I've gotta replace my hatch cover, its rotten. Its fairly large, approximately 7' wide X 4 1/2' back to front. I'm concerned about the weight of the starboard and cost vs using plywood. The existing cover is mainly 3/4 plywood as a base with more plywood on top that is used to attach the upholstered pieces. Also how does the strength compare? Could I use a thinner piece of starboard than the plywood to save weight? Are there any other products out there simular to the starboard that I could use. I don't want to get into a lot of glass work on this project. HELP!

do a search for threads by cuda--he posted a good thesis on similar project with lots of pictures.

I'd use starboard. It will olast longer, not absorb water and cost really isn't that big an issue. There are other name brands of HDPE and sources are in that same thread.

I just redid mine with starboard, but I had a fiberglass shell under it for support. I think if you did it in starboard, it might sag when it gets hot. The last time I was at the plastic place, he showed me some pvc board. I think it would work better. It's stiffer, lighter, and cheaper. I took a scrap home with me and set it in the sun to see if it would sag, and it didn't.

Cuda....where would I find the PVC board...hadn't thought about the starboard sagging....thats why I need so much help....Skip

If you want to save some weight u can do your hatch out of fiberglass with a balsa or similar light weight core material and use a blown plastic/pvs product like starLIGHT not starboard for the upholstery backer.

Using a solid piece of starboard for a hatch that size WILL be heavy and expensive and not very good. It just doesn't have the stiffness your going to want.

You could always go back to a thinner plywood and laminate both sides with fiberglass. So it will resist water infiltration and if you finish it out correctly with gelcoat it will look great too.

You can get it from Farco Plastics in Orlando. They might know someone closer to you that carries it. There is a Farco in Clearwater also. The one in Orlando had some special cut boards that a customer went out of business. I forget the size, but I was thinking they were big enough for me to make a hatch from. I think he was trying to blow them out for like $56 a board. I'm thinking they were 5x6, but not sure. I think the full sheets in half inch were about $90.

PVC type sheets (like 4X8) can be bought at any sign supply business. Call your local sign shop and ask where they buy their materials. The last time I bought some it was less than $100 sheet and the place had 2 or 3 different types.

I used decolite balsa ,I think it was 1'' We put a pro stock scoop in it , MRV8OUTBOARD JEB walked me through it ,HE'S THE MAN. He built his race boat from scratch 28ft concept. twin o/b my hatch is 9yrs old light weight.

I bought a sheet of pvc board last week. I'll let you know how it works out.

Cuda - how thick is the piece you bought???