't guarantee that all of our bevels are 12 to one, but they are none the less beveled quite a bit to better receive the epoxy.