A quiet queery - re: floatation

[Wild Dingo]

Okay after the great washout of May we have finally sorted the insurance mob out and in so doing have been making some re-placement purchases for those things we lost

Queery is:
A lot of these things come surrounded in foam blocks (polystryne?) and I was wondering before I go madly chucking them on the tip would some of this stuff be okay as floatation? In a chamber perhaps? (this is a general question and not specific to any design)

Some are fairly large peices ie: around the fridge washing machine table saw etc and others small blocks largest of these is solid and about a foot square others down to a couple of inches square and rectangle

Anyway not being one to toss out anything if I can find a use for it I wanted to ask before possum chucks a tata and makes me chuck them on the tip... if I have reasoned reason for keepin all this stuff I have an excuse to store it.

Cheers in advance

[ 08-23-2005, 02:17 AM: Message edited by: Wild Dingo ]

[Dan Hobson]

Send it to someone else as packing material for a gift or something like that. As flotation, anywhere you might put it, it will probably not serve very well. But I do suppose that if you were running foam or something of the kind inside a closed floatation box, you could use it as filler, but it sounds like a pretty messy job to do it that way. Packing material is best used as packing material.

[Wild Dingo]

mmm Thanks Dan :cool:

I say mmm simply cause thats an interesting response... and not to argue or debate your reply which is a good one mate... but given that Ive known people to use empty plastic drink bottles for floatation and not as plastic drink bottles for which purpose they were designed and I know of others that have put to use other things to uses for which they were not designed but served equally as well is why I find it interesting...

Why though would it not be any good as floatation? Ive tossed some of this stuff in the bath with Joshy and its floated very well... ive even got some tied to the tree near the creak and it also floats very well 2 weeks and still bobbin around out there... I shoved a small seamingly sealed peice into the washing machine when possum wasnt looking and mate it hasnt changed shape or form at all its not sopping wet and its not damaged and after tossing it into the creek it floated away quite cheerfully... so I wonder at the why of not using it as floatation

Its not like it is loose packing stuff these are blocks and seem to be well contained stuck together if you will...

mmm will have to ponder some more... cheers mate! :cool:

[Wild Dingo]

Okay zapped out to the shed to take a pic or two... so this is the sorta stuff Im talking about

http://www.imagestation.com/picture/sraid183/p740cd2a3ca3164a4cd7b8adb9c66d70d/f2b14757.jpg

These peices are about a foot high by 5 or so inches square... seem to have some sort of binder incorporated into the outside to keep it from crumbling into gadzillion tiny little balls... when I cut one corner of the square only a few small balls separated and I ended up with a small triangle that holds together reasonably well and the square chunk is still good as it was...

Anyway there we go Ive got ****eloads of this stuff and just didnt want to toss it out if I could use it elsewhere... ah well

[skuthorp]

How about beer cans Shane, as in the regatta at Darwin. For wooden boaties read Port casks :cool:

[Dan Hobson]

OK So we're talking about the blocks that are really a gazillion little grains bound together. My thinking is this: If that stuff is on my boat, it's ok for a good number of years all by itself. I've seen it used in docks and other floating artifacts such as life preservers. But with age it will start to disintigrate. The key is a protective coating of one kind or another to make sure the little bits don't come away at some later date and go clog a pump. Stabilization is the word. A cloth bag painted and secured somewhere to the boat because it's not much good to you if it just floats away right?? The fact is, you are right. It can make excellent floatation. But if it's kicking around, it will cast off little crumbs. I was thinking that if one were to be using something like boat foam to fill a compartment, one could use a lot less foam if a block of this were glued to the bottom of the compartment first. That would both stabilize it and protect it. Other considerations in the matrix are will it be exposed to oil or gas if the boat fills up with water?? I don't think I've seen this material used near a tank. Some foam products completely disolve when exposed to gas. It seems these blocks are one quarter of a cubic foot each. So afixed to the hull and the hull holed and filled with water they would each float about 22 pounds. My boat is four tons so I guess I would need about 400 of these things or a hundred cubic feet to achieve neutral bouyancy. I much prefer to think of some kind of inflatable system.

[paladin]

don't dood it Shane...go with the soda bottles...different plastic....with that foam you'll have nuthin' but grief......

[formerlyknownasprince]

Shane

Take one of these blocks out and put a couple of drops of petrol on it. See what happens.

The best flotation - is a well-fastened, well-caulked boat

Ian

[Wild Dingo]

:D no worries mates I'll play it safe!! Explained well Dan and thanks to all cheers! :cool:

[paladin]

OR...as the CLEEKSTER sez...fuggettaboutitt....

[Bruce Hooke]

On my father's sailboat they used white foam as the flotation. It held together reasonably well, but over the years, sitting in the bilges, some if absorbed so much water that it would likely have sunk all on it's own if we had put pieces of it in a bucket of water. So, while I do think there is a place for foam flotation in some boats, I would NOT recommend using cheap foam for the purpose...

[Bruce Hooke]

Originally posted by igatenby:
Shane

Take one of these blocks out and put a couple of drops of petrol on it. See what happens.

The best flotation - is a well-fastened, well-caulked boat

IanThis may well be true on a ballasted sailboat or on a motorboat with a large inboard motor. In both cases the amount of foam required to allow the boat to float if it swamps would be too large to be practical. HOWEVER, it strikes me as downright dangerous to suggest that floatation in small unballasted open boats is unnecessary! Any small, unballasted open boat should at a minimum float reasonably level in the water if it swamps, and it would be MUCH better for it to float high enough to be bailed out. For that to be true most designs will require some form of floation, whether it is foam, ping-pong balls, sealed tanks or one of the many other solutions that have been developed to deal with this problem.

[Ian McColgin]

Well, I wrote a nice long piece about how soda bottles and ping pong balls only give a bit over half the enclosed space in floatation but the machine would not accept the formula format. So compare that yourself. You'll see that the only reason for that approach is a surfeit of free material and an overabundance of space to put it in.

Blocks of packing foam are just dandy for securing under seats, thwarts and decks. Use some openmesh stuff to encase it and staple that under. You may have to cut a few blocks to make nice regular shapes that fit together. A bow saw with a wire instead of a blade will do.

By the time it deteriorates you'll have plenty more.

G'luck.

[JimD]

I used some in a completely sealed, unvented float compartment of a kayak once and after a couple years decided to redeck the kayak so I had the chance to inspect it. It was just just fine but that was only two years. I decided not to leave it in.

[Dan Hobson]

Water weighs 88 pounds per cubic foot. That means 100 cubic feet of displacement will float four tons. Even a heavy boat can find a way to carry enough internal emergency floatation one way or another to stay afloat. So if you figure that fourteen standard 2 litre coke bottles displace one cubic foot, 1450 of them would float four tons (and take up about a hundred and thirty cubic feet of space). I still prefer some sort of internal inflatable system for emergency floatation in the case of catastrophic hull failure. But I do kind of admire that american hippie who built his own private island in Mexico out of plastic bottles inside fish net bags.

We were off the coast of china in the good ship cantalope.
Went down a creek and sprang a leak with a load of ivory soap.
The shore's a thousand miles away, and maybe a trifle more!
We lost all hope and grabbed the soap and washed our selves ashore!

[Gary E]

Originally posted by Dan Hobson:
Water weighs 88 pounds per cubic foot. That means 100 cubic feet of displacement will float four tons. What sorta water you guys have? last I looked it weighs 62 lbs per Cubic Ft...

With all the gabbing going on about floatation, I really wonder about the construction of these boats your fooling with, or is is INTENTIONAL SWAMPING that is being planned??

[Wild Dingo]

strewth! man I figured the whole question had been answered amiacably and quickly seems I was somewhat wrong eh? no worries

Initially I was just curious then with responses made and accepted I am content to keep the stuff for other things... then I wondered about inserting it into the fore an aft baulkheads of a canoe wherein I thought any sort of floatation is better than none... then I figured ah well nothing ventured nothing gained question asked question answered thanks given and so the thread drops

ah well tis good to have created a topic that offers opportunity for discourse :cool:

Cheers!

[Gary E]

Originally posted by Wild Dingo:
then I wondered about inserting it into the fore an aft baulkheads of a canoe wherein I thought any sort of floatation is better than noneI agree with you and if shoving in a canoe is all your gona do...fine, I'd maybe do that too...

But some of these guys seem to want to use it to protect a 4 ton boat from sinkin...and I think that is a waste of time..

[Canoeyawl]

I have experience with a couple of Drascombe boats, a Lugger and a Coaster; Both boats were FG and used exclusively that type of foam for flotation… they were designed as trailer sailers and not expected to survive long-term immersion. The stuff in the forepeak was just broken up packing crates thrown in there loose, no UV exposure, and no easy way to get it out. There was more of it under the seats; it was wrapped in clear plastic sheeting (presumably to resist chafe and UV exposure) and held in place with string! The string was held to the underside or the decks/seats with glue. These boats were built in the 70’s and after 20+ years the stuff that was wrapped in clear plastic was degraded some and the plastic wrapper was finished (the string was fine!). It was positive floatation at a cheap replacement cost and held up very well. I suspect that there are still plenty of these Drascombes around with the original foam floatation.

[cs]

Did I miss it or do nobody mention something about open and closed cell foam? Seems that there is a difference.

Chad

[Gary E]

Geeeze you wana get technical...

This is just about like Dave Leterman playing
"Will it Float?" :D :D

[JimD]

What sorta water you guys have? last I looked it weighs 62 lbs per Cubic Ft...
They got heavy water :D Fresh water is around 62. Salt water is 64.

[RodB]

If you research this forum or the Coast Guard sources on foam for flotation you will pretty much find the recommended #1 choice is closed cell polyethylene. I think the type of foam you mix two parts comes in as 2nd choice. Styrene is definitely described as the worst as it just takes on so much water. I have a pretty good folder on flotation foam and sources.

I was able to contact a local company that sold 4' X 8' X 2" sheets of closed cell Polyethylene (and other sizes) for about $35ea...I sweet talked the secretary out of a very very large bag of scraps for $15...which I used about 10% of in my skiff. I have plenty left. I just stuffed it into sealed up compartments and expect it to do well. I thought about enclosing it in plastic bags, but decided it was not necessary as my construction seems quite well sealed up.
RB

[Ian McColgin]

Dan must live in an interesting part of Oregon. When I lived there salt water weighed nearly what it does here on Cape Cod, about 64# per cubic foot. Most fresh water at or near STP is around 62# per cubic foot.

Ah. I see Gary wondered also.

[formerlyknownasprince]

Hey fellas - water weighs one kilogram per litre. Yah don't even need a calculator for that one! :D

Ian

[Dan Hobson]

Thanks Guys I'm glad I made a big error like that so all you guys could poke fun at me. So my off the cuff figure for the weight of water was wrong. That means all those silly figures were off by 25 percent. One hundred cubes is only three tons and so on from there.

This only means more foam to do the job, and less storage space in the boat if foam is used.

And I still think that a super tough hull and an inflatable system is the best thing going.

The mates they beat us to the wash, and over the side they went my gosh!
And that's the end of the tail about the Yanky doodle ship!
The battle whip without a shirt
a dirty purple shirt!

[Bruce Hooke]

While floatation pretty clearly makes a lot of sense for small open boats, I stand by the general opinion that on larger boats it simply is not viable. Foam takes up too much space and inflatable bags just do not sound workable!

On a boat with an inboard motor or more than a minimal amount of ballast I think it makes more sense to depend on solid hull and deck construction, good drainage for the cockpit, good pumps, and so on. Watertight bulkheads are another fine solution if the design is suited to them.

Of course for some boats, such as small, undecked inboard launches, the best solution is likely to be a well-built and well-maintained hull combined with not venturing into waters that the boat is not designed for and in which the boat could be swamped by a wave. Some boats simply are not suited to anything other than relatively sheltered waters.

[Gary E]

Originally posted by Dan Hobson:
This only means more foam to do the job, and less storage space in the boat if foam is usedYeah...datz da problem, your reducing the space reserved for BEER !!!! :D :D

[Dan Hobson]

Size Matters.

But I've read one article about a type of fail safe device that can be manually activated and deploys from a locker.

I found the article on the rack about five years ago. They've got it on the net here:

http://www.bwsailing.com/PDFs/Unsinkable_bws%20ja98.pdf

There's a section in there that describes the Yaghtsaver system that's based on 5'x4'x3' bags inflated with Co2 that give one ton of floatation each.

All of the math about how much water from how big a hole is covered and how to prepare for these little things.

There's a section in there about foam too.

[Dan McCosh]

If the stuff is made of lots of little balls, it is likely what foam coffee cups are made of. It is usually too soft and crumbly to make decent floatation blocks. The photo looks like closed-cell styrofoam, which is a good floatation material. This would be ususual for packaging, however.

[Wild Dingo]

Dan McCosh... can you explain with pics if possible the difference between closed cell styrofoam and the stuff made of little balls?

This stuff is hard as... it can be cut however with a stanley knife and when it is cut there are small balls tightly packed (and I do mean tightly) together as I said it has what appears to be some sort of coating over it I guess to hold the shape when these were cut only a few small balls fell away (exactly 10 out of the possible 1000s that could have and I was not gentle with my hacking either)... the blocks I show are only an exaple of the shapes it has come in.. some I have cut just seem to crumple into a million balls goin everywhich way but these and some of the other larger peices hold together very well.

As I say I wont use it as Id loosely thought of as a possibility however I would like to close this with the info on which one it is... I think I will just use it to make young Josh a couple of catamarrans to sail in the pond and down the creek! :D

[ 08-24-2005, 11:47 AM: Message edited by: Wild Dingo ]

[TimothyB]

Dingo, you could always try sealing the blocks with liquid neoprene roofing material. That stuff is absolutely waterproof and UV resistant. Last time I checked, it was pretty cheap.

I don't agree that flotation is too much trouble on a heavy boat though.. the problem is not getting enough flotation in usable space, you can get gobs of it with inflatable bags and scuba tanks. The problem is reliability and deployment of that sort of system. But that can be designed with failsafes, fastening points to floors or deadwood, etc. It has not been too commercially viable because of the cost of these systems. Really reliable systems costs bucks, and people rarely think they will be the one to need something like that.

Dr. Bob Griffith, an SSCA Blue Water medal winner, disagreed, in a sense, with that sentiment. To paraphrase him, he said he was absolutely convinced that if you sail long enough you will lose your boat, and you have to plan for that.

I think that if I were going serious blue water cruising, and I didn't want to lose my boat to anything other than complete destruction, I would fit my vessel out with a carefully designed flotation system.

[Dan McCosh]

Regular styrofoam is made by foaming up resin--when you cut it , it looks like a cellulouse sponge, with lots of little cells, rather than distinct "balls" that crumble. The other stuff is made by pressing the balls together under heat, which creates something that is like a lot of hollow BBs stuck together. It's hard to tell the difference from a picture.

[Wild Dingo]

No worries mate... what if I try a different angle or closer a bit more light perhaps? mmm a cut peice? will do but you will have to wait for a bit as its rainin... again :rolleyes: