Cockpit drains

Discussion in 'Sailboats' started by Steve W, Jun 13, 2009.

  1. Steve W
    Joined: Jul 2004
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    Location: Duluth, Minnesota

    Steve W Senior Member

    Can someone explain to me the twisted logic that some production builders have used when designing their cockpit drains,i offer up a little C&C 24 that i own as an example of a system which makes no sense in so many ways. First they sloped the sole towards the companionway (no bridgedeck),installed 2 x 1 1/2" drains which looks great,about a foot from the fwd end to clear a bulkhead, then merged them into 1 x 1 1/2" seacock. Now whats absurd about this is that the cockpit runs to about 3" from the transom with the back wall paralell to the transom,why the f#@% didnt they slope the sole towards the transom and put in a couple of huge freeing ports with hinged flaps to prevent any water coming back in,oh the sole is over a foot above the waterline.Ive done this on every aft cockpit boat ive built and see no reason why you would want to be making a quite large hole through the hull when you dont need to in order to provide a rather inadequate drain.My Lindenberg 26 on the other hand has 2x 1 1/2" PVC tubes running from the back of the cockpit through the transom thtough a small lazarette,a much more sensible solution.
    I am a huge fan of open transoms personally from a safety standpoint having lived with one for 20 years on a boat i designed but if you cant have this the bigger you can make your drains the better IMHO.
    Steve.
     
  2. alan white
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    Location: maine

    alan white Senior Member

    Believe it or not, it's probably because it's easier to install at the factory since the upper and lower parts of the boat have to be joined before the connection can be made. Otherwise, I don't know. It seems the shorter the run, the faster the drain time. That means drain it close to the transom, and even use two throughhulls, one for each drain. But what do I know?
     
  3. mark775

    mark775 Guest

    Its worse on most so-called battle wagons, million or three dollar boats with one objective in mind - find fish and subdue them. To do this, they are required to back down as hard as they can make the boat protest on every thirty pound sailfish with camaras whirring. If they can spill water over the transom or fill the back deck through cracks around the "tuna door" it's all the more dramatic. Of course, there are no freeing ports on most of these boats -only miniscule scuppers to be clogged up with last year's mahi-mahi parts. The thing that saves these guys is that the coaming reaches knee level (a convenient tipping point) so as to not get in the way of fishing, so if the sliding glass doors are kept closed, and it doesn't get too silly backing down for the camaras, they get by because there just isn't very much volumetric area back there. Now, if these boats are ever in a mean following sea...same thing but under adverse conditions.
     
  4. Steve W
    Joined: Jul 2004
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    Steve W Senior Member

    Your probably right Alan,im sure its something to do with the manufacture but if it were me i would have made the deck molding so the back wall of the cockpit well was closer to the transom which slopes out at the top so if you got it right it would contact it just as the deck landed on the hull flange,that way you would set it down on filler and then just rout a couple of nice big slots and save the cost and expense of the thru hull and seacock hose etc and labor of instalation,the whole point of series production is to think every thing through first and put the time into the tooling to save time on the product. I only offer the C&C as an example but ive seen this on many boats over the years an just scratch my head at the stupidity.
    Steve.
     
  5. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    Sounds to me like a classic case of afterthought:
    Marketing - "We need a 28-footer with five berths and three heads, and we want to start building next week."
    Inexperienced Designer - "I hate you...."
    (a week later)
    Shop boss - "You got those drawings yet?"
    Designer - "They're not finished."
    Shop boss - "We'll start building our moulds from what you have so far."
    (a few weeks later)
    Marketing - "Start the design for this new 31-footer that we want in showrooms in two months."
    Designer - "But the last one's not done....."
    Marketing - "The shop guys can just copy details from the last model. Get started."
    Shop boss - "Hrm, we need to get the water outta here somehow.... a couple of drains there oughtta do it... wait, there's a bulkhead in the way, put 'em there instead...."
     
  6. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    It's actually very common to see cockpits slope forward and for a good reason. In the event of a big boarding wave, the forward slope drainage will keep a fair percentage of the weight toward midship, where the displacement of the boat can tolerate it. Having several hundred pounds of water piled up against a transom is about the worst place you can put it.

    Ideally the forward drains should be in the corners, they should cross to the opposite side without reduction in line diameter and out a thru hull.

    A lot of boats can't afford this setup, there's just not enough room to have crossing drain lines sitting on top of an engine (for example). In this case they lead them aft.

    Most production craft don't have sufficient drains. A fully swamped cockpit should be able to drain off it's contents in less then a minute. A few hundred gallons of water and two 1" drains just will not do this. On the production boats I've owned, I usually added two more drains to the cockpit, which appears to be a option for you, since you have the room forward of the current drains. Open transoms are for racers.
     
  7. Steve W
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    Steve W Senior Member

    Par,i realize that on some craft there may not be option,a center cockpit would be an obvious example but when the damn thing runs all the way to the transom the opportunity to have truly large drains that will drain it in seconds without the complexity and expense of hoses through hulls and seacocks that can only do a marginal job is idiotic.The weight of hundreds of gallons of water is a non issue if it is able to escape in seconds rather than minutes.My sons boat with an open transom is a wonderful thing to live with and not just for racing,we carry a 660sq ft assym and have had the mast in the water more than once when pushing,its no big deal as it reliably comes back up but the thing that always impresses is that we never have the hatch boards in and never get a drop down below because any water we get in the cockpit is gone in just a few seconds,in fact none of us has actually seen water come in as we are rather busy at the time but we know it did because our pant legs are wet and all the lines are streaming out the back,weve seen other boats knocked down and they are pumping for their lives as the water drains down below because the drains are inadequate,another thing i like about the open transom is its easier to get the dog back on board after a swim, and also it a much safer place to take a piss from as you are standing there with a lifeline under your armpits,your not going overboard. Im of course not suggesting that every boat have an open transom,just that the bigger the drains the better,even 2 x 2" drains which are pretty expensive to install with all the associated hardware are far from adequate and most boats dont go that big.
    Steve.
     
  8. Steve W
    Joined: Jul 2004
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    Location: Duluth, Minnesota

    Steve W Senior Member

    Alan, my sons 24ft boat has a cockpit well that is 3ft x 8ft x about 1ft which would hold about 1500lbs of water and would be dangerous if not for the 3 sq ft of drain provided by the open transom, most boats ARE dangerous with much smaller cockpits as its not just the well volume but the volume to the deck level if it has combings and some boats such as the Albin Vega would be even worse as the combings are high and continue across the back. A minute to drain would seem like an eternity if you had been pooped. My C&C 24 could quite easily have a couple of 4" drains or larger through the transom with no down side that i can think of. To my way of thinking a large cockpit is not unseaworthy at all as long as the drains are large.
    Steve.
     
  9. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Large cockpits are usually considered less then desirable in blue water cruisers. Open cockpits can be advantageous, but also not practical in a deep water cruiser, particularly if you're hoping for an aft cabin.

    Most serious cruisers prefer a footwell, until they get older, then they want a big old honking cockpit with hard dodger and table to seat 8.

    I'm a firm believer in large and numerous cockpit drains. My last big boat had 4 drains added to the cockpit and could dump it's contents in less then 20 seconds, which I considered fast enough.

    Install some more drains, maybe making up your own. Another option is to cut the cockpit up and slope it the other way. You could probably make a few horizontal cuts on the cockpit seat fronts and preform this fairly easily.
     

  10. Steve W
    Joined: Jul 2004
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    Location: Duluth, Minnesota

    Steve W Senior Member

    Par, Im not going to do anything with the C&Cs drains (although i have to fight the urge), they have served it ok for 28yrs and i dont plan on keeping it,i only offered it as an example of the type of dumb thinking on the part of builders which i find very common on production boats,another i worked on last year were 2 old Ranger 26s which also had fwd drains which if i remember correctly did cross over but were only 2 x 1" going directly to through hulls with no sea cocks,of course 1" id hoses are only about a 3/4" hole by the time they exit the hull.both boats were the same so im sure that is the way they came from the builder,of course the cost to upgrade was too much. Now as you know the Lindenberg 26 has a much more common sense settup except of course the pvc tubes could have been 3" or 4" instead of 1 1/2",the labor cost would have been the same so why not. Of course when i finally get around to doing something with mine i will be eliminating that little lazarette and extending the cockpit through the transom. You are right about "Bluewater cruisers" preferring small cockpits,at least thats what i see whenever i read one of the many "what makes a bluewater cruising boat" threads on one of the forums but many of the folks who post on these threads are not actually capable of doing their own thinking and just regurgitate what they have read somewhere,sure a tiny footwell and no cockpit combings like on a Westsail wont hold much water when you get a big wave over the stern but im damned if i would want to live with that stupid little cockpit when hanging at anchor in the tropics for the few times in my life when i may get pooped,i want a giant cockpit with comfortable seating and giant drains,the size of the cockpit is a non issue for safety,the size if the drains is the problem and as you mention,most production builders just dont deal with it well, obviously if you have a large cockpit and the usual tiny drains thats unseaworthy. even a couple of 2" drains is nowhere near enough. Boats like the Volvo 70s have huge cockpits that drain fast and need to.
    Steve.
     
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