[Public-list] Cockpit drains above water line

Roger L. Kingsland r.kingsland at ksba.com
Wed Mar 14 06:33:17 PDT 2007


Great info Gord.  I guess the forward cockpit drains don't "regurgitate" 
because the wave trough (in which a displacement boat finds itself at hull 
speed) is deeper further forward resulting in a concave (or is it convex) 
waterline higher at the ends.  Sounds like time to reorient innovation 
efforts back to the steam propulsion scheme.  I think this one 
http://www.neofuel.com/moonice1000/ has some promise for adaptation to the 
A30.

On the weight distribution thing, I have made two, 20 gallon+/- tanks under 
the aft ends of the V berths and was planning on abandoning the original 30 
gallon tank forward.  Maybe I should fill them all and see how she schoons; 
or, fill the forward tank and transfer water to the windward under berth 
tank (that would be 415 pounds forward, 170 to windward).  Of course, if we 
get thirsty, the whole scheme goes asunder.

Have a good trip.

Roger 148

----- Original Message ----- 
From: "Gordon Laco" <mainstay at csolve.net>
To: "Alberg 30 Public List -- open to all" <public-list at lists.alberg30.org>
Sent: Wednesday, March 14, 2007 8:33 AM
Subject: Re: [Public-list] Cockpit drains above water line


> Good morning -
>
> Ah Roger - you remembered that story!  Hard to imagine that the night that
> was used was 24 years ago!
>
> I think that drains straight (or slightly inclined) out the rear of the
> cockpit would result in the aft part of the cockpit flooding when the boat
> was at or near hull speed.  Our boats tend to squat and as speed increases
> the squat gets worse... Over 6.5kts the lower part of the transom is under
> water.   Lay a ruler on a drawing of the boat and you will see what I 
> mean.
> Be aware also that the aft at-rest waterline is significantly higher on 
> our
> boats than what is shown in the drawings... That is because the engine is
> heavier and that old bugaboo... The change to iron from lead ballast 
> shifted
> the centre of gravity slightly.
>
> If I somebody has already done this and proved me wrong please chirp up. 
> I
> have often thought about ways to improve the drainage (too old and mortal
> now to rely on the 'old technique') and the aft method is one I have
> considered.
>
> Just heading for the airport to go to Maine - hope to see some Albergers 
> at
> the show.
>
> Gord #426 Surprise
>
>
>
>
>
>
>
>
>
>
>> Hi Rachael,
>>
>> I haven't tried it but am glad you asked because I thought about a 
>> similar
>> arrangement only locating the drains at the aft corners and running them
>> horizontally (or slightly downward) straight aft through the lazarette. 
>> It
>> might be possible to glass in some kind of flange at the bottom corners 
>> of
>> the lazarette bulkhead (tangent to the cockpit floor) which would get the
>> hoses a little higher.  To get drainage while healed, I think it would be
>> necessary to, A) have two exit points with each slightly below and 
>> outboard
>> of the outboard edge of the cockpit floor; or B),  have a combined exit 
>> at
>> the centerline low enough that it is below the outboard edge of the 
>> cockpit
>> when the boat is fully healed.  I have a plan to make the lazarette
>> watertight from the rest of the boat (and perhaps self draining) so if 
>> this
>> type of drain leaked it wouldn't fill the boat and cause a potential 
>> "glug,
>> glug".  I don't know if there would be any problem with backwash in a
>> following sea.  One plus would be the hoses could be much bigger allowing
>> the cockpit to drain faster.  Of course, Gord Laco seems to have the 
>> fastest
>> cockpit draining technique of all.  Just put the spreaders in the water 
>> and
>> let it pour out over the combings.
>>
>> Roger 148
>>
>> ----- Original Message -----
>> From: "Rachel" <penokee at cheqnet.net>
>> To: "Alberg 30 Public List -- open to all" 
>> <public-list at lists.alberg30.org>
>> Sent: Wednesday, March 14, 2007 12:02 AM
>> Subject: [Public-list] Cockpit drains above water line
>>
>>
>>> Hi folks,
>>>
>>> I'll be replacing my cockpit drain plumbing soon - I plan to remove the
>>> current gate valves and through hulls.  I'm pretty sure I'll also
>>> replace the drains in the corners of the cockpit with larger ones - the
>>> originals look to be 1" or slightly less.  I like the 1-1/2" bronze
>>> Perkos (installed them on another boat), but will have to make sure the
>>> above deck flange fits - I think it will.
>>>
>>> Anyway, on to my real question:  I'm thinking about plumbing the
>>> cockpit drains so they exit above the waterline, and I'm wondering if
>>> anyone else has done that.  I did search the list archives and find a
>>> couple of posts from 2002, in which the idea was discouraged, but
>>> nothing since then.
>>>
>>> I've nothing against through-hulls in general, as I believe that good
>>> quality seacocks, well-installed, are fine.  On the other hand, cockpit
>>> drain seacocks are the one case in which you cannot close the seacock
>>> when the boat is unattended, and certainly no seacock is as safe as a
>>> solid spot of glass in the hull :-)
>>>
>>> Crude measurements show that there is probably something like 8+" from
>>> the cockpit drain holes to the resting waterline.
>>>
>>> I did quite a bit of cruising on a boat that had the cockpit drains
>>> exiting above the waterline (not an A-30), and it worked pretty well.
>>> They left the cockpit in the front corners - like on our boats - and
>>> then hoses ran aft and exited the hull on the transom near centerline;
>>> in this way they avoided the problem of dipping below the waterline
>>> when heeled.  As a side bonus, the deep (below waterline) galley sink
>>> drained by being pumped into one of the scupper lines (with a manual
>>> bilge pump).
>>>
>>> I may very well replace the original set-up (but with better parts and
>>> larger lines), but there's no harm in exploring other possibilities in
>>> theory, anyway.  Has anyone run their cockpit drains the way I'm
>>> describing?
>>>
>>> Thanks,
>>>
>>> Rachel
>>> 1967 Alberg 30, #221
>>>
>>> _____________________________
>
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