Re: Paint Remover for anti-fouling paint
A few years ago I decided to use a soy based stripper instead of sanding/scraping. I needed to get all of the old pain off so that I could put on a barrier coat. The soy stripper would strip about one coat of old pain at a time, not the several layers advertised. So at that rate it would have been far too expensive to get down to the gelcoat. I eneded up sanding the last few layers which were very hard and well adhered to the gelcoat. One of the problems I encountered was that it turned very warm after I hauled the boat and the stripper would dry out before penetrating several layers of paint. If you have a nice overcast sky and less that 80-85 degrees I'm sure stripper will be more effective than in my experience.
Be careful with disc sanders and sharp scrapers with pointed corners as they easily gouge the gelcoat once you are through the paint. Also, they are very tedious in those complex compound curves around the rudder and keel. I would grind down the corners of any scraper I use in these areas.
Make sure the stripper you use is good for fiberglass and follow the directions carefully as many strippers have the potential to soften the gelcoat and maybe even the substrate.
Its a nasty job any way you go about it, but with stripper it is much easier to control what gets onto your skin and into your lungs.