I need to build a new engine hatch for my boat. My old one has the middle cut out so the motor would fit up thru it. It is not really repairable but is OK for a template. My question is how do I build a new one? I want it to be flat with an upostered pad on top and the underside to look good. Do I use 1/2" plywood and cover it in fiberglass one layer and then have the pad made for the top. I want to keep it light yet strong enough to walk/lay on.

I built one for an old Formula I had. I didn't cover it with glass, but did use 1/2" ply with stiffeners on the bottom. I was doing it as cheap as possible at the time so covered it with cheap carpet. It did hold my 200# nephew tho.

marty,

1/2 in. plywood is ok but you can also use 3/8 for weight savings. i would use more like 4 sheets of woven fiberglass cloth, not matting. it will be much smoother. do the underside also so it won't rot and you won't have to pay for marine plywood . when you lay up the fiberglass you can use a laminating resin so there is no sanding between coats. then a regular resin for the top coat. color can be added to either resin if you don't want to paint it. the final coat of resin on the topside should really be poured on and spread out to get the smoothest surface.

I am sure that Glassdave will step in hear and set us all straite sooner or later. HOWEVER I would take what you have and either fix it (fill in the hole) or if you went new I would go with a layer of glass then a layer of end cut balsa then glass again. The balsa will save you LOTS of weight and still give LOTS of gigidity that you need. You will also need to add some reinforcing stips but that is easy enough if you can pull off the rest of it

Jon

You should also look into Klegecell. It is strong and light.

Go here:
http://www.fgci.com/

And check it out.

Marty,
I just completed my engine hatch. I used 1/2" ply wood thoroughly resined on both sides and more importantly the edges of the plywood. 2"x2" stiffeners are attached on the bottom to give strength to the hatch. The stiffeners, hinges and actuator brackets are attached using stainless steel tee nuts. As opposed to painting the underside I chose to cover with a matching vinyl. The edges of the vinyl are covered by an upholstery edging I purchased from an upholstery shop. And of course use stainless steel staples. I purchased these at Home Depot.

Good luck
Paul

I have a flat deck hatch off of my existing boat that won't work because the engine is too high. Any interest? It's a flat deck but doesn't have the stiffeners that PB mentioned. Because those are missing, it's rather flimsy.

Thanks everyone. I like the products from FGCI and trying to find out more or its like suggested 1/2" ply either bilge painted or glassed around and then upollstered. Great help. Thanks.