daggerboard or centerboard design

[Murray92589]

i just got this sailboat and it has no dagger board and i have no idea where to start. i know that it has to be a certain percent of the sail area, but i've read 2 or 3 different percents... also is it possible to build my own by sticking a couple pieces of plywood together and then making a rounded edge? (as pictured) and then using some paint and sealant on it. another consideration is if the dagger board should have a rounded or squared bottom edge?

i will post my sail measurements if you want but it'll have to wait till tomorrow because its dark out now.

if anyone has some links to daggerboard or centerboard design please post them, anything will help me.

this is how i want to build it if its possible. by gluing several boards together and then rounding them out at the leading edge.

here is the boat, i have no idea who made it or what type it is. it is 14 ft long

 

[flyer4ever]

Re: daggerboard or centerboard design

I had a boat very simular to yours. The dimentions will be the thickness of the daggerboard opening and the width will be 1/2 in narrower than the opening so as not to bind. My daggerboard was made out of 3/4 in plywood ,one piece. The board hung below the bottom approx 30 inches. Start there with a wooden cleat on each side as a stop to prevent the board from dropping through. Try the boat in mod wind. You can raise the board up to ajust it . When you find the most comfortable place according to your sailing ability,mark it and ajust your cleats there. Hope this is helpful. Ernie.

 

[Murray92589]

Re: daggerboard or centerboard design

you had a single sheet of plywood? was that sturdy enough? i would think it would need a little more reinforcement, but i really have no idea what kind of stresses are put on a dagger board..

 

[jspano]

Re: daggerboard or centerboard design

i seen this on the topic
"For a dinghy of your size I'd make the dagger board two feet or so long, with the lower end in a semicircle so it does not matter which way you put it in. It should be eight to ten inches wide. Five eighths ply will do - threee quarters is better - exterior grade is fine for this job. Remember to West the edges - ideally epoxy and glass the whole board for a Rolls-Royce job.
"
http://www.ybw.com/forums/showthread.php?t=198470​

 

[andgott]

Re: daggerboard or centerboard design

You can get away with an all-plywood board- You want it to slide easily in and out of the slot, not too tight.

Better yet, make one out of fiberglass- You can start with a wood core, then build a few layers of glass and epoxy on to it, it'll be sturdier that way!

There are a LOT of production boats in that general size range that you can copy the board from.

 

[Murray92589]

Re: daggerboard or centerboard design

thanks for the advice so far. i would not have a clue where to start with fiberglassing something, but if i can do a simple piece of plywood this shouldn't be as hard as i thought. about how deep should the board stick out below the boat?

 

[Murray92589]

Re: daggerboard or centerboard design

I've started a new thread for the remainder of my project. Update: I've staarted putting the varnish on my daggerboard. http://forums.iboats.com/showthread.php?p=2504156#post2504156