3/8" plywood will work....you could use marine wood, but youre looking at around $80 a sheet ....verses $15 per sheet for the regular stuff at home depot

its the same old story......money saved vs doing it right.

good points GAWnCA 

I have an interior project coming up very soon that i will document everything i am doing and post it up on the site. it should start later this week.

-brad

...  Now, how can I get that paint booth reserved where you did your boat.  LMAO!!!!   

That bodyshop is being closed 

Don't forget to cut or drill air release holes and seal all exposed edges as well. 


Air Relaese Holes 

It helps to dry it out and prevent mold........

2sav

just to elaborate a little more....

put 3-4 large (1") holes in the seat base.....helps water escape rather then trapping it in the foam under the vinyl cover....so your boat dont stink like a bum come next season. 

10 4.  Thanks

I was just looking through my restoration pics, but cant find the  process/progress of how I did it, but I do have some with it done before upholstery, I will explain and maybe it'll help a little
1st I laid the base out made some cleats that spanned from the stringers to the gunnels(with storage under seats in mind), they were trapazoid looking pieces, then I laid a flat base down laid out the way I wanted the seats to be ( I made the mistake of not allowing enough space for "big" people so no fat chicks get to sit up front  , I had a bunch of really lightweight mohogany that was left over from a job so I made the framework out of that probably 150 1 x 2 pieces, glued and screwed it all together then I applied the skins, If you go to a hardwood store not home depot, but a place that sells just moldings and hardwood, they will have some flexible plywood. it will bend to really tight radiuses, its mostly used for laying up radius framework. it comes in 1/4 or 3/8 I believe and it is 2'x 8' sheets, I then glued the flexible ply to the framework and fastened it with staples (not the cheezy little ones but the ones my pnumatic nail guns use). once I did that I sanded it all out eased all the edges, cut my access holes for storage, cut the removable seat bases then used the fiberglass resin to coat all the exposed wood surfaces, then off to the upholstery guy. I didn't see where you lived but a guy in Santa Paula did my upholstery for under a grand. And YES make sure you use marine ply, I used 1/2 inch because the seat area actually gets two layers 1" total, one layer for the cushion and a layer for the base. all in all each section Right and left sides weighed around 35 pounds a piece, A little heavier than I wanted but strong as hell.
I hope this helps

They didn't come out as nice in the front as I would have liked, I wanted them to be a little wider it was lose all the floor space or go with a narrower seat I opted for the narrower seats, they are comfortable, and there is room to get geared up now and the girls love the back area  compared to what it was.
If/when I make more, I will  make the base overhang the stringers a couple inches (in the front anyway) rather than have them flush. Other than that they came out nice

that would have required a compound angle, I tried it at first and it seemed to forced you off the seat, if your going to do it that way I would have the upholstery guy build up the lower area with foam rather than frame it that way, the striaght up and down "locks"  you in and really is alot more comfortable than it looks, and better than sliding off the cushion because of the backrest angle. It might be different with foam in it but it felt funky with the angle.
But thats only my opinion.

that would have required a compound angle, I tried it at first and it seemed to forced you off the seat, if your going to do it that way I would have the upholstery guy build up the lower area with foam rather than frame it that way, the striaght up and down "locks"  you in and really is alot more comfortable than it looks, and better than sliding off the cushion because of the backrest angle. It might be different with foam in it but it felt funky with the angle.
But thats only my opinion.

X2 

I used 1/4 in. plactis for the front seats. Heat gun them and clamp/screw them in. I also used rejected oil based paint fro Home depot to paint the wood with. I just did the fronts so far. Wow what a wrestling match!! I used the soft plastic for the seat baks so they "wood" not try to go staight and pull out of the bases.
Sweet work Dozzer!!!  Im humbled!!!

Damn , looking at this interior really makes me want to put full interior back in the Bahner, But $$$$$
buckets are cheap and easy

How many times can i change my mind with this boat

Sorry for the thread jack

2sav

Thanks for the compliment, but I own a  cabinet shop full of wood working tools a small mill actually, and If I built those for a customer, I would have been re-doing them. They are plenty strong, but for a finish carpenter they look like shit........ .........but I guess thats what the upholstery is for 
 The good part is I learned a bunch, and the next ones will be right on.