waterbum

Over the winter I decided to remove some rotten wood from the cabin. One thing led to another (rot hiding rot) and before you know it I spent 60 hours removing 90% of the wood in the cabin. It is an older Fountain 10 Meter and one of things I noticed is that all of the compartments under the flooring were empty. Before I glass things back up should I consider adding floatation foam? Not that I ever want to take on enough water to sink, but if it happened it would be nice to not have to go to the bottom of the lake to retrieve the boat. Would it also help dampen noise? I start glassing next weekend so this is my chance. I also noticed that each compartment was completely sealed. No drain holes to the bilge. Water came through rotten parts of the floor into various compartments and sat there for years or until it evaporated. Is this a good design or should I allow each compartment to drain somewhere?

Thanks,
Doug

tcelano

That is odd to have isolated bilge pockets with no drains. I see no drawback whatsoever to foaming these pockets except the slight weight addition; after all, there are many boats that are built this way from the factory. I'd go ahead and provide a drain to the bilge too. No need to carry around accumulated water.

32storm

The foam will dampen some hull slap noise. It will also stiffen up areas where the hull may be flexing as well.In theory it does add flotation, but short of extensive foaming thru-out, I don't know if just doing the cabin area would keep it afloat.

The foam will hold water. In fact, some boats over an extended period of time end up with rot due to the foam holding water.

If you are going to add foam, may want to check to see possible sources of water. This would include any cabin hatches that could potentially leak. You should have drain holes to allow water to flow back to the bilge and drain. If you decide to foam, make sure you have the drain provision.

waterbum

Thanks for the info. The source of the water was primarily from the hand rails on the bow. The sealant had aged and became brittle. There are 6 bolts holding each railing. Over the course of several years, these were leaking slightly. The most extensive rot damage was right underneath each bolt (some worse than others). It was not until I pulled the carpet back and started removing sections that I saw the extent of the damage. I think I'll add the drain holes, but leave the foam out. We had an older boat with foam that got wet. It never dried out once it got wet. It just got heavier and heavier.

Thanks,
Doug

bryanspeedracer

I have the same boat with the same design. None of my cabin stringers had a drain either. Fortunately, the wood/glass is in good shape. The only area that I can't get to is where the tanks are (without removing them). It seems to drain ok, just alittle slow.

Good luck,

Bryan

z.zuperboat

Make sure that when you add the foam you have the proper temperature.I've heard of foam jobs that have been done in cold weather, it got warm and kicked again, got big and distorted the bottom of the boat.

Chris Sunkin

You have to be very careful and inject foam into enclosed cavities in stages, allowing expansion and curing at each step. If you injected an enckosed space in one shot, it may cause damage and/or delamination- some foam really expands- especially the 2-part types which are the one's you usually find in volume. I discovered this the hard way.

The reason there's no foam in those areas is that the amount of foam needed to keep the boat afloat would displace half your cabin. It would be virtually impossible to achieve "level flotation with all that weight on the transom and no space for flotation back there. If it did float at all, it would bob up and down with the bow pointing straight up so you couldn't even hold on while waiting for help.

Good foam in the quantities you need would be pretty pricey- I'd spend the $$ on better insurance coverage and not sweat it.

Didn't at one time someone offer some sort of anti-sink airbags for sport boats? For that matter, just stow one of those self-inflating rubber rafts in the cabin- pull the string before going overboard!

waterbum

Yea, I think I'll skip the foam idea. They just looked some pretty big cavities not being used. I had seen foam in those areas in smaller boats and thought it might an option. At this point I just want to get it put back together so I can go boating.

Thanks,
Doug