I have a 15 year old foam sandwich catamaran
, the laminate being glass/polyester resin. After extensive renovations on the boat, I decided to apply an epoxy
barrier coat to the hull
followed by Coppercoat.
Originally, the boat had very few blisters
, and a moisture meter showed the hulls were pretty much dry. I had wet areas to deal with on the topside and deck
, so I am familiar with what the readings of my (Tramex) meter mean.
I sanded the gel coat with 80 grit paper, washed it with water
and then acetone, and then applied 4 coats of Leigh's Epigrip L524. I applied the Coppercoat and sailed south from the UK, and I'm now in the Caribbean
. I first noticed blistering in the Canaries
, and it is now extensive.
I haven't yet taken the boat out of the water
, but chiselled away some blisters
and found the gel coat coming away from the laminate (most blisters 2-3mm diameter, but some 10-15mm).
I'm puzzled - the hull
originally had no blisters. Now after coating with epoxy
, the boat is riddled with blisters. I used the same paint
as an undercoat on the topsides and deck
, and there are no problems there - it is very tough and resistant to abrasion.
Any suggestions as to what has gone wrong and how to fix it? I'd like some idea before I take it out of the water again.