floor thickness question

[2cycle]

Hello all, I just purchased a 1972 18 ft. Cobia Sportster. The guy recently replaced the floor with 3/4 " plywood glassed over with bi-axial and polyester resin. It's not the greatest job in the world and there are a few small repairs that need to be made and I need to put a hatch over the fuel cell in the center. I'm thinking of weight, so would anyone recommend replacing the 3/4 with 1/2, and will the 3/4 add that much weight as compared to the 1/2? One pro to redoing it would be to check out the stringers and make sure everything is done right the first time. I like the idea of the 3/4, but I'm wondering if that will add needless weight when 1/2 would more than suffice. Any thoughts and suggestions are appreciated and the boat will be powerd with a Merc Inline 1500 (1975). Thanks!

 

[Boomyal]

Re: floor thickness question

Methinks that 3/4" ply is gross overkill. Makes me wonder if he was hiding anything? Half inch is perfectly adequate. Personally I would have done half inch with two layers of 10 0z cloth. I'm sure you'll get many opinions at least for the glass covering.

 

[Tail_Gunner]

Re: floor thickness question

Methinks that 3/4" ply is gross overkill. Makes me wonder if he was hiding anything? Half inch is perfectly adequate. Personally I would have done half inch with two layers of 10 0z cloth. I'm sure you'll get many opinions at least for the glass covering.

Agreeded 1/2" glassed and if cloth was used would make a almost indestructable floor....... umm especially if you use 9lb foam under it.....

 

[2cycle]

Re: floor thickness question

Thanks Boomyal and Tail Gunner for the replies. I think I erred in saying it was 3/4. It was actually 5/8. I'm leaning toward redoing it to my liking with the 1/2 and two layers of cloth so I can find out how the stringers are and eliminate weight.

 

[Bondo]

Re: floor thickness question

Unless there is some Other compelling Reason,.......

I Don't think that I would replace the floor for a 1/8th" difference......
In an 18' boat,..... That Might be 10lbs, or less difference.........

But,... I Do Agree,.... 1/2" Plywood is Plenty for a boat Floor.........