Do I [b]need to do anything else to the seam first?
Unlike Boler, Scamp, Casita
, et al., I don't consider it a "seam" per se.
The fore-mentioned brands joined two halves of their bodies that does leave a crack between two "lips" on the outside,
while fiber-glassing the seam over on the inside.
The "lips of the body"
are then covered with a decorative trim. For comparison sake, I will refer to that crack
as an "Innie", as in an innie belly button.
on the other hand, molded within a split mold that was all clamped together before the fiberglass was applied to it. That area is merely the [b]remnant of a ridge where the gel-coat seeped into the crack between the lips of the mold.
I'll refer to that ridge
as an "Outie", merely an unavoidable blemish on an otherwise smooth single surface. The manufacturer just sanded the ridge down to almost flush
, but didn't sand further to avoid damaging gel-coat in a wider swath. He then covered it with a decal stripe, which still telegraphed the bump behind it, but didn't consider it a defect at the time. That area [b]will not leak.