Bilge Depth

[cklanac]

How much bilge space is too much? When is it just wasted space?

I have a 1986 Morgan 43CC, the fuel tank (40gal) is under the port settee, I'm considering removing it and building two smaller tanks (total capacity !~60gal) in the bilge. There is plenty of space just forward and just aft of the mast. The lower center should theoretically improve sailing characteristics even if just slightly. But I'm worried I won't have enough bilge space... Is there a good rule of thumb to go by?

-ck

[gonzo]

"Canoe body" designs have no bilge to speak off. If any water gets inside, it sloshes all over the interior. At the very least leave enough depth for a well where the bilge pump is.

[cklanac]

Thanks. My thoery is... if I have a hole big enough to worry about bilge capacity, then I probably have more important things to worry about, like keeping her afloat.

[gonzo]

On very shallow hulls, rain water or spray is enough to get everything wet.

[PAR]

I haven't seen enough bilge in a current design in quite some time. You can have too much, I'd guess, but I always design enough for pots, pans and such on a cruiser hull form.

Deeper bilges can help motion in a big sea, though the modern thinking is to have as little belly as practical for best performance.

Most folks don't use their boat for long enough of a stretch to worry about the amount of bilge room. In this vain, there seems to be woefully little general stowage in modern yachts. Packing off to sea for extended cruising can be difficult with stores enough to carry you through in shallow bellied craft. Designers are now sealing the bilges to the hull to keep bilge goo from washing down the contents of lockers!

[SailDesign]

Originally Posted by PAR

Designers are now sealing the bilges to the hull to keep bilge goo from washing down the contents of lockers!

The practical aspect of which is that the extended sole under the seat/locker/berth/whatever that is attached to the hull becomes a "free" stringer.

Waste not, want not. Recycle, re-use, etc.



Steve

[SeaDrive]

Originally Posted by PAR

Designers are now sealing the bilges to the hull to keep bilge goo from washing down the contents of lockers!

Or, are they keeping the bilge water from washing up into the lockers when the boat heels?

[gonzo]

Without a bilge the would-be-bilge-water sloshes over the cabin sole.

[stew fl]

If there is water in it, find out where it comes from and fix it.
If you know where the water comes from, pump it out.
If it's not water it's gas or diesel fuel, RUN!
If you're electrical systems don't work it's the wire running thru the bilge that got wet & rotten so forget it 'cause you can't get to it any how.
The fastener you need to save the boat is down there but same story.
If you stored something down there use it yesterday 'cause it ain't no good today.

Thanx for listening.

[gonzo]

In wet weather water comes in from the top. There is nothing to fix.

[stew fl]

Gonzo,
I covered that in sentance two,
"If you know where it comes from pump it out"

Thanx, STEW