Layering Fiberglass. Knowing when to stop

[Southern Pete]

Originally Posted by bruceh

One technique learned in A&P school is to get some of the small plastic scrapers they use for basic spreading of Bondo on auto bodywork. Cut it to the size you need and use it to press and scrape on the plies after you fully wet them out.

Yes, but... be careful. Heavy use of a scraper will drag fibres out of the surface of the cloth and lead to bunches at the edges. I prefer a steel scraper. Resin ratio is not at all critical on a fairing, to the extent its not worth measuring. Use the minimum resin to wet out the cloth thoroughly, then use peel ply and suck out as much as possible.

[bruceh]

I wasn't implying that you need any significant pressure with the scraper to see if there was excess resin on the fiberglass. Yes, be gentle and don't tug on the fibers to bunch them up.

Also, I agree that peel ply is essential on any layup. It does create a nice finish that can accept more layers if needed, and it makes a better surface for sanding and micro additions to get a nice finish.