I used to cover with paper and wood glue (PVA), then foam doesn’t melt.Hey Hussein, What specifically are you asking about reinforcing the fiberglass?
clark starts the thinking process.........
The truth is I haven't really thought about how I was going to do that yet . I need to protect the polystyrene from the resin so it doesn't just melt away so I was going to paint as Karl suggested. I have been wondering about just glassing it all around and allowing the foam thickness to increase the structural rigidity similar to a core mat. But if the fiberglass isn't connected to the foam and there aren't places where it connects back to itself I am not sure it will have the desired strength - so that is out. But if I just throw a wack of glass down to make it stronger then the weight is going to increase significantly - so that is out. Core mat has a bunch of holes to reconnect the resin between layers increasing the thickness but not absorbing the resin so it keeps the weight down. Perhaps I can strategically drill a number of 3/8 holes before I paint and it can have a similar effect? ..... thinking..... rethinking....... I'm leaning toward that option at the moment - the honey comb effect.
So ... there's my current plan