Adding weight down low...

Discussion in 'Stability' started by souljour2000, Aug 11, 2009.

  1. souljour2000
    Joined: Aug 2009
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    Location: SW Florida

    souljour2000 Senior Member

    Hey everyone..I am weighing the idea of picking up sandbags to put down in the lazarettes of my H20 swing keel..there are alot of these compartments which are about 15 inches deep and they are scattered from under the stern quarter births to the area under the v-birth...I am considering this because when I went camping last month for 4 days and had alot of gear the boat seemed to really like all that weight without affecting speed much at all...at least when I had good wind...not sure why this happens other than centrifugal force can give a smaller boat some edge into the brine that is just more noticeable than with bigger boats due to their overall size...anyway...the boat has a 400 lb iron swing keel and a very flat rear-end to start with...fractional rig and the original long, skinny mast for its size...29.5 feet....I am thinking about 200 lbs worth of bags..what I am wondering is will this make my boat that much stiffer...honestly, I don't put the keel down unless I need the tracking badly...so what I am hoping is that the weight will be low enough to steal me a little more righting moment too.
    Also...When under power what is the tradeoff with weight vs. the benefits from better wave-breaking ability and less slap down?...In other words...you are burning more gas with
    the extra weight but you are also holding a straighter course over a long distance and using the boats new extra weight to shoulder thru waves more easily...does this all make any sense whatsoever..if so...sorry for the Gettysburg address post...I appreciate anyone''s experience or views....
     
  2. ancient kayaker
    Joined: Aug 2006
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    ancient kayaker aka Terry Haines

    I don't know the H20, did you do a net search for information? The only thing I could find related to this suggested you should keep the extra weight forward.
     
  3. souljour2000
    Joined: Aug 2009
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    Location: SW Florida

    souljour2000 Senior Member

    Hmm..weight forward..huh...there is very little about hunter 20's in any of the whole internet..they we're not a very sought-after design at anytime..they suffered from immediate huge flaws with the keel rope sheave design that pretty much took the wind out of the sails of the launch and that was that...there are a few around though...they are not very fast and I think they are very comfy really the way they were set up...I am having to do some "modifications where I can get away with it"...they handle fairly well though and are good boats to break out of the "16 and under club with"....
     
  4. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Adding weight is taking the "liveliness" out of her. This could appear to be a good thing, the motion becomes calmer and more comfortable, she feels more solid and steadier, with a general "bigger" boat reaction to the sea state.

    On the other side of the coin, the weight is slowing her down. She'll accelerate and maneuver more slowly and will be less sensitive to helm inputs. You'll lose some adjustability in the "groove" and the boat will become a more docile version of itself.

    The boat is designed to carry a modest crew load , so you may which to carry this (640 pounds including yourself) to bring her down to her lines. I'd add this at or near the bridge deck as low in the boat as possible, maybe at the aft end of the centerboard case will be good.
     
  5. ancient kayaker
    Joined: Aug 2006
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    ancient kayaker aka Terry Haines

    The weight forward suggestion I came across was to get the bow down when carrying in crew in the cockpit, presumably the normal place. The guy had noted that the bows were raised and seemd to feel the weight forward may have increased the boat's speed by increasing the LWL. If this is a tendency of the H20 it may be smart the keep an eye on the boat's trim.
     
  6. souljour2000
    Joined: Aug 2009
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    Location: SW Florida

    souljour2000 Senior Member

    That's interesting AK...actually my 12-year old was up near the bow spotting tarpon as we ran down the beaches ...He's a bit heavier than average for his age ..maybe 130-140 lbs and with the seas only 1-2 feet we were not plowing at all but the extra waterline should have added a bit of speed..it seemed we were doing quite well in say 8-11 knots of wind max... and especially with all the weight of water (20 gals.) food, some gas, gear for 4 days and a 5hp Tohatsu on the end...not too mention the fairly heavy dinette table/berth. Anyways..thanks for that info AK...makes alot of sense...
     
  7. Tom.151
    Joined: Jul 2009
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    Location: New England, USA

    Tom.151 Senior Member

    As an alternate direction, or for testing various configurations... 4 5-gallon jugs would give you prox 160# of weight.
    With water containers (of whatever size) at least you can evaluate things simply by filling/emptying them whenever you want to adjust ballast weight. Maybe easier than using sand for the weight.
    You can even shift them all to the windward side when you have ;little or no crew available ;)
     

  8. souljour2000
    Joined: Aug 2009
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    Location: SW Florida

    souljour2000 Senior Member

    Thanks for the feedback Tom...5 gallon jugs I have not tried, probably because they are pretty big for the size lazarettes I have...but on that 4-day trip I did use over twenty 1-gallon water jugs with screw-type lids..and some 1-gallon orange juice jugs.
    Lately, I save any sturdy polyethylene jugs like the plastic tropicana juice jugs ,and some of the Ocean spray 1-gallon cranberry juice jugs which are very sturdy and have screw lids. I can fit these all over my boat...in various spots with a whole bunch of them under my main bunk. Then when empty I can toss them out of the way behind the companionway steps and into the large space I have under the cockpit floor that is underutilized so far. It's easy to just grab one of these jugs as I need them...and I guess I get some emergency flotation by having the empties piled under there...throw a rope thru a few of those in an emergency and you have some extra flotation..
    The Hunter 20 water tank was kind of a joke in terms of capacity and it leaks now..so I just converted it to use for dry food /kitchen item storage.
     
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