Inner tubes instead of floatation foam for my Starcraft SS ?

[Woodonglass]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

JMHO, but the OP has stated that he's going to use the Pink Slab foam. He has NOT posted anything since Feb 13th. I think we should see if he posts other issues and respond to those. I think this deserves one of these...

 

[BonairII]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Yup....after realizing(remembering) how little room there actually is under my floor....the "sealed air" thing def isn't feasible.

I'm going to cram pink foam board(and noodles that I already have) under the floor. I'm also going to stuff as much pink board/foam as I can under the gunwales, splash well, and under my casting deck.

Going to start DE-constructing my boat later this week, so I can get the floatation stuff done....and redesign my casting deck.

 

[jigngrub]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

JMHO, but the OP has stated that he's going to use the Pink Slab foam. He has NOT posted anything since Feb 13th. I think we should see if he posts other issues and respond to those. I think this deserves one of these...

Meh, at least this is a current topic and red banners aren't being ignored and years old topics being dredged up.

Going to start DE-constructing my boat later this week, so I can get the floatation stuff done....and redesign my casting deck.

Are you going to have to tear up carpeting to take your boat back apart?

 

[BigFishDave]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Meh, at least this is a current topic and red banners aren't being ignored and years old topics being dredged up.



Are you going to have to tear up carpeting to take your boat back apart?

Hi All:

I'm the guy that put in the pink foam. Still working on it a little every day after work. It comes in sheets 4' x 8', and has the pink panther symbol on it. I got the 3" thick sheets. They were a little over $50 each.

So far I got 2 1/2 sheets installed, by cutting it up with a utility knife and stuffing it everywhere I could. Each sheet lifts 500 lbs, so I have added about 1,250 of lift, so far.

I still needed another 1,000 lbs of lift, but could not fit anymore. I got the additional lift by buying two of these, which I will tie off to the cleats on the sides of my boat: Prostock Marine

Each fender lifts 500 pounds. They have all sizes.

Yes, they are spendy; but I tried to price out fabricating something from large diameter pipe, and the cost was too excessive. The fenders have triple use: fender, additional boat flotation, emergency life raft.

 

[BigFishDave]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Hi All:

I'm the guy that put in the pink foam. Still working on it a little every day after work. It comes in sheets 4' x 8', and has the pink panther symbol on it. I got the 3" thick sheets. They were a little over $50 each.

So far I got 2 1/2 sheets installed, by cutting it up with a utility knife and stuffing it everywhere I could. Each sheet lifts 500 lbs, so I have added about 1,250 of lift, so far.

I still needed another 1,000 lbs of lift, but could not fit anymore. I got the additional lift by buying two of these, which I will tie off to the cleats on the sides of my boat: Prostock Marine

Each fender lifts 500 pounds. They have all sizes.

Yes, they are spendy; but I tried to price out fabricating something from large diameter pipe, and the cost was too excessive. The fenders have triple use: fender, additional boat flotation, emergency life raft.

I should add this: I have used the pink foam on another boat, and put it in about 10 years ago. I pulled up the floor to install a cable, and the foam still looked new (and dry), after repeated submersion when washing out the boat. It is good stuff.

 

[BonairII]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

$300+ for inflatable fenders??? Yikes!

 

[jbcurt00]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

$300+ for inflatable fenders??? Yikes!

Agreed....

Wouldn't it be cheaper to just keep one of these handy? :faint2: :laugh:

 

[GA_Boater]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Cheapest yet is a St. Christopher medal around your neck.

 

[phillnjack2]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Well its seems that all these people who are knocking the tube idea have never heard of inflatable bouyancy.

the foam is a terrible idea,its the cheapest way of manufactures making cheap boats seem strong.
i have a boat with foam floatation and its crap, it isnt anywhere near as good as air pockets by polastic containers
definitely 100% less bouyancy than inner tubes, and people dont realise that the foam takes on water and holds it there.
all this about a boat not sinking with foam is total rubbish, i can prove it.
i would love to be at a show wherethe boston whaler is cut in half etc etc etc, i would then cut into the sealed edges they
have sprayed and then let people seethe foam soak up the water.
My boat was around 500 pounds too heavy untill i got the foam out and dryed it in the sun then had to squeeze water from it.
there is no such thing as fully closed cell foam in any of the boats,its a big myth spread by fools and has become a legend
that should not be taken too seriously.
Thousands of boats are out there that weight atleast twice what they are meant to due to the foam being a big wet soggy sponge.
the idea of innertubes is far superior in every way. if water gets under the deck you can simply drain it away, you cant do that with foam
you will also get a lot more bouyancy from the tubes per cubic foot than with foam. the only time the foam is good is if it dont get wet.
as long as you dont get a puncture in all the tubes at the same time youl have plenty of bouyancy.
when people say tubes dont hold much air just look at inflatable boats.
after having waterlogged foam i would go down the route of hundreds of plastic bottles and conatiners, no chance of all of them getting puncture plus you can always get them out if you want, the foam is a pain to get out and just leaves a terrible mess.
also 2 truck tubes will hold up a loat more than you might think,plus if they are compressed it will be even better,just dont pump them up too much or the floor will bow.


phill

 

[jbcurt00]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Interesting perspective Phill.

 

[jigngrub]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Well its seems that all these people who are knocking the tube idea have never heard of inflatable bouyancy.

the foam is a terrible idea,its the cheapest way of manufactures making cheap boats seem strong.
i have a boat with foam floatation and its crap, it isnt anywhere near as good as air pockets by polastic containers
definitely 100% less bouyancy than inner tubes, and people dont realise that the foam takes on water and holds it there.
all this about a boat not sinking with foam is total rubbish, i can prove it.
i would love to be at a show wherethe boston whaler is cut in half etc etc etc, i would then cut into the sealed edges they
have sprayed and then let people seethe foam soak up the water.
My boat was around 500 pounds too heavy untill i got the foam out and dryed it in the sun then had to squeeze water from it.
there is no such thing as fully closed cell foam in any of the boats,its a big myth spread by fools and has become a legend
that should not be taken too seriously.
Thousands of boats are out there that weight atleast twice what they are meant to due to the foam being a big wet soggy sponge.
the idea of innertubes is far superior in every way. if water gets under the deck you can simply drain it away, you cant do that with foam
you will also get a lot more bouyancy from the tubes per cubic foot than with foam. the only time the foam is good is if it dont get wet.
as long as you dont get a puncture in all the tubes at the same time youl have plenty of bouyancy.
when people say tubes dont hold much air just look at inflatable boats.
after having waterlogged foam i would go down the route of hundreds of plastic bottles and conatiners, no chance of all of them getting puncture plus you can always get them out if you want, the foam is a pain to get out and just leaves a terrible mess.
also 2 truck tubes will hold up a loat more than you might think,plus if they are compressed it will be even better,just dont pump them up too much or the floor will bow.
phill

You've just won my share of Savory Ducks... doubled!

Watch this:
Lund Boat Floatation Video - YouTube

 

[BigFishDave]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Interesting perspective Phill.

There are many types of foam. Some does absorb water, like spray foam and some forms of rigid foam, but XPS (extruded polystyrene) is waterproof.

XPS is a waterproof, rigid insulation material. It is made from polystyrene pellets, which are mixed with various chemicals, then heated until the pellets liquefy. When the pellets cool, they turn into tiny beads. Then the beads are heated and injected into flat molds. When the molds cool, the material is cut into panels of various lengths, widths and densities to use as insulation. The final product is rigid, dense and waterproof. As a result, XPS is commonly used for roofing and below grade to insulate cement slabs and foundation walls.

This is what I'm talking about. I mentioned above that I have used this material in another boat and found it to be water proof.

Read more: What Types of Closed Cell Rigid Insulation Are Waterproof? | eHow.com What Types of Closed Cell Rigid Insulation Are Waterproof? | eHow.com

I have also found that the manufacturer of my boat used some spray foam, wich I detest.

Also, I'd like to briefly mention that the fenders I got lay along the outside of the gunwale, not inside the boat. I have found it necessary to use these because I have no more space on the inside of the boat to add XPS.

I appreciate all the comments and input with this difficult problem us boat owners have with flotation. Many boat owners don't care about the safety of keeping a flooded boat afloat, but we apparently do.

BFD

 

[jbcurt00]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

I didn't mean that kind of interesting perspective.

Pink/Blue rigid & probably pour in foam will all find their way into my glass & tin builds alike. And for ease of installation & to provide wire chases, some noodles may find their way into my gunwales.

BigFish, if the inflatable fenders work well for you, that's great. You solved the problem as you saw fit & at a cost/benefit that was acceptable.

As for the rest, to each his own

But if it were mine, I'd NEVER depend on a below deck, inflated bladder of any kind (inner tube or other) to be a good or long term solution.

 

[BonairII]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

If my boat had more room below the decking...is def love to put some rigid air chambers for floatation. The inner tube idea was a decent one, but the fact that they could puncture(esp if deck screws etc punctured them)....makes inner tubes too much of a crap shoot.

Sealed plastic containers, whether they are sealed detergent bottles or something fabricated specifically for floatation....still remain a viable option IMO. If I had another 6-12" of vertical space under my deck, I would seriously consider using laundry detergent bottles(or whatever) for floatation.

The one thing that came out of this thread that has def helped me....is that I now realize that I need to install floatation foam under my gunwales, splash well(in addition to under the deck) to help to boat stay upright in the event of a swamping.

I'm also going the redesign the framework under my casting deck(on the bow) to allow me to stuff some floatation foam under there also. I don't mind giving up a small portion of the storage space for some added buoyancy.

 

[BigFishDave]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

I put a lot of pressure on myself to meet the weight requirement of the boat (motors batteries, gear, for example), when calculating how much flotation I need. I used the one cubic foot of displacement = 64 lbs (of sea water). Fresh water is just a little less, so you need a little more flotation.

Anyway, a life jacket may have only 23 lbs. of bouyancy, yet it can support a person that weighs 200 lbs. This is because the body is made up of mostly water, which weighs the same as the water you find yourself in if you jump overboard. Plus there is fat, and bones.

The point I am getting to is that a boat, is made of multiple materials - each a different density which affects how much flotation is needed. My plywood floors (covered with vinyl) have a different density that the aluminum hull, for example. The glass windshield is really dense, but my foam cushions may float (for a while).

I just weighed my boat on the truck scales and subtracted the trailer.

What I really should do is an estimate of the densities of each of my boat component materials. Then figure if there are negatively or positively buoyant components, and how much of each.

I might be able to subtract the floor because it is made of wood, but I have not. To do it right I would need to know the maximum water absorption % of each material.

 

[BigFishDave]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

What Phil said seems to be correct in that foam, including XPS will absorb some water, and is NOT completely water proof, although the absorption rate of XPS is quite small, and possibly hardly enough to be significant.

I found some technical data on the water absobtion of XPS. The standard 150 and 250 have water absorption capacities of 0.10%. The higher density 400, 600, and 1000 have water absorption capacities of 0.05%.

This seems to mean the stuff (Foamular 150) I bought for a 3"x4'x8' sheet that has buoyancy of 500 lbs, could be reduced by 0.10%; so it would only lift 455 lbs instead. A sheet the same dimensions of Foamular 400, with a buoyancy of 500 lbs, would be reduced by only 2.5 lbs. resulting in a buoyancy of about 497.5 lbs due to higher density. [Note: these figures have been corrected (they are correct now, but not on Feb 26) due to a post by Grandad below].

See the table below - click on it.



I am going to try (in addition to pink foam, and my two high dollar fenders) to add an inner tube on the front deck of my boat. Having done all that, I think I will have made my best effort at finishing up my flotation project, and moving on to electronics. Safety first - boat flotation, personal flotation, a class IV throwable life ring, and then saftey of installed and portable electronic equipment.

I might even take a boating class!

Thanks.

BFD

 

[Grandad]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

This seems to mean the stuff (Foamular 150) I bought for a 3"x4'x8' sheet that has buoyancy of 500 lbs, could be reduced by 0.10%; so it would only lift 450 lbs instead. A sheet the same dimensions of Foamular 400, with a buoyancy of 500 lbs, would be reduced by only 25 lbs. resulting in a buoyancy of about 475 lbs due to higher density.BFD

Just a note for perspective. Your math is suspect. 0.10% of 500 lbs is only 0.5 lbs, not 50 lbs. - Grandad

 

[73Chrysler105]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Just a note for perspective. Your math is suspect. 0.10% of 500 lbs is only 0.5 lbs, not 50 lbs. - Grandad

Grandad is right 50lbs would be 10% not 0.10% which kinda makes the absorption rate a non issue. Especially since there is another factor in that absorption rate which is saturated over time and that is not listed.

 

[BigFishDave]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Grandad is right 50lbs would be 10% not 0.10% which kinda makes the absorption rate a non issue. Especially since there is another factor in that absorption rate which is saturated over time and that is not listed.

Holy cow!! Thanks Grandad. I really appreciate the reply. I was never that good at math.

BigFishDave

PS: I'm going to go back and try to edit that post and make the correction(s) you pointed out.

 

[BigFishDave]

Re: Inner tubes instead of floatation foam for my Starcraft SS ?

Holy cow!! Thanks Grandad. I really appreciate the reply. I was never that good at math.

BigFishDave

PS: I'm going to go back and try to edit that post and make the correction(s) you pointed out.

http://www.uscgboating.org/regulations/boatbuilder_s_handbook/flotation_part1_e.aspx

Table K (scroll down) shows how much each material component of the boat weighs under water:
http://www.uscgboating.org/assets/pdf/downloads/FLOTATION.pdf

So you don't need as much flotation to float the total weight of your boat, since the boat will weigh less when swamped, then it does on the truck scale.

For example, aluminum weighs only .63 or 63% of its weight when submerged. You multiply .63 times the number of pounds of aluminum you have in your boat, to get the corresponding amount of flotation you need to keep that much aluminum afloat.

Fiberglass has a K value of 0.33
Plywood has a K value of - 0.81
Steel is 0.88
Gasoline is - 0.37

These numbers (and others) are in the table K of The Boatbuilders Handbook.


Calculating the Volume of a cylinder