Bottom paint flag coat theory vs. reality
I've read in several books, magazines, and forum posts that when applying ablative bottom paint it's wise to apply an undercoat of a contrasting color to act as a "flag" to indicate when the topcoat is worn through. I'm curious as to what kind of experiences people have had with this method in the real world?
Looking around boatyards at boats awaiting spring painting, I haven't seen boats with half worn-through top coats revealing contrasting color paint. In my own experience, the ablative paint loses all effectiveness and must be recoated well before it wears off. In the interest of minimizing paint buildup, it seems that it might be better to skip the flag coat and and to just apply single thin coat of ablative directly over the barrier coat.
I'd appreciate people's thoughts and experiences on this. I just had my boat's bottom soda blasted and plan to barrier coat in the spring. Since I'm starting over completely I want to do things right and keep from getting to the point of having the extreme buildup I had before.
Beneteau Oceanis 400
formerly Lippincott 30