Building a new Daggerboard

Thread starter #1
Hey guys. I am working on getting my new Sunfish Clone (Lockely Newport Scat or Gloucester Yachts Sun Dolphin) back on the water and one thing that has to be completely replaced is the daggerboard. It's warped beyond repair. I know I can go the marine plywood and varnish route, but just wondering if i could make one out of King Starboard that would never rot.

Thoughts? It that stuff strong enough to do the job?

Thanks,

Kevin
 

beldar boathead

Well-Known Member
#2
Based on their description, it sounds more for decorative/trim than structural use:
  • Environmentally stabilized - withstands the harshest marine conditions
  • Won't rot or discolor like teak and other solid woods
  • Won't delaminate like wood laminates
  • Easy to work with using standard woodworking tools
  • Matte finish on both sides to hide scuffs and scratches
While it might be ok to sail in light air, in heavy air it seems like it would twist or bend. You are not racing, so maybe that would be OK, but if you capsize, is it going to support your weight hanging on it to right the boat, or will it snap?


I don't want to get sued if something bad happens to you using any of my comments above, so I want to point out I have no expertise whatsoever in the use or wiseness of any material for any nautical or other purpose.
 
Thread starter #3
I know what you mean about it needing to be strong enough to hang on. I have a 20' sportboat that has a lifting centerboard and when I've flipped it that centerboard gets a decent amount of force on it to help right the boat.

So it sounds like plywood is the way to go then?


Based on their description, it sounds more for decorative/trim than structural use:
  • Environmentally stabilized - withstands the harshest marine conditions
  • Won't rot or discolor like teak and other solid woods
  • Won't delaminate like wood laminates
  • Easy to work with using standard woodworking tools
  • Matte finish on both sides to hide scuffs and scratches
While it might be ok to sail in light air, in heavy air it seems like it would twist or bend. You are not racing, so maybe that would be OK, but if you capsize, is it going to support your weight hanging on it to right the boat, or will it snap?


I don't want to get sued if something bad happens to you using any of my comments above, so I want to point out I have no expertise whatsoever in the use or wiseness of any material for any nautical or other purpose.
 

Webfoot1

Active Member
#4
Go to your Big Box and get a White Oak board. When you're done
you'll have something nice and as good as what came from the factory.
Actually better if you give it some type of airfoil shape. I've had Sunfish
where someone made a plywood board, I chuck them in the trash and
make a new one from white oak. After many many coast of Spar Varnish I have
something that will last longer then me. It's hard to beat a material that's
been the choice of boat builders for centuries.
 

L&VW

Well-Known Member
#5
:eek: Don't chuck those plywood boards—yet—without gluing a wide strip of coarse sandpaper to them to "clearance" daggerboard trunks.

While nearly unbreakable, marine plywood may bend too much for such uses. I've got two plywood leeboards that I used to pick up some speed to windward on my sailing Folbot kayak. I could cut them narrower for Sunfish use; however, it may be [more] difficult to move a plywood board while there is a lateral force acting on it. Leeboards don't have that raising/lowering issue, but they can be seen to bend. :(

It's hard to beat a newly-varnished finish on a Mahogany board :cool: but agree that White Oak is good for strength and longevity. Remember to tether the board to the boat. :rolleyes:

BTW: Lowes and Home Depot offer a 10% Veterans discount, but the availability varies by region and store. Be prepared to bring with you a military ID, Honorable Discharge certificate, DD214—and, if applicable, a Disability Card. Lowes can tie it with their membership card—to be used instead of other identifications. Some HD stores honor their offer only on certain Holidays. :confused:

.
 
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signal charlie

Well-Known Member
Staff member
#6
Congratulations on your boat.

I'd want to know if Starboard floats or delaminates. You might call Jamestown Distributors and chat with their Tech Team about it. Whatever you make the daggerboard out of, you'll want it to float. Cypress will. I know teak won't.

Is the board close in size to a Sunfish board? Maybe one would fit without trimming or it would be good wood to use for the Sun Dolphin?

Cheers
Kent
 

mixmkr

Active Member
#7
For what it's worth, I use Starboard, Marine lumber...whatever you want to call it, quite a bit. However, for a piece as thick and as big as a daggerboard, you're approaching the price of just buying a new one from Intensity, if class legal isn't important. That board is a great substitute or replacement. If you value your time, that is by far the best route. Also, the starboard will flex too much, being that long. It won't warp or come apart, but really isn't the right material as well. What you CAN do is glass over some wood or even "bury" some reinforcement rods if you think a piece of wood will flex too much. The suggested woods above should be fine. Lastly...as far as floating, that is desirable, but not a necessity, if the board is secured to the hull with a tether, etc. The fear is it getting away from the boat and sinking to the bottom. My leaky masts will do that too!...eventually.
 
Thread starter #9
That intensity board is nice and for $175 bucks is definitely worth it. If I bought a sheet of marine plywood and invested in epoxy resin i'd be out at least that.

I'm not sure that board will work though. It looks to go straight down while I think my daggerboard trunk is tilted back. I'll take a picture and see.


For what it's worth, I use Starboard, Marine lumber...whatever you want to call it, quite a bit. However, for a piece as thick and as big as a daggerboard, you're approaching the price of just buying a new one from Intensity, if class legal isn't important. That board is a great substitute or replacement. If you value your time, that is by far the best route. Also, the starboard will flex too much, being that long. It won't warp or come apart, but really isn't the right material as well. What you CAN do is glass over some wood or even "bury" some reinforcement rods if you think a piece of wood will flex too much. The suggested woods above should be fine. Lastly...as far as floating, that is desirable, but not a necessity, if the board is secured to the hull with a tether, etc. The fear is it getting away from the boat and sinking to the bottom. My leaky masts will do that too!...eventually.
btw...I extended a daggerboard (two times, as you can see in the first picture) using various methods...don't waste your time. The Intensity board is MUCH better all around, mainly due to the aerodynamics of the board.
 
Thread starter #10
If you check out this picture it seems to be canted aft. I would think that would mean the foil is all wrong relative to the flow of the water.


That intensity board is nice and for $175 bucks is definitely worth it. If I bought a sheet of marine plywood and invested in epoxy resin i'd be out at least that.

I'm not sure that board will work though. It looks to go straight down while I think my daggerboard trunk is tilted back. I'll take a picture and see.
 

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beldar boathead

Well-Known Member
#11
Well, if the slot is a similar dimension to a Sunfish board, it should not make a difference it is angled. It just means the foil shape of the Intensity board will be more elongated as the water flows over it than intended. I suspect the original board would be slab sided, so this board should work better, as Mixmstr pointed out in his experiments with long, slab sided boards vs. shorter foil shaped boards.

BTW, I have never seen another Conehead sailing, but in your pic you show two blockheads sailing, so at least I am not alone with a non-traditional noggin on the high seas!
 
Thread starter #12
Haha. I can't take credit for those blocks. I pulled that from the 2007 ad for a copy of my boat.

The old one was certainly a slab. Now that I think about the shape I guess it would be fine. I am not sure on the dimensions though about the trunk deth. Mine is 15 inches from deck to keel.

WHat are the dimensions of the Sunfish dagger?



Well, if the slot is a similar dimension to a Sunfish board, it should not make a difference it is angled. It just means the foil shape of the Intensity board will be more elongated as the water flows over it than intended. I suspect the original board would be slab sided, so this board should work better, as Mixmstr pointed out in his experiments with long, slab sided boards vs. shorter foil shaped boards.

BTW, I have never seen another Conehead sailing, but in your pic you show two blockheads sailing, so at least I am not alone with a non-traditional noggin on the high seas!
 

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andyatos

Active Member
#13
What are the dimensions of the Sunfish dagger?
I just measured my GRP Sunfish daggerboard. It's 9.5 inches from the leading edge to the trailing edge on the flat, non foil shaped section of the board that lives inside the daggerboard trunk when the board is fully inserted.

Next, the distance from the bottom of the rubber stop (that meets the deck) on my daggerboard to where the flat section of the board starts to transition to the foil shape is 13 1/4 inches. Which means that a standard foil shaped Sunfish daggerboard would fully project the foil shape of the leading edge and trailing edge of the board where it exits the daggerboard trunk even if the board is raked back on your boat.

As to the difference between a flat vs foil shaped daggerboard, if you can possibly Frankenstein a foil shaped GRP board to your boat, your really should. The amount of lift a foil shaped board produces in comparison to a flat sided daggerboard is significant. As in, you feel the difference the moment you switch to a foil shaped daggerboard from a flat one.

Cheers,

- Andy
 
Thread starter #14
I might be able to make that work. Is there a difference between the GRP boards and the ones that Intensity sells? I don't really plan to race this boat, but I do hate sailing slow. Wondering if a wood one might be stronger.


I just measured my GRP Sunfish daggerboard. It's 9.5 inches from the leading edge to the trailing edge on the flat, non foil shaped section of the board that lives inside the daggerboard trunk when the board is fully inserted.

Next, the distance from the bottom of the rubber stop (that meets the deck) on my daggerboard to where the flat section of the board starts to transition to the foil shape is 13 1/4 inches. Which means that a standard foil shaped Sunfish daggerboard would fully project the foil shape of the leading edge and trailing edge of the board where it exits the daggerboard trunk even if the board is raked back on your boat.

As to the difference between a flat vs foil shaped daggerboard, if you can possibly Frankenstein a foil shaped GRP board to your boat, your really should. The amount of lift a foil shaped board produces in comparison to a flat sided daggerboard is significant. As in, you feel the difference the moment you switch to a foil shaped daggerboard from a flat one.

Cheers,

- Andy
 
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mixmkr

Active Member
#18
Owning an Intensity glass board, it fits the slot in both my Sunfishes and looks to be well made....from someone who has spent over 30 years, professionally repairing sailboats. I made a transom hung rudder for a Pacific SeaCraft Flicka, and that took a bit. ...to the point sometimes it's just cheaper to buy one new if possible.
 

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