Weighted Centerboard?

Discussion in 'Capri/Catalina 14 Talk' started by c14_Scott, Jan 1, 2009.

  1. c14_Scott

    c14_Scott New Member

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    Happy New Year to everyone.

    I'm a do-it-yourself kind of person and have already installed several improvements to my 14.2.

    Has anyone considered, or ever heard of, a weighted centerboard for this boat? I'm new to sailing but wondered to myself if any stability could be gained with some extra weight as far south as possible. Since I mostly sail alone, I have less human weight to throw around for ballast (but seem to be adding to that mass all the time these days!).

    Looking forward to the return of warm days to continue my sailing education here in central VA...
     
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  2. ross ellena

    ross ellena Member

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    Centerboard

    Scott,
    I've had the same thought.
    But a D.I.Y. guy could build a light weight board with extra length/draft? The increased draft would add stability without significant added weight.
    The longer board would not retract all the way up but that could be an added benefit for downwind stability.
    You could then interchange the class legal board for racing.
    RRE
     
  3. ross ellena

    ross ellena Member

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    second thought

    On 2nd thought...Maybe the extra drag of a longer board would be just as much a penalty
    as the extra weight of a lead plug in the end of the board???
    RRE
     
  4. bananabobs

    bananabobs New Member

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    The dynamics of the sail vs the keel (centerboard) are more complex that length/weight vs sail.
    To paraphrase Sailing for Dummies, think of the sail and the keel as airfoils; the air over the back side of the sail goes faster than on the front side, the resulting difference is pressure creates lift, a force pushing the boat sideways and forward.
    If airflow over the sail was the only force involved, sailboats would slip sideways as well as forward. A sailboat however has wings above and below the water. When a sail boat begins to move through the water the underwater wing (centerboard or keel) also creates a force that, when combined with the sail force, moves the boat forward. The water passing over the back of the keel moves faster than the water on the front, again pulling the boat forward and sideways, but in opposite sideways direction of the sail force. The opposing sideways forces cancel each other out and the forward forces remain.
    For more reading on the complex physics, Google "Bernoulli" the guy who 200 years ago discovered the differences in pressure generated by fluids flowing at different speeds.
    By fine tuning the boat as it was designed, and by optimizing your experience of sail handling, you can increase the speed and control of your boat far more than weight or length modifications.
    A smooth center board, no dings or seam splits, attached debris or holes, secured and trued, as well as a clean hull and rudder will help tremendously. My centerboard used to "klunk" around while underway, securing it helped. I plan to pull it off this winter and replace the seal and I am going to reglass, sand and finish it to be the cleanest "wing" it can be. I remember doing that to the rudders on my Hobie Cat was a huge improvement in speed and handling.
     
  5. c14_JimW

    c14_JimW New Member

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    Weighted Centerboard

    Hi Scott,

    I am also new to sailing. Purchased a 1987 Capri a few months ago. After finding this site and reading the numberous occurances of capsizing by new / inexperienced sailors, I decided to figure out how to improve the stability.

    The first thought was to add water ballast bags under the seats next to the centerboard trunk. All of the water ballast bags that I found on the inter-net were either too high, too long, or too wide. If anyone knows of a specility water bag manufacturer, please let me know; I suspect the water ballast bags may be the way to go, as I understand that a lot of sailboat manufacturers are using them instead of lead and steel.

    My next idea was to make a new centerboard using one quarter inch steel wrapped in fiberglass and epoxy. Used a grinder to cut and shape the centerboard to the exact size of the factory centerboard. The final weight is 77 lbs. As I live in New Jersey, I have not yet installed it. Will give you an update in the Spring.

    Hope this helps,

    Jim
     
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  6. bananabobs

    bananabobs New Member

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    The way to improve stability is to learn how to sail the boat.

    You don't improve the braking ability of a Porsche by adding an anchor or stronger spring on the throttle return. Going too fast in the Porsche? Take your foot off the gas.

    Do not lock the main sheet, keep it in your hand the entire time. Boat rental places don't put main sheet cleats on their boats for the same reason. If you feel the boat heel too far, let it out.

    There are sailing schools every where.
     
  7. ross ellena

    ross ellena Member

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    single handed sailing

    I agree with BananaBob. The ideal option is to sail the boat as the designer intended and improve our sailing skills.
    It seems the designer intended the boat to be sailed by two people with a combined weight of about 300 lbs. Even so, the boat seems quit tippy in gusty conditions !
    I have been knocked down and turtled very quickly in gusting, shifting winds.
    Getting knocked over in warm conditions is not a big deal, if you can prevent the turtle. I found it quit difficult to self rescue the boat from upside down.
    So I definitely need better skills. But at my Sr. age, the skills are declining faster than improving. Bob would probly suggest I find a different design, but that is not of interest to me. I really like this little C14!
    I’ve read the posts on mast head flotation and can solve that issue but I could sail single handed more often (more practice!) if I could improve the stability a little.
    I like the weighted board idea for single handing. (I definitely do not like the water ballast idea as it seems counter productive.)
    RRE
     
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  8. fan

    fan Member

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    Adding a steel centerboard to a C14 may create some additional problems. 77 pounds of weight hanging on the stock cb bracket may cause it to fail under stress it was not designed for. The board may not have enough righting weight to keep the boat from capsizing. In such a capsize the heavy board might retract into the cb well unless the bungee is replaced with a line to pervent the board from moving from the down sailing position. With that, if you run a ground you now might break the cb box. Lightning sailboats have a heavy stainless steel pivoting cb and requires a preventer line to keep the board under the boat in case of a capsize or when sailing in lots of chop. As heavy as the board is in a lightning, the boat will still capsize.

    Too bad you can't weight the low end of the cb with a bulb of lead like a Melges 24 or an Ultimate 20. Then at least you could get the maximum out of the lever.

    Reduced sail area or a bendy mast top could also help solve the capsizing issue but thats another direction...

    Good luck and fair winds.
     
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  9. bananabobs

    bananabobs New Member

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    That's the key, improving your sailing skills will always give returns and IMHO it is one of the reasons I sail. Others try to improve their golf game, I sail.
    The boat was designed with that amount of sail and that much ballast. I for one will not play; "Are you smarter than an Architect?"

    I am willing to bet that you have been knocked down on Westlake...did it happen when you came out from the lee of some houses? I know it is very gusty on Westlake and the structures make it even more so.

    I would NOT recommend a different design! I love these boats too. If they are too much for someone, then those electric boats on Westlake are more their speed.

    I cannot stress enough...hand hold your main sheet. DO NOT lock it down. One hand on the tiller, on on the main sheet. You will not get knocked down and you will "Feel" the boat much better, if your main is cleated, you won't or can't respond fast enough when the wind shifts or gusts.

    The foam in the mast and the foam sail panel will keep it from going completely over so by all means however, altering the boat with added weight will not keep the boat upright if proper handling is not followed. These boats are not tippy...they are fast, maneuverable, hot rods and must be handled accordingly. You can drive a Porsche slow and mild, just stay off the gas, but why?
     
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  10. Solarfry

    Solarfry Member

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    C14 Centerboard weight.

    You can place a 20# bulb at bottom of keel or you can make a new centerboard using a piece of cut sheet steel weighing no more than 40 # without messing up your boat.

    I made a new centerboard with a piece of 1/8 x 3' sheet steel wrapped in plywood, fiberglassed and shaped like an airfoil. It made the sailboat way more stable and did not damage the trunk.

    I purchased the steel and had it cut at a metals supply shop, used exterior grade wood and plywood. Faired it into an airfoil, Then fiberglassed the whole thing. Spent about $80.00 total. If you use narrower pieces of ply and build the foil you can use bondo to make the edges foil like. Sanding does the rest. Not hard to do. Well worth the effort since I sail in forecasted 15 to 25 most of the time
     
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  11. ross ellena

    ross ellena Member

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    Centerboard

    Thanks Solarfly !
    This is more what I was thinking.
    The idea is NOT to make the dingy into a keelboat or event to make it "capsize proof" but just add a little more stability for single handing in gnarly winds.
    Ross
     
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  12. bananabobs

    bananabobs New Member

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    What is the increase in weight? Do you think the new CB is stiffer than the original? What do the rules say about racing with a weighted CB?
     
  13. Solarfry

    Solarfry Member

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    Weighty Centerboard

    I have no idea what the class would say. I bet they would like you to use the original centerboard in any sponsored races.

    The steel cored centerboard adds about 40 to 45# # to the weight of the boat. I ended up with a 65# centerboard. A lil weighty to lift with one hand but worth the effort as it really stiffens the boat up. It takes a lot more wind to heel it so you can carry full sails longer.

    Makes it a lot safer and enjoyable when you are taking the spouse and/or children sailing.
    (Some spouses and children fear boat heel) I still have original CB for boat. In case I sell boat, but I feel no need to re-install it. A friend tried it and wants to buy it.. I'm waiting for the right amount of $$ and he can have it. I've got my eye out for an American Sail 14.6 for sale two blocks away. I has a bit larger cockpit.


    Best SF

    PS It took a bit of work (1 to 2 hrs per side) to get it faired perfectly and looking like a foil. The most time spent was going back and forth to Home depot to get the slim pieces of wood, plywood, fiberglass cloth, fiberglass, catalyst and to West Marine for the gel coat to paint it with. Looked really good when finished. I devoted 3 half days to it. and a couple of days per side to let the fiberglass and gel coat dry completely. All in all a 7 to 8 half day project.
     
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  14. fan

    fan Member

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    Regarding racing the boat with a wieghted cb, you wouldn't be following the class rules so no class racing for your boat. In a non one design race , you'd let the governing race authority know so they could adjust your rating number accordingly.

    I get the impression that most of these sailors weightings the cbs are non-racer, day sailors just wanting to make the boat more enjoyable for their lives on the water. I say good for them for overcoming a tiippy (to them) boat and continuing to sail the fun little C14. I'm not going to encourage people that sail to jump to electric boats but instead to sail within your limitations.

    This isn't about staying off the gas in a Porsche , its about enjoying a Porsche at speeds they are comfortable with.
     
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  15. Solarfry

    Solarfry Member

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    Weighted Centerboard

    Well I sold the c14 to my daughter and went and purchased an American Sail 14.6. I am very pleased with it as I no longer race. It has a factory weighted centerboard and appears much more stable than the C14.2.

    We took it out in 18knt winds and got it up on plane downwind with board up. GPS indicated 14 mph for a short run. We managed not to flip her! Reaching she is very well balanced and does not tend to head up into the wind but continues where you point her while your behind is hanging over side and over water.

    It appears to be a lil bit bigger than the C14 and the mast is stepped inside the cockpit. Weight runs 450# and we pusher her with a minn kotat Riptide 40. Under electric power she clocks 4.4 knots. Which manages to push it against the tide at 2.2 knots. I might need an 4hp outboard to get her in and out the inlet. The 3.5 has a tiny tank and ran out of fuel quickly. The 4 has a 3gal tank.

    Will keep in touch.
     
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  16. JGM

    JGM Member

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    Just my two cents, but I would be very leery of laminating plywood to such a large piece of metal. Metal has a temperature sensitive coefficient of expansion - the warmer it is, the larger it is.

    Plywood, on the other hand, doesn't respond much to changes in temperature and instead changes more with moisture content. You might get away with such an assembly in someplace like California where the temp fluxes aren't extreme, but where I live with cold winters and blistering summers, the potential for failure would make such an option very dicey, IMHO.

    Now, if you leave the plywood out, that's another story. Plastics expand and contract with temperature much to the same degree as metals. Or you could glue on short, narrow pieces of wood, leaving space around each piece and filling that with something flexible before laminating with fiberglass.

    Personally, I would opt for reefing the mainsail and/or installing a jib furler for single-handing during heavy winds. The C-14 sails pretty well with reduced sail area, and unlike adding large amounts of weight for stability, this option is easily reversible.

    Hope this helps,
    Jim
     
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  17. Solarfry

    Solarfry Member

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    I am sorry to disappoint you. I never had a problem with that Weighted centerboard and it was often left in water for several days. In 8 yrs. it never delaminated or expanded or did any of the scientific things you claim. It is still in like new condition. The centerboard is not out in the sun so it does not heat up enough to be any kind of a problem. I am in CA and sometimes I spend months in FL. So extremes of heat and cold had not effect to date.

    I would propose you build one and test your hypothesis of expansion on it.
     
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  18. Solarfry

    Solarfry Member

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    Perhaps it may have been because I never gave it a scientific thought.

    Sometimes, Ignorance can be bliss..

    :D
     
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  19. JGM

    JGM Member

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    I didn't mean to ruffle your feathers - only offer my expertise in improving the design. I've been a custom home builder and furniture maker for the last 39 years and I've seen two previous instances where these metal/plywood sandwiches have failed. I'm not saying yours didn't work - obviously it did. I'm just saying there are better ways and I would hate to see someone spend all that time to build something that doesn't last.

    Are we OK now? ;)
     
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  20. Solarfry

    Solarfry Member

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    No ruffles..

    Pretty hard to ruffle my feathers. I don't have any. Mess my hair might be possible but I'm losing that.

    Putting things to work always takes some care and determination. I tend to overbuild. I meant that cb to last forever as I truly hate things that don't work. It is a lot more time consuming to build up the shape in bondo or other plastic. You have to establish a lamination schedule and then lay-up the glass over a certain time frame or the bondo will not stick to each other chemically. Foam is an option but then you need specific glues and it can get crushed by the steel. You can also use vynil sheets but I did not have ready access.

    I used epoxy to glue the stuff together. Epoxy is not hydrophilic as much as fiberglass and transmit temperature changes evenly across the material so enclosed. Epoxy costs a bit more but accelerates project in time by over a week. Time I cannot buy nor borrow. I am time sensitive. Heat is not a problem as the cb is never in the sun so it will not heat up more than the surrounding area. Temperature is not much of an issue as the temps drop gradually over a period of time. I am sure should you expose the cb to weather and sun it will fail. So far it has not seen a temperature change of more than 80 degrees over a 24 hour period.

    I am familiar with the problems of heat, heat transfer and heat caused expansion as I installed commercial Air conditioners in building and factories for 6 yrs with Honewell.

    No problem on my part.

    Hope all is well and you see fair winds and fair skies.

    best

    sfr
     
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