Closed Cell Foam

[ptitterington]

Hello I hope someone can help.

I have purchased an Orkney Dory 16ft. I have cut away sufficient of the deck to remove all the saturated foam and half assed repairs using non closed cell.
It filled about 8 dustbins so I recon I will need about 350L to complete the job.

I live in Jersey Channel Islands and will need to get the foam shipped, or I can get it delivered to family in the UK and collect on one of my trips over with my van.

I have been unable to locate a UK supplier.

I would appreciate any assistance and also any practicle tips for re-filling the hull without causing distortion.

Thanks

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[omega2]

If you have got it all out the the bottom of the boat I would not bother replacing it as the same will happen again no matter how good the foam is supposed to be. What we did with a pilot 590 was to make inner panels from gunnel to deck and glass them in, then filled those with foam so most of it is not exposed to constant water soaking, which will happen over time. The method we used to fill the voids was to cut 2" holes in the new panels just below the original gunnel returns at intervals. When it came to filling we tilted the hull and poured the crazy foam into the lowest hole and with a plasterers float prevented it from coming back out causing it to creep uphill, when the reaction stopped we went to the next appropiate and hole repeated the operation, at the last hole the foam was allowed to find it's own level and exude from the hole. This was trimmed and the holes made good with matt and resin. We suffered no distortion. We did not put the job to the test i.e try to sink it, but it stiffened up the whole boat.

<hr width=100% size=1>J HAMER

 

[domlee]

Similar problem a number of years ago i.e. how to fill a large void with foam but had limited access to the sides of the void due to bulkheads etc.

My solution was to Drill a 4 inch hole into the top of the void (used a plumbers bit to cut a clean 100mm hole and used the plug when finished tofair the deck) and the insert a heavy gauge wheelie-bin sized refuse bag into the hole and blew it up using a vacuum cleaner (this ensured the sides of the bag touched the sides of the void. (I had roughly calculated the volume of the void as to being nearly the size of a wheelie bin which gave me the idea of using the bag!)

I then gradually poured 2-part foam into bottom of the void. When the chemical reaction of this lot ceased I then dropped in some more until the void was filled. I then trimmed off the excess. The bag formed a barrier to moisture with the expanding foam pressing it against the hull.

If I remember correctly, I got the foam from a fibreglass suppliers (was it Glasplies?) but it was a messy/toxic concoction that required adequate protective clothing and ventilation.



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[maxi]

Consider filling the void with empty plastc bottles (with lids sealed on) these provide positive buoyancy without ever becoming saturated with water. You can then out in your foam around the bottles but you will need a lot less - less cost.

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[dwarwick]

domlee is correct - glasplies do supply a closed cell foam. They are located in Southport (phone no 01704 540626)
I have always found them a very helpful crew and they have copious literature on all glassfibre techniques including how to use their closed cell foam
Embedding plastic bottles in the foam will substantially reduce foam requirement and in this country you will find a vast assortment of them in any country lane.

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[aitchw]

In deciding what approach to take just remember that the foam is there for two reasons. First bouyancy and second stiffening. Leaving the voids empty will radically reduce stiffness and hull integrity but filling will always leave you vulnerable to waterlogging as I do not know of any 'closed cell foam' that will not take up water if left submerged long enough. The best bet is to ensure that there is a designed void somewhere low in the hull Vs where water can collect and where you can get at it to remove it. If you can also arrange for an opportunity to get some air flow through the under deck area by opening fore and aft hatches in the deck even better.

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[jollyjacktar]

Had similar problem with sailing dinghy. Six weeks of upending it to allow moisture to escape out a drain hole did not produce a drop of water and the thing was just as wet as before. Osmotic capilliary attraction will keep it wet for ever. My solution was to drill six inch holes and install inspection ports that allowed me to remove all the foam, with some considerable difficulty I must add. Then I filled the void with plastic bottles and blocks of polystyrene all from waste and packaging sources and packed it as tight as possible. Inspection from time to time showed no deterioration of the bouyancy materials and any surplus leakage was drained out an inserted drain bung whenever I took the boat out of the water.

I must add that strength and riigidity of the hull were not dependent on the foam material in this particular design. Since then I have always avoided anything with foam filled voids, unless it is polystyrene.

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[oldsaltoz]

G'day Peter and welcome to the YBW forums.

Are you planning to replace the foam with sheets of closed cell foam or a mix of epoxy resin and closed cell balloons? as the methods are very different, let us know what you plan to use and we can better answer your question.

I am assuming the point of entry for the water was the shoddy repairs.

You will need some closed cell balloons and resin even if you plan to use sheets of foam.

Avagoodweekend............



<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.

 

[ptitterington]

Many thanks to all for the replies and the welcome.

The boat was left on a mooring and that combined with some poor repairs allowed the foam to become saturated.

I am intending to only trail the boat and have made the trailer.

I have probably cut away 80% of the deck and my intention was to put marine ply and re-glass in a complete new deck.

I intend to use the 2 part expanding foam, my father used it years ago on boats he made but has since only used Boston Whalers which I gather hold the 2 sections in steel supports that fit the top and bottom section of the hull while the foam expands and allows no distortion.

I have noticed that with the foam and deck removed, the boat is obviously much less ridgid.

I have rinsed and rinsed the inside and it has now been stored upside-down for a couple of months. I intend to repair some of the hull damage from the inside then fit the ply, foam fill and then re-glass, taking new ply and glass up the transam which also was cracked due to an oversized engine being used.

I just need to not add too much weight to the boat in my keenness to make it strong.

Thanks I will follow up the number supplied for the foam.

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[ptitterington]

I have just spoken to the company that supplies the foam, 2 types, high or low density, for boyancy I need low density but it apparently is very fragile and any flesing of the grp will crush it.

So I guess I will need a rethink.

Some foam more grp and ribs to support the deck.

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[oldsaltoz]

G'day Peter,

Looks like you have reached the cross roads, and have to decide if she is worth fixing as the 'fix' may be a bit bigger than the original estimate.

I doubt any of the expanding foam available will closed cell, so will turn to mush at some time down the track, and as you have discovered not all expanding foam is suitable for fibreglass sandwich construction as it crushes and provides little if any structural stiffening.

So what's the plan? You could lay up more glass below the waterline and have no need of foam in that area, or, you could cut from the inside and properly clean the inside of the outer skin and insert some closed cell sheeting and bond it with closed cell balloons or 'Q' cells.

As for the deck, ply might be a bit on the heavy side and you don't need that too far above the waterline: Again you could use foam sheeting and sand it to a perfect shape then glass over it, less weight, more buoyancy, nothing to rot and it will look and handle like the original.

But........This will take a lot of your time and some extra cash, the only good thing in going this way is that it will keep you out of the local and give you some good skills.

Keep us informed on what you plan, we may be able to help with some tips on purchase and technique.

Avagoodweekend

<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.

 

[roger]

There are various grades of polystyrene foam available from builders merchants. The better closed cell grades, referred to as "blue" and "pink" are believed to be much less likely to absorb or transmit water than the conventional "White". They are more expensive and noticably stronger too.

<hr width=100% size=1>Roger

 

[bedouin]

Does anyone know whether these closed cell foams, once wet, will drain if a suitable drain hole is provided, or will they hold the water like a sponge?

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[aitchw]

Having spent a huge amount of time drying out the foam blocks in a Sunfish dinghy I found that the water does drain out over a long period of time and benefits hugely from as much airflow as you can arrange for around it. It does not absorb the water rapidly so if you can avoid contact with standing water by leaving space at the lowest point in the cavity for water to collect you can pump/mop it out before the foam is affected. It took a full long summer with hatches open and endless mopping out as water settled out. The weight of the boat reduced by around 50lbs, quite significant in hull that was supposed to weigh 140lbs.

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[ptitterington]

Well thanks again for all the suggestions.

Well my plan, I will order the high density foam, as someone explained it may well weigh 10lb per cubic foot but seawater is sixty something a cubic foot so I will still get a lot of boyancy. I intend to lay some more glass on the inside of the lower skin and form some ribs. I was wanting to use the foam to bond the deck and hull together, but I will need to determine if I can fill the deck flush with the expanding foam and then shape and glass directly onto it.
I will certainly be introducing some drainage ducting throughout.

My biggest problem to overcome will be my laminating, I laminate flat roofs occasionally as part of my work but the tendency is to use far too much resin, A friend who used to work with me was a boat builder and he would somehow manage to wet out with the smallest quantity of resin as he was always trying to keep the weight down out of habit.

The foam that Glasplies will sell will cost £210 +vat and carriage for a 50 kilo pack that will yeild close to 13 cubic feet.

The wet foam that I dug out and filled 8 bins was certainly adding a few hundred kilos to the overall weight.
Prior to digging it out I had drilled a hole to let the hull drain for a week, quite a lot did drain out but all of the lower third was totally saturated.

I had given myself a budget of £1500.
The boat was £350 and I can try to sell the 90hp yamaha or keep it for parts for the 75 that I have and intend to use.
The trailer parts came to £450, I think I just overdesigned it a bit and have infact built a tank transporter.
So £250 for the foam, $199 for the GPS Fisfinder big saving getting it direct from USA Eagle Cuda 240.
So apart from time and sundry bits I wont be too far away.

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