Aluminum boat flotation foam?

Question

i have a 13 foot jogn boat.i added a plywood deck and trolling motor on the front of the boat.now the front of course is further down in the water than the back making it harder on the trolling motor and waves coming over the front.would filling in under the wood deck i made with foam are something make the front higher up and not so far in the water.ive added weight to the back aready.front is still to far down in the water.if foam would work filling the void under the deck whats a inexpensive product are way to do it?

Answer 1

Look at the capacity plate on your boat.  this is the rating that the us coast guard has decided is safe to put on your boat that displaces x amount of water.  Adding a deck, foam or anything else is just weighing you down.  if you want a boat with a deck buy a bigger boat. a thirteen footer is probably about 2 persons or 350 lbs total capacity.

Answer 2

If a boat weighs 300 pounds and you put 5 lbs of something in it, how much would the boat weigh?  Is that more than when you started, or less?   Would the boat float higher in the water, or lower?  (Answers:  305 lbs, the boat would weigh more, and float lower in the water.)  

Which weighs more, 5 lbs of styrofoam, or 5lbs of lead?   (Answer:  they weigh the same.)

But put the foam in anyway, it might keep you from sinking, and losing everything, when the boat fills with water (which it will).  How will it accomplish this?  Because, although foam weighs more than air (which the boat is full of now), it weighs less than water (which the boat will be full of soon).

you need to jettison some weight.  And next time, go here:

http://forums.iboats.com and find out how to do it right.

Answer 3

Adding foam will only make the boat heavier. It would add flotation IF you began to sink and took on water.

Answer 4

The foam doesn't take effect until the boat is full of water and going down. It adds nothing to the displacement of the boat. To bring the bow up the only option is to lighten the load up front.

Answer 5

Foam will not help, sounds  like you have created an unsafe condition by adding too much weight to the boat.  I would  suggest that you remove the modifications and eliminate the out of balance condition you created by adding the extra weight.

Answer 6

how big is this trolling motor?  is the bettery up there also   move the battery to the back   your not going to raise the front by lowering the back     foam is a good thing  i dont think it would raise it but it wont hurt it  take anything heavy up front and move it to the back

Answer 7

Derrik,

You have made the front too heavy. I suggest that you get some block styrofoam, the white stuff, and put it under the deck in front. It will support some weight, so you can remove braces and timbers under the deck to lighten it, and support it on the styrofoam. The weight of a trolling motor and 1/2" plywood should not weigh down the front.

Regards,

Dan

Answer 8

especially a boat with a jon boat design, I would mount the trolling motor to the back of the boat and back troll fish.  Due to the design, you really can't put much weight in this kind of boat and foam will only help when it starts to sink.  See if you can get rid of this boat and get a cheap deep V hull aluminum boat about 16 feet.  Best of luck.