foam info

weekender1

Petty Officer 3rd Class
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Apr 12, 2011
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99
is there a way to figure out how much foam you would need for a tri hull?? i know that i have to do 10 long by 5" deep at the stringer side that then sloops up to 1" ?? i am looking at useing the 2lb foam??
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
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12,932
Re: foam info

gallon of each.


when you pour.....dont just dump all in one spot......spread the pour around and leave it.... once the bubbles start to form....you cant disturb them or the foam wont activate
 

archbuilder

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Sep 12, 2009
Messages
5,697
Re: foam info

You might try calling areomarine products, the owner is really good about helping answering questions. Just google them.....they also have some pretty good prices. The warmer it is, the further it will go by the way.
 

jigngrub

Fleet Admiral
Joined
Mar 19, 2011
Messages
8,155
Re: foam info

Give me the length, width, and depth of your pour and I'll figure it for you... a pic of what you're pouring would help too.
 

Yacht Dr.

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Feb 26, 2005
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5,581
Re: foam info

is there a way to figure out how much foam you would need for a tri hull?? i know that i have to do 10 long by 5" deep at the stringer side that then sloops up to 1" ?? i am looking at useing the 2lb foam??

Boat .. pics .. please ..

Are you saying you have One stringer ? . .. more info please before we start suggesting.

How do you plan the deck .. are you glassing it ?? bagging your foam ??

Just Not enough Information IMO ..

Its not how much..its how its applied..

Again.. pics please ..

YD.
 

weekender1

Petty Officer 3rd Class
Joined
Apr 12, 2011
Messages
99
Re: foam info

i am going to glass in the deck once i figure oiut if i want to put the deck on top of the old glass sides or under? but the langth is 10 the depth is 5" to 1" deep and width is 8"in the one picture i finaly got all the old foam out of the boat and the other picture shows the side where i am trying to figure out to put new deck under or on top of the space i left.. 2011-07-31 16.51.27.jpg2011-07-31 14.53.45.jpg
 

jigngrub

Fleet Admiral
Joined
Mar 19, 2011
Messages
8,155
Re: foam info

10'x5-1"x8"= 1.675 cubic feet and it looks like you have 2 voids, one on each side so double the 1.675= 3.35 cubic feet... so 2 4lb. kits should get you by with a 20% waste factor.
 

Yacht Dr.

Vice Admiral
Joined
Feb 26, 2005
Messages
5,581
Re: foam info

My calcs come closer to 5 cubic feet .. but does not matter.

5 cubic feet of 2 lb foam will give you about 300 lbs of floatation ..

Is the foam structural ? because its not for floatation.

Do you even need foam ?

Just wondering out loud here ....

YD. :)
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: foam info

the only problem with the pour foam...is the huge waste...when you pour....you pour on the high side and let it run down to the center or low side......

then it pools and your one inch thick foam has expanded 15 inches tall.

so go wayyy over on the calcs if you dont have a supplier in town......nothing worse of being caught short of supplies and having the project halted 10 days waiting for a half leiter of foam !

oh.....by the way........wear a set of good paper coveralls or tyvec....and make sure you have lots of disposable gloves handy....you will go thru 10 sets.

if you get this stuff on your clothes or skin.....it does not come off !
 

weekender1

Petty Officer 3rd Class
Joined
Apr 12, 2011
Messages
99
Re: foam info

well i am thinking about putting in the flooring before i do the foam hopeing that will work and was thinking about 3 or 4bl for the sides from stringer to hull then maybe 2bl for the kell or center..
 

weekender1

Petty Officer 3rd Class
Joined
Apr 12, 2011
Messages
99
Re: foam info

i have noticed in a couple of places in the hull where the hump is for the try hull seems soft? is to put all your weight on that spot you can hear sounds of like eating chips but when i have some one else stand there and look i see it move but no cracks in the gell?? but as for structural might be i am raising the flooring up maybe 1/2 inch to 1" inch.. the one thing im stuck on is can't do my stringers yet till i get the engine mount made the old on for the 4cyl was a 2"x6" and since im putting in the inline 6 i am thinking of useing a 4"x6".. to bad we on iboats don't have a place where if some one has extra stuff like resin and such would want to sell to other iboaters on here.. i still need the engine allinment tool when i get there.. if we ever did add a spot like that to sell to other iboaters put me on the Looking List lol..
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: foam info

seemingly weak lay up areas in a hull are common during the build phase.

by the time you get your stringers in there....then tab them into the hull then add the foam.....they will be solid.
if you are very unsure.....you can add a layer or 2 of 1.5 oz csm....just grind off the top layer of contaminated old resin....more like scuff it. and glass over it.
but watch out......you will be adding weight.
some people do a full wrap of 1708 this is very strong.....but heavy....

as far as the motor cage.....make sure your measurements are good with the inline 6...the mounts are different. the six is longer so you will have to move the forward mount.
(keep in mind....you will also have to change the dog house)

you can go 4x6 on the mounts.....some early builders just layed a few pieces of plywood on the flat till they had reached the desired height.
the best bet...is the rule of thumb....find what was there and duplicate it...just make it better.

as far as the alignment tool.....you could rent one from a local mechanic for a good deposit.
 

Sleeper-6

Petty Officer 2nd Class
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Oct 7, 2010
Messages
114
Re: foam info

I have fount that when pouring foam into open cavities it was less wasteful to pour a little at a time and see how it expands. on the next pour I would fill in the low spots, and so on. Once it hardens, trim off the excess and toss it into the next cavity and start the pour process again. A regular hand saw for wood saw works great to trim foam. It takes a bit longer, but the waste is minimized.
 
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weekender1

Petty Officer 3rd Class
Joined
Apr 12, 2011
Messages
99
Re: foam info

I don't think its structural if I remember right when I pulled the old flooring off the foam was not on the bottom side . I am also thinking about putting the new floor about 1/2 to 1 inch higher and place it on top of the 2 inch glass lip.I left so I'm hoping this will be good I'm going to use 1/2 board for the new floor. any ideas?? Also with it being a tri-hull think it would be best to foam then do flooring?
 
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