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Re: Strip: Ready to seal coat Night Heron *PIC*

The deck is fully sanded and "ready" for a seal coat.

At the Boat Shows I attended in early 90s, I noticed some of my boats and the boats of other builders exhibited what I call "silver fleck" in the fiberglass when viewed from a certain angle in full sunlight. My conclusion was the fiberglass was not TOTALLY wet-out. I suspected the one step, dry wood and fiberglass wet-out method was starving the fiberglass from getting all the resin it needed to be transparent (fiberglass is indeed glass) since the wood was pulling resin in the opposite direction to absorb all it could.

No one else seemed to mind or even notice this "silver fleck." I talked to several boat building epoxy makers and they said they painted over their epoxy, excepting the few who made strippers.

I noticed Ted Moores never used a second layer of fiberglass over his stems or hull deck joints because this was visible as a cloudy area on the boats of others who did. Few people probably realize Ted's laminated stems and sheer clamp methods to join deck/hulls were to avoid reinforcing these area with fiberglass.

I came up with the idea of a "seal coat" to separate the struggle for resin between dry wood and fiberglass.

What I did not know at the time was how different each epoxy brand is.

I was using System III (before it became System Three) epoxy which has a very long "green stage" and can be recoated for up to 72 hours and still have a chemical bond. So it worked very easily for a "seal coat" because I could apply the seal coat one evening and then wet-out the fiberglass the next night without having to sand.

Only much later, I learned other builders were having to sand their seal coats because their epoxy brand had a very short green stage.

So, before you start, it's important to know how long your epoxy brand's green stage lasts.

If you must sand your seal coat, you must do so only lightly. All you need is to rough the surface slightly for a tooth so the new coat of epoxy can mechanically bond to the old.

If you sand green epoxy too vigorously you'll smear the epoxy which will look whitish because air in being introduced. Imagine sanding a "Gummy Bear" if you know what those are.

Water is a solvent and is the best one to clean a surface to be coated or recoated with epoxy. A damp cloth over bare wood works well to remove dust.

As Jay suggested, working the the hull bottom gives you good epoxy/fiberglassing experience in a part of the boat which forgives sins.

There are a LOT of variables that each builder must deal with when working with epoxy/fiberglass. Brands, temperatures, and work methods have a great impact on results. If you are aware of these issues you can use them to your advantage instead of rolling the dice.

For more information on working with epoxy see -