Filler to level out low spots in bilge?

[ssullivan]

I have an "interesting" design in that they left a couple of "swimming pools" in various areas in my bilge. One is under the aft stateroom berth. It's a great place. I hear mold condos are going for $350K these days there.

So I'm looking to fill in the little lake back there and keep any water moving down to my main bilge.

The "lake" in question is the interior of a very shallow skeg just before my rudder. I have a couple of other spots water can collect as well that I might fill in.

Question is:

What would you use to fill in these spots?

I was thinking of using that floor leveler used in construction - it's part cement, part plastic. However, I don't want it expanding during setting up and breaking apart the hull, nor do I want a great amount of extra weight in the stern (already have a genset, tender and outboard back there).

Any ideas on a good material that isn't expensive and won't expand on setting?

[mike d.]

sean i have G.S. 37 and my prob is in back of the rudder post support. my solution was to stop the water from getting in in the first place. i rebedded every thing aft where the water was coming in from. now all is well! are you getting water in or is this just in case? my little ponds had standing water after i flushed out that part of the bilge area. i just scooped up what i could let it go to the pump sump, and the rest evaporated. othe than the sump my bilge is now bone dry. if your area in question is where the skeg mount bolts come thru i wouldn't use the type of stuff your talking about. i would dry it thoroughly and then use a silicone or something similar to fill the void so you can get it upif you need to and if it's clear stuff you can keep an eye on goings on under-neath.

[ssullivan]

Thanks for the reply, Mike.

The water has come in from time to time from the lip around my aft locker. See, the drainage system there gets plugged up every once in a while, so all it takes is one rain shower to fill those little bilge pools up. Once full, they do indeed evaporate, which causes mold problems.

My goal is to eliminate the possibility of any standing water anywhere except the "sump" bilge where the bilge pump is located. Mostly this is in order to keep the humidity from the evaporating bilge water down to a minimum.

I was definitely leaning toward some kind of soft filler (such as silicone) after considering the pitfalls of filling in with the floor leveler.

The area is forward of the rudder stock and has no logical use, except if you wanted to bolt a skeg there. Other than that, it's just an empty fiberglass box. I think it's there to help with directional stability (espeically downwind). No bolts, no nothing, but I like the idea of being able to use something soft so that I could bolt on a skeg if I so chose. Good thinking.

[Pura Vida]

Sean,

How big are the pools? More than a liter? What are their shapes? W?der than deep. Could you fill them with packing peanuts or expandiing foam and then glass over the top?

Or... Cut a piece of marine ply, and glass in a cover. If you ever need access, it could be ground out.

[Shas]

I'd be afraid of concrete-type construction leveler.
When the boat flexes, and they always do,
this stuff will crack and break if the boat is stronger
or will make a "hard spot" on your hull if the filler
is deep enough to make it the stronger.
Either way I see only disappointment.

If the low spots are more than a few litres in volume
I like the idea of glassing in a cover piece.
I wouldn't use plywood, though, unless I was confident
that it was going to stay permanently dry.
It isn't difficult to make a GRP panel for the cover.
Just cover an appropriately sized flat surface
(eg, plywood laid across two sawhorses)
with waxed paper or some other easy-release substrate
and wet out several layers of glass cloth or roving
until you reach the desired thickness.
Next morning you cut it to fit and glass it in place
with glass strips and resin around the hull/cover joint.

My own bilge required some serious levelling
and that's how I handled the deep bits.

For shallower areas I mixed resin with styrofoam beads
and poured/troweled that to the level I wanted.

This is simplified a bit, of course.
If working with GRP is a new technology for you
I'd be glad to exchange detailed info via email.
I'm no expert but I have learned a few things the hard way.

The hardest part of building your first boat...
is building so much of it TWICE!

Shas

[SkiprJohn]

Great Stuff Insulation foam in a can is what I'd use. You can always dig it out if need be and it will keep the water out. Just fill it and then cut or grind away the lumps and bumps you don't want protruding.
Regards,
JohnL

[delmarrey]

FiberLay makes a fiberglass filler. Basiclly it's ground up fiberglass mixed with a polyester jell. Just add the hardener and mix and spread. It can be bought in quart cans or gallons.

http://www.fiberlay.com/

Fillers & Additives--part # 6124040
.................................................. ._/)

[Alan Wheeler]

I did ruffly what you want to do. It was in some very large lockers in the Pilot house. The floor had a slight curve in the plywood due to weight of stuff stacked in there. So I decided to fill the floor level so as any water that does get in, will flow out and down the cockpit drains. I simply used Epoxy Resin and filler/fairing powder. I mixed up a very liquid brew of the stuff and poured it in. Careful not to do it in to thick a layer at a time. A big deep area of it can over heat and boil. I poured about a 1/4" deep layer over an area of 8ft x 3ft and it self levels out and then hardens. Worked great.

[coot]

Originally Posted by SkiprJohn

Great Stuff Insulation foam in a can is what I'd use. You can always dig it out if need be and it will keep the water out. Just fill it and then cut or grind away the lumps and bumps you don't want protruding.

Does it stick well to the fiberglass? I thought of that foam, but I wondered if it would separate from the fiberglass, leaving a tiny void between the foam/fiberglass that would allow water to get in.

[Boracay]

If the space to be filled is not more than a couple of litres you could consider mixing epoxy resin and mirospheres to the consistency of a pourable mix.

Clean the areas as much as possible so the resin sticks.

A possible problem is the resin/microsphere mix not coming out level, so some way to spread it evenly (spatula) may be necessary.

After it sets I would consider painting more of the resin on top and up the sides to make sure no water works its way down the side.

[GordMay]

First, remove any paint in the bilge area to be filled, and/or scuff up any gellcoat, to provide a "tooth” for the new filler to adhere to.

Next, thoroughly dry out the hull. If the hull isn’t completely free of internal moisture when you start, you'll actually seal the moisture in.

Then, trowel in your filler* of choice. Remember, you’ll want to establish drainage towards the bilge sump.

* Don’t use a porous filler, such as foam. I agree with the others who suggested a thickened epoxy.

Finally, consider applying a barrier coat overall.

[cooper]

l would sugest going the way of epoxy and filler. Becarefull of what type filler you use though. You need to use a "Fairing" type or you could be in for a lot of work. Microspheres can be very hard to sand. The self slumping idea of wheels is a great idea. It efectively does the job you need all by itself. To get the epoxy to stick first thoughly clean the area to get rid of any residual oils, then abrade the area with 60-80 grit paper (dont forget your mask) whenit comes time to epoxy brush on a thin coat of neat epoxy and let it go tacky, then pour in your mixture. If you are pouring it in layers (to avoid heat build up) then pour subsequent layers before the last layer has completely hardened. Finnaly you will need to coat the surface with at least three coats of neat epoxy. This is because fairing fillers (and a lot of others too) will hold water and are not classed as water proof. This system will give you a strong, very light, water proof job that will last as long as the boat.

[Sandero]

You can find an epoxy based pourable self leveling products... google it dude.

[Mr. Fixit]

It was necessary for me to level 2 places, one for a fuel tank, another for a battery box. The method I used FWIW was first I prepared as GM suggested above, next came a coat of epoxy, followed with filler material composed of perlite and portland cement (applied while epoxy still tacky) after drying to 6% applied epoxy and fiberglass cloth to enclapselate. I am NOT an engineer and as a result did not consider soft spots, hard spots etc. and am not recomending that any one else use this system. I am very familar with perlite/portland mixtures as this was one method used to pitch level roofs to roof drains (prior to tapered insulation). Perlite is also used as the aggregate in gypsum plaster (Structolite). Very cost effective and available.