What type of wood for floor?

Wil,
Roger "nailed" it as far as telling what the ply bond is without the APA ID.

I used 5/8 BCX ply for my 64 and my old 68 cuda.
A little less cost than AC.

Glass and epoxy over 2lb foam makes a solid, lightweight floor.

And yes, I know the arguments. Consider this though; that nasty foam is the first thing we see when the old floor comes up and that's where much of the water is as well. No wonder it gets a bad rap.

I used fir ply(1/2 & 3/4) drenched in CPES for the secondary stringer system and the bulkheads(all vertical, mostly I copied what CC did). I spent some extra time fitting the pieces after a lot of time prepping the hull so I'd have something to fit to, and did the peanut butter and wonder bread thing carefully. Also, I used the pour method so I had to sand the uneven surface to make the floor flat. The sanded(open cell) surface took a fair portion of epoxy before I started laying glass.

The compartments held water before they were foamed.

Carry on OP. Im done. In the middle of a TKO 6 speed upgrade on my Vette. By the way pete it has an inferior aftermarket trans going in. Shame on me.lol oops sorry ill shut up now....

Pete.

Number one the apa mark is buried under layers of glass and carpet now and it doesnt matter because I have to prove nothing to you.

Number two. I have GPSed 54.0/54.5 so if that ole gray will keep up good for you.
Number three I have no reason to insult your boat even though you opened your mouth hinting that mine was slow.
number four. I dont know of any cabinet maker using exterior ply. Im sure he would be using cabinet grade ply.
number five. I dont care about the weight even if you care to arque with me that its more. I weighed the boat against what it should of and it was a little less than spec. And the hijack is you referring that my build was inferior because I didnt use what pete said to. The OP wanted opinions and what folks here had used and my two cents was delivered.I think the OP wants info not arguements hence hijack

8122pbrainard wrote: Wil, Go with Tim's recommendation. I agree with him however I question you using polyester resin and not epoxy. Regarding Vic's cabinet grade ply, yes, it's way overkill and the extra weigh is why his boat is so slow!! BTW, at least he CPES'd and epoxy /clothed it since cabinet grades are typically not bonded with waterproof glues. They are made for interior use.

Pete. To correct you the ply I used indeed does have the marine glue and doesnt have the voids in the plys that exterior grade has. No voids equals less chance of water intrusion. And as for as slow......well if you want to keep up with me Ill gladly throw you a rope, as thats the only way your atom bomb or your all original tique will do it. Lol

Also on a side note last I checked most cabinets have sinks mounted to them so even though its interior its still subjected to moisture. And as far as weight, my boat actually lost a pound or two. No foam remember....I dont remember the axact weight the tique is supposed to be but weighing it I do remember it was a few pounds shy of specifications. Any way I put my two cents in, no need to hijak his thread.

Wil,
Go with Tim's recommendation. I agree with him however I question you using polyester resin and not epoxy.

Regarding Vic's cabinet grade ply, yes, it's way overkill and the extra weigh is why his boat is so slow!! BTW, at least he CPES'd and epoxy /clothed it since cabinet grades are typically not bonded with waterproof glues. They are made for interior use.

Exterior grade ply is just fine. 3/4" is overkill... 5/8" should be more than thick enough. 1/2" may even be fine depending on how you support it. I'd put a layer of cloth on the underside, and a layer of cloth + mat on the top.