Thanks! This is SIMPLY AWESOME! (Can I build a liveaboard with this pink stuff? LOL!)



I - BUOYANCY CALCULATION - using your numbers



I kind of figured out the buoyancy that you reported above.

You stated that as is, TOTAL = 460 lbs.

And each Pink board is 1 inch x 17 in x 96 = 62 lbs

So by default the 50% thicker white panel would be 50% more buoyant at 93 lbs, but you cut this even further to 14 inches, since the 2 x 2 (which are actually 1.5 x 1.5 inches) take up the remainder of the 3 inches (top and bottom) to make it up to 17 inches. So, for the displacement argument and calculation, we will leave it in as if the WHITE panel is 17 inches, it will not really make a difference since the wood would also float (no?).



As per 1 inch x 17 inches x 96 inches dimensions and the specs stated above, I get the following buoyancy numbers:

a) PINK (rounded slightly up) = 62 lbs ea x 4 (2 per side) = 248 lbs

b) WHITE (again, rounded up) = 93 lbs ea x 2 (1 per side) = 186 lbs

Then you have:

c) PINK inner boards 1 x 12 in x 96 inches = 44 lbs ea x 2 (1 per side) = 88 lbs



I get a total of 522 lbs of buoyancy vs your 460 lbs. Granted, the 2 inner PINK pieces are sitting higher in the pontoon and flush with the top AWAY from the water, so their buoyancy could be diminished by the fact that they may not even BE inside the water. You claim that you don't want it to be more than 60% submerged so that means if we adjust for that, meaning that only 5.2 inches of those particular's boards' 12 inches will be submerged or 43% of the total buoyancy that the board can provide will be used, then it cuts it down by about 50 lbs so 472 lbs of buoyancy! Very close to your stated 460 lbs. Then again, I am not discounting the diagonal cut in the front, so that may as well be the one factor that would match it to your number.



II - ADDITIONAL BUOYANCY -



Let's go crazy and add more buoyancy (and cost), overdoing it for the sake of EXTRA Safety:

a) 2 inch thick PINK Boards - so you have to buy 2 boards of 2 in x 48 in x 96 in)

b) 3 inches thick WHITE Boards - need to buy only 1 board of 3 in x 48 in x 96 in Styrofoam

And instead of a pontoon lateral size of 17 in x 96 in, lets make it 24 in x 96 in

Total thickness of Pontoon = 7 inches

You may have to add more side to side reinforcement / attachment points for platform-pontoon connections. The platform would cover most of the top portion of the cat, giving more Real Estate to put stuff and people.



How much is the buoyancy? How about 1,332 lbs?

So why would you want this? Well if you load the damn thing with:

1) A couple of guys - 200 lbs a piece = 400 lbs

2) All their camping gear - 50 lbs a piece = 100 lbs

3) A small/med cooler with ice = 50 lbs

4) A 35 lb trolling motor and a 50 lbs AGM battery in its case = 85 lbs

5) Plus the hardware/deck/sail/mast (aprox) = 60 lbs



You would be close to the 52% of the total buoyancy, still under the stated 60% for it to work properly and it will be about 4 inches higher from the water than the original design since it is a taller pontoon, therefore dryer. This may be OVERKILL to some, and a performance deterrent for speed, but an ACID TEST like this one is a great exercise. True, it may be slow as a snail but it should not feel cumbersome as if it had a lot less buoyancy.



I've been reading on the White Styrofoam and it turns out it may not be a good idea as it soaks up a lot of water.....Maybe using more of the PINK XPS board?



Note: Make sure YOU DO NOT USE EPS Board or even Polyiso.....Only use XPS which absorbs very little water. Maybe use some gel to seal it around?



Thanks and sorry for my long tirade!