Restoring an old GRP hull, it was suggested I use Brushing Primer as used in the Auto Trade - this appeared to do the trick fine and smoothed back nicely and filled minor gremlins
I then applied Halfords Acrylic car spray paint over the primer a couple of days later.
Left it to dry 24 hours and started light sanding it ready for the next coat, and it lifted / cracked apart very easily in places but not everywhere.
Was this a compatibility problem, first coat of paint on too thick or something else do you think ? - I was using 600 grade wet and dry to sand it
As a possible solution I was thinking about painting GRP resin over the hull and sanding smooth then start painting again - will acrylic go onto resin and should a primer (normal) be used.
thanks