1/2 " ply for floor???

[BillP]

Re: 1/2

Re: 1/2

Hmm... I see what you're saying, but...

20' boat x 4' width of ply per sheet = 5 sheets? 5 sheets x 25lbs/sheet = 125lbs extra weight. Is that one more inch of imersion? What's the PPI? Does draft matter? Is it going to effect the COG and make the boat a little squirly at top speed? It's surely equivilent to another person. How much are you paying for your fuel? If the original floor was 1/2", why beef it up? I've seen guys complain about an extra 20lbs between 2-stroke and 4-stroke motors, this is 75-125lbs. difference for a floor. Add epoxy and glass over the entire surface and you've just added another 25-30 lbs.

To each their own...I was merely posting in response to the original question. If the original 1/2" ply floor flexed I would add weight in the form of more wood to make it stop flexing. Thicker ply is easier to install than support structure.

Regardless, most 20' I/Os won't notice a hint of an additional 125lbs unless it's hung on the transom or balanced wrong in the hull...but it If a person wants to use 3/4" and get picky, they can eliminate some of the support structure that 1/2" needs and take some weight off there. 3/4" is way more stiff and needs a LOT less support structure than 1/2". Whatever glass covering is used will be the same weight for 1/2" or 3/4" so that's a wash.

I

 

[Purduebarry]

Re: 1/2

Re: 1/2

AB Marine ply, birch and less voids than PT, 1/2" and Epoxy not poly, 4 lb foam. My two cents. US composite, just as good and cheaper.