How do I build up the bilge level?

[Niffler]

I have a bilge and shower sump that works really well, most of the water runs in there and gets pumped out, but the surrounding area is half an inch above it in areas so some of the water hangs around there, rather than running into the sump. I want to build up the level around the sump by about an inch so that it's way above the sump and make a little valley so that it guarantees everything drains straight into the sump. What should I use? The base is GRP with bilge paint and of course I'll need to completely de-grease it so I assume white spirit for that? The area is about 60cm by 50cm. Thanks.

 

[rich]

I have seen pitch used on wooden boats.

 

[Kelpie]

I have a similar issue with my anchor locker, there is always a pool of water in one corner. I was thinking of using some cheap car body filler, easy to work with, easy to sand smooth, my only worry would be if it didn't bond well enough to the existing gelcoat and then allow water to get behind it.

 

[Niffler]

I thought about that but it's a lot of material and the exoteric reaction could be impressive. I did think about filler foam, smoothing it as it dries but I think it could still end up lumpy.

 

[Kelpie]

What about using some foam, either squirty type or a block of Kingspan, carve/sand it to shape, and then glasscloth over the top?

 

[PlankWalker]

If there's large quantities involved and commercial filler a bit pricey.
It's easy to make your own very cheaply using polyester resin, hardener and then stir in talk powder to the consistency required.

Plank

 

[Malish]

What about using some foam, either squirty type or a block of Kingspan, carve/sand it to shape, and then glasscloth over the top?

+1 use some ethafoam from unwanted packaging, pieces will glue together and can be cut easily. Flowcoat or epoxy and glass to finish

 

[Niffler]

If there's large quantities involved and commercial filler a bit pricey.
It's easy to make your own very cheaply using polyester resin, hardener and then stir in talk powder to the consistency required.

Plank

in even smallish quantities, epoxy hardening can get quite hot, is the same true for polyester resins? I once mixed a jam jar sized pot of epoxy and it got so hot I couldn't hold it.

 

[PlankWalker]

polyester doesn't get so hot as epoxy,
I've mixed up about 1L batches of resin making up half a bucket of filler and spreading it an inch thick with no problems,
you need to knock up a cool mix anyway as it takes some time to stir in all the talcum powder.

Plank

 

[Niffler]

OK - thanks.

 

[rogerthebodger]

I would roughen the surface of the area in question then use casting resin to bring the area to the required height then cover with glass and resin followed with flow coat to seal the whole area

http://en.wikipedia.org/wiki/Resin_casting

 

[Niffler]

Just checked on your wiki link then on ebay and that is a perfect solution for the problem, thank you very much.

 

[oldsaltoz]

in even smallish quantities, epoxy hardening can get quite hot, is the same true for polyester resins? I once mixed a jam jar sized pot of epoxy and it got so hot I couldn't hold it.

That is why we always tell people to use wide shallow containers, Ice cream or take away food containers can work.
The larger the surface area the better it cools, or in this case prevents it getting hot in the first place.

Good luck and fair winds.

 

[oldsaltoz]

I have a bilge and shower sump that works really well, most of the water runs in there and gets pumped out, but the surrounding area is half an inch above it in areas so some of the water hangs around there, rather than running into the sump. I want to build up the level around the sump by about an inch so that it's way above the sump and make a little valley so that it guarantees everything drains straight into the sump. What should I use? The base is GRP with bilge paint and of course I'll need to completely de-grease it so I assume white spirit for that? The area is about 60cm by 50cm. Thanks.

G'day Niffler,
You need to to this right the first time, so only needs doing once.

Using a standard Poly resin might work, but an Epoxy will work.

A mixture of Micro Balloons and epoxy mixed to the consistency of toothpaste will be easy to lay and level.
Problem is, it will probably outlast the rest of the craft.

Simple steps are: clean and degrease the area, sand with a 40 git, wipe clean with Acetone.
Apply a thin continuous coat of epoxy resin, them mix your epoxy and balloons when the primer coat is still tacky (about 45 minuts on average).

Good luck and fair winds.