Inner tubes instead of floatation foam for my Starcraft SS ?

[jigngrub]

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

I might go do this after the new transom, stringers, floor and floatation are in but before all the wiring, jet intake and pump, and motor are installed. Just to see if it floats and then can calculate how much more it will sink with the extra weight of those things missing.

What's the matter, don't you have any faith in your calculations and installation?

Check it after everything is installed! If the boat starts taking on too much water you can always "CHICKEN OUT and abort the test by putting the plug back in and turning on the bilge pump... but test it on a nice hot day in shallow water.

 

[jigngrub]

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

I don't know what you're asking for. By bilge...are you referring to the entire area below the deck(from bow to stern)?

If so, I don't know how to do any measuring since the floor is in the boat.

How are you going to put the inner tubes or foam in if the deck is already in?

If you decide to do some thing and take the decking up you can measure the depth of the bilge then.

 

[BonairII]

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

Once I decide on what to use for floatation, I'll remove the floor.

 

[jasoutside]

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

Sorry, my boat won't sink!

So you aren't gonna do it huh? Sounds like...

screeching and wing flapping with lame-o excuses

Bonair: You are in need of displacement and drainage man, simple as that. Lot's of ways to do it. Even combinations of methods. Good on ya for thinking outside the box! Though, the tubes would seem to be a real pain to fit and leaky over time. Just a guess mind you.

Now, expanding foam is awesome but there's no drainage unless you provide for it somehow. We've seen what happens with expanding foam over time that will not drain.

That's where the alternative methods come into play, and you've pretty much seen all those: noodles, balls, foam board, jugs, small furry woodland creatures...

I will say on my Sea Nymph project I tried a bunch of "foam core" building. I'm really happy with how that turned out and it added in a bunch of extra displacement.

Question: (maybe I missed it, sorry) Are you going to take your deck up or try and leave it in place? If it's the latter, expanding foam is your choice, eh. [EDIT - Answered...]

 

[BonairII]

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

What do you mean by "adding extra displacement"?

 

[jasoutside]

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

What do you mean by "adding extra displacement"?

That "normally" otherwise would not have been there.

Take a look at how I built the deck and bow structure in the Sea Nymph and you'll see what I mean.

 

[jigngrub]

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

So you aren't gonna do it huh? Sounds like...

Ok, I'm going to do it just for you Jas. It's been a while since I've forgot to put the bilge plug in before launching and then fished all day with the plug out because water never even comes up through the deck drain and it probably needs checking again just to make sure nothing has changed.

I'll make a vid of it.

 

[64osby]

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

I know we are pretty much past the tubes, but I just keep thinking of these sticking up through the deck a set intervals.

As part of boat prep you get out the tire pump and fill up.

 

[jasoutside]

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

Just for the record, I don't think you should do it. I think it's kindof a dum thing to do all around. I know your boat will float and so do you.

But it's clear you insist on the practice, so, I suppose you need to hold yourself to the same standard you expect from others.

 

[BonairII]

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

Just for the record, I don't think you should do it. I think it's kindof a dum thing to do all around. I know your boat will float and so do you.

But it's clear you insist on the practice, so, I suppose you need to hold yourself to the same standard you expect from others.

What am I missing here? I haven't been on iboats much in the last few months. Is there something odd with jigngrubs boat?

 

[73Chrysler105]

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

What's the matter, don't you have any faith in your calculations and installation?

Check it after everything is installed! If the boat starts taking on too much water you can always "CHICKEN OUT and abort the test by putting the plug back in and turning on the bilge pump... but test it on a nice hot day in shallow water.

Jig you dared someone to do it. In order to properly test you need to flood the boat. One the easiest way to do that is with a huge hole in the transom for one. I do not want to flood my new motor with water. The hull should be waterproof if I did my job right and should allow the hull to float above the water level but with the motor should float with the gunnels at or just below water level. The standard is for the boat to be able to float with the gunnels near the surface of the water. I trust my calculations I just see it unnecessary to waste perfectly good motor, wiring and other accessories in a test such as this. With a test as I proposed it will float and show it works without destroying anything in the test. now if I had a boat and motor that could be used as a test that I didn't have any money into and didn't care to not ruin by all means lets try to sink the thing. Or are you funding my boat motor rebuild? I didn't think so. You put out a challenge I will answer it but not at my expense.

 

[jigngrub]

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

Just for the record, I don't think you should do it. I think it's kindof a dum thing to do all around. I know your boat will float and so do you.

But it's clear you insist on the practice, so, I suppose you need to hold yourself to the same standard you expect from others.

No Fear Bubba!

Like I said, it's about time to check it anyway... I will wait 'til warmer weather and do the test in shallow water just for safety concerns.

It might make an interesting thread and it'll let people see that if you take care of your boat the expanding urethane foam won't saturate and will last a very long time.

 

[Ned L]

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

I don't have time to get into it right now, but it looks like there are some real errors with what is here http://forums.iboats.com/boat-restor...-574287-8.html
Also, the USCG requirements for floatation are quite differnet from a simple "how much floatation is needed to keep the boat from sinking".

 

[GA_Boater]

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

What am I missing here? I haven't been on iboats much in the last few months. Is there something odd with jigngrubs boat?

It's not the boat, Bonair. Meant in jest, Jig.

JnG has strong feelings about flotation and at times there have been some lively discussions. Jig advocates the use of expanding foam and basically others say to use whatever keeps a boat above water. Who's right, who's wrong - It doesn't really matter. We will recommend methods that work. Money sometimes comes into play and oddball ideas surface. Like inner tubes, but if you don't ask then you will never know.

 

[jasoutside]

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

I don't have time to get into it right now, but it looks like there are some real errors with what is here http://forums.iboats.com/boat-restor...-574287-8.html

OK, so, how bout just a hint then?

 

[jigngrub]

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

What am I missing here? I haven't been on iboats much in the last few months. Is there something odd with jigngrubs boat?

Nothing odd at all, my boat has excellent floatation and bilge drainage and floats like the Lund in the video I posted in post #2 of this thread. Click on the link and watch the complete video.

Jig you dared someone to do it. In order to properly test you need to flood the boat. One the easiest way to do that is with a huge hole in the transom for one. I do not want to flood my new motor with water. The hull should be waterproof if I did my job right and should allow the hull to float above the water level but with the motor should float with the gunnels at or just below water level. The standard is for the boat to be able to float with the gunnels near the surface of the water. I trust my calculations I just see it unnecessary to waste perfectly good motor, wiring and other accessories in a test such as this. With a test as I proposed it will float and show it works without destroying anything in the test. now if I had a boat and motor that could be used as a test that I didn't have any money into and didn't care to not ruin by all means lets try to sink the thing. Or are you funding my boat motor rebuild? I didn't think so. You put out a challenge I will answer it but not at my expense.

So you don't think a boat will sink by just leaving the bilge plug out? Look at this thread:
http://forums.iboats.com/stupid-hum.../sold-my-old-boat-now-its-bit-wet-584575.html
... and then leave the plug out on your boat when you've finished it to see if it'll sink with just the bilge plug out.

Floating with the gunwales just above the water may be your standard and maybe a way outdated standard for boats, but my standards are higher... much higher. In case you didn't watch the vid:

Lund Boat Floatation Video - YouTube

... and these:
Unsinkable Key West Boat - YouTube

Halve Whaler rondje - YouTube

Key West Boats Inc. - Your Key to Performance and Quality

... and how about an unsinkable and self-righting 43 footer?:
Coast Guard Response Boat Self-Righting Test - YouTube

The standard of the gunwales floating even with or a few inches above the water is substandard IMO.

 

[Ned L]

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

Question from Bonair: "I'm guessing my boat, motor etc weighs in the neighborhood of 1200 lbs (16' SS w/ 70hp).....how many sheets of pink foam board would I need? "

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OK, for the point of discussion, IF we were to say the whole boat and outboard are aluminum (but we know they aren?t, there is some wood, upolstry, plastic, etc in the boat, and some steel & plastic in the outboard). For now we'll call it all aluminum as it is probably 90%+ aluminum. Aluminum has a specific gravity of 2.5 ? 2.8 (That means that one cubic foot of aluminum weighs 2.5 to 2.8 times that of a one cubic foot block of water.)
If your rig weighs 1200LBS and we were to say that the specific gravity of your boat is 3.0 (we?ll call it a bit denser than straight aluminum to account for some of the steel in the O.B. and other stuff that is denser than aluminum). The specific gravity of water is (1), and water weighs 64 pounds /cu.ft., so your boat at a specific gravity of 3 is 192lbs /cu ft (3x64 lb/cu.ft =192 lb /cu.ft). At 192 lbs /cu.ft your boat has a solid volume of 6.25 cu ft (1200lbs ? 192 lbs/cu.ft = 6.26 cu.ft). 1200 lbs of water is 18.75 cu ft of volume (1200lbs ? 64lbs/cu.ft = 18.75 cu.ft). Your boat displaces 6.25 cu.ft, and you need to diplace 18.75 cu.ft to just stay even. So, ? 18.75cu.ft ? (minus) the 6.25 you are already displacing means you need to add an additional 12.5 cu.ft of volume (floatation). This would be about 2? x 2? x 3.25?in total volume.
Now keep in mind that this was a theoretical exercise based on calling your rig probably 90%+ aluminum and that this would be roughly the amount needed to just keep the gunwale at the surface of the water and nothing extra to float the gear OR the people in the boat.


It is not nearly as simple as this for a 'glass boat.

 

[Ned L]

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

...

 

[kahuna123]

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

Wow, just wow. Winter must really suck

 

[jigngrub]

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

Question from Bonair: "I'm guessing my boat, motor etc weighs in the neighborhood of 1200 lbs (16' SS w/ 70hp).....how many sheets of pink foam board would I need? "

-------------------------------------------------------------------------------------------------------------------------
OK, for the point of discussion, IF we were to say the whole boat and outboard are aluminum (but we know they aren’t, there is some wood, upolstry, plastic, etc in the boat, and some steel & plastic in the outboard). For now we'll call it all aluminum as it is probably 90%+ aluminum. Aluminum has a specific gravity of 2.5 – 2.8 (That means that one cubic foot of aluminum weighs 2.5 to 2.8 times that of a one cubic foot block of water.)
If your rig weighs 1200LBS and we were to say that the specific gravity of your boat is 3.0 (we’ll call it a bit denser than straight aluminum to account for some of the steel in the O.B. and other stuff that is denser than aluminum). The specific gravity of water is (1), and water weighs 64 pounds /cu.ft., so your boat at a specific gravity of 3 is 192lbs /cu ft (3x64 lb/cu.ft =192 lb /cu.ft). At 192 lbs /cu.ft your boat has a solid volume of 6.25 cu ft (1200lbs ? 192 lbs/cu.ft = 6.26 cu.ft). 1200 lbs of water is 18.75 cu ft of volume (1200lbs ? 64lbs/cu.ft = 18.75 cu.ft). Your boat displaces 6.25 cu.ft, and you need to diplace 18.75 cu.ft to just stay even. So, … 18.75cu.ft – (minus) the 6.25 you are already displacing means you need to add an additional 12.5 cu.ft of volume (floatation). This would be about 2’ x 2’ x 3.25’in total volume.
Now keep in mind that this was a theoretical exercise based on calling your rig probably 90%+ aluminum and that this would be roughly the amount needed to just keep the gunwale at the surface of the water and nothing extra to float the gear OR the people in the boat.


It is not nearly as simple as this for a 'glass boat.

Just guessing I'd say BA's bilge displaces 12-16 cubic feet which is pretty typical for a tinny displacement and is plenty enough room for the correct amount of floatation... if not more.

... and, 1 4'x8' sheet of 2" thick foam is 5.44 cubic feet. Add in a waste factor for cutting the foam to fit and BA could probably fill his bilge with 4 sheets.

http://www.homedepot.com/h_d1/N-5yc...53&langId=-1&keyword=sheet+foam&storeId=10051

Yeah, that's $138 for sheet foam floatation... and if BA's boat is worth less than $100 it probably isn't worth putting foam in it.

How much would you say your boat is worth BA?