I haven't sailed a Dory, but in my experience with other boats with wooden daggerboards the problem has always been keeping the board down, not up. Wood being what it is (wood), the boards always try to float up and out of the daggerwell. The deeper the board is in the water, the harder it pushes up. A piece of shock cord across the top counteracts this such that the higher the board is out of the water, the harder the cord pushes down. By adjusting the tension you can get the forces to balance and set pretty much any height you want for the board.

If you want to pin it, though, I wouldn't use the pins you linked to. Since they're narrow and very much harder than the wood they'll concentrate the weight and gouge into the wood on the daggerwell. They'll also concentrate the force in the daggerboard hole and wear it out of round.

I'd use homemade pins made of big fat dowels, maybe inch and a quarter in diameter. The generous surface area will spread out the force and being wood it is closer to the same hardness as the boat's structure than stainless steel.

Have fun,

Laszlo

   Some dagger boards have a sprung brass strip that would provide a friction fit to the trunk to either hold the dagger board down or up or any place in between as needed.

One of several reasons for the sharp rake in the Northeaster Dory's daggerboard is that the tendency for the wooden board to float up creates a sort of "cam" action in the daggerboard slot.  So it's less apt to float up than a vertical daggerboard.  I dislike pins for holding boards either up or down;  it's a hole where water can get in.  A loop of bungie cord around the daggerboard to press it against the trunk is my preferred scheme.

To hold my daggerboard down on my dory, i just took a polyester webbing strap that has a quick release adjustable buckle (like a sleeping bag tie-on strap that you get at REI), cut it to length, and fastened each of the two ends to the sides of the daggerboard trunk with finish washers and short screws.  Holds the daggerboard down securely, and also holds on a trunk cap that i made for when the daggerboard is not in use.  I think that's a better solution than a pin. 

BTW the trunk cap is essential.  When you're rowing, if there are waves, if you dont have one, you will get water coming in through the top of the trunk.   Plus it makes a lot of noise!  I havent tested a capsize yet, but I suspect that being able to cap off the trunk may also be critical for being able to bail out a swamped boat.

   There is a reason why dagger boards and center boards are not usually pinned or tied down.

What would happen if one did not raise the dagger board or center board before entering very shallow water?

Bungee cord will strech so the dagger board/center board will rise up and over any obstical under the boat.

A friction sping would allow the board to rais up but would not pull it back down.

"Bungee cord will strech so the dagger board/center board will rise up and over any obstical under the boat."

No. Not one daggerboard I have ever sailed with has raised itself up and over any underwater obstacle, and daggerboard boats have been my thing for several decades. When you enter shallow or obstacle strewn waters you just need to slow way down and be ready to manually raise the board. A bungee cord arranged to hold the board in place by only creating increased friction between the board and the trunk will let you quickly raise and lower it, and will hold it any position that you like.

Old Yeller.   

Thanks all for the comments...talked me into not drilling holes and will use bungee cord....could someone please describe how the bungee cord is attached? (and where?)

Thanks

Curt 830/997-8120 [email protected]   

I'm not familiar with the exact setup on a NE Dory, but here's a nice compact system that never gets in the way:

Get a piece of clear vinyl tubing just slightly longer than the slot in your daggerboard trunk, and has a large enough inside diameter to thread you bungee through. Fasten the two ends of the bungee through small eye straps on the same athwartships SIDE of the slot, but near opposite ENDS of the slot. To use, pull the tubing sideways past the opposite side of the slot, and insert the board. The bungee exerts a side force on the daggerboard that creates friction against the inside of the trunk. Stopper knots can be used on the ends of the bungee where they pass through the small eye straps, and tension can be adjusted by fiddling with the location of those knots.

Another common system is to drill a hole through the front top corner of your board just large enough for the end of a bungee to go through. Attach a hook to the other end of the bungee and hook that end to something up near the mast after the board has been inserted in the slot. The main downside of that rig is that it gets in the way of any forward cockpit occupants. It does do the job of keeping the board where you want it, though.

If you don't like either of those ideas, just use your ingenuity ...

Old Yeller 

   I had a sailing surfboard, Boy's Life, and the dagger board woul float up so I added a brass spring strap to provide enough friction to keep the dagger board down. For some beaches, the dagger board would slide up.

Thanks for all the comments!  I appreciate them and will put them to use.