Here is a technique I use to shave off at least a pound. I always apply a seal coat of epoxy to the bare wood. I use System 3 and about 40 minutes after applying, I squeegee all the excess off. And I mean really clean the excess off. (At 40 minutes the wood has absorbed all it is going to absorb because the epoxy is starting to gel.) I have a flexible rubber squeegee that works really well on curved surfaces--black, about 1/8-inch thick--and a very flexible plastic auto body bondo squeegee that works just as well on flat surfaces and is a little easier to hold.

24 hours later I give it a once-over with a scraper to get all the fuzz and pimples off. I scrape because it is fast and doesn’t grind grit in like sanding does.

This technique does several things. 1. Minimizes weight. 2. Takes out any bubbles in the seal coat. 3. I don't have to fuss over a thin seal coat. The more I work to have a thin coat, the more bubbles I get. 4. Good surface for the fiberglass layer.