that top must weigh a ton now.I just did mine. I’ve worked with both, in fact I started with epoxy and ended up starting over with polyester. I’m glad I did. I ended up reglassing both sides of my roof. I was astounded in the end that I went through four gallons of resin, which up here anyway, is over fifty bucks a gallon, plus methyl ethyl ketone catalyst. West System epoxy was about $110 per gallon plus more expensive catalysts. There are also compatibility issues when it comes to finishing, gel coat,etc.View attachment 2263429
My thought too. But it eliminates the need for a roll cage. Seriously, yes, it’s a little heavier but still pretty manageable and very strong. No oil canning. I can stand on top, no problem. With a small outboard motor clamped on, it doubles as a small boatthat top must weigh a ton now.
Basically what I was going to say.Epoxy resin has better adhesive properties, tensile strength and stiffness, resistance to micro-cracking and fatigue and more resistant to degradation from water ingress, ie. osmosis.
However, for the top of a 40, a basic polyester would be absolutely fine - structural FRP is my day job and quite frankly, very rarely do we need to go to an epoxy resin, in 90+ % of situations, a polyester or vinyl ester resin is suitable and besides, polyester resin and MEKP catalyst will be the most budget-friendly