CHARLES wrote: > The number of layers needed is driven by the weight of the cloth chosen > and how thick the hull is there. I'd use 1708 as it is so easy to work > with. It's two bias layers of 8oz roving stitched to some 1 1/2 oz glass > mat. Measure the thickness of the hull after removing the thru-hull. > Multiply that by 12 to mark a circle around the hole. Then grind a bevel > from the hole out to the mark. Cover the hole from the inside with some > mylar sheet, taped tight to the surface. > > I've done a number of these and always lay up a layer of glass on the inside -- instead of taping mylar as Charls suggests -- and let it set before working from the outside. Just makes me feel better that way. Other than that, I pretty much follow his suggestion as written. But then I grind it after it sets just deep enough that I can fill and fair with a thin layer of gelcoat. I usually like to work with WEST epoxy, but gelcoat doesn't adhere well to epoxy, so I use polyester resin for those jobs.
Jim Hesketh C&C 26 Whisper Miami, FL
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