Skerry: Width of Daggerboard Opening

Hello ,

we are about to install the daggerboard trunk. Now the question is what width should the  daggerboard opening have respectively how much play should the daggerboard have? The daggerboard itself is about 12mm or approx. 1/2 inch. Would an add. 2mm on each side or overall give a good width?

I am also thinking if a reinforcement of the opening in the bottom panel with fiberglass would be a good idea or would that be overengineering?

Apreciate your help.

Thanks!

Reinhard 

 


12 replies:

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RE: Skerry: Width of Daggerboard Opening

I'm not qualified to answer your question, but I do want to point out that whoever answers it needs to know

whether you have applied epoxy to your daggerboard yet.  That can increase the thickness a bit--so I would

say you need to apply the epoxy and then use a good set of calipers to measure it in several spots.

I did not do this, just left the end pieces the size they already were after sanding.  This may have been a

mistake, because the daggerboard floats up every time I come about.  Wouldn't want it too tight, but a

little tighter might help.  Other than that I don't think it hurts for the daggerboard to tip slightly this way and

that.

I'm thinking of installing some kind of "fuzzy" weatherstriping similar to that used where car windows slide into

the doors.  If it's not too tight it wouldn't retard the movement of the daggerboard that much, but it might not

float up as easily or as often.  As of now I am using a bungee that just barely holds it down--not quite all the

way, maybe a half-inch up.  This is not ideal though--e.g., if I hit a sandbar the board does not slide up all the

way sometimes and that can't be a good thing.  If anybody has any thouights I'd sure like to hear them.

RE: Skerry: Width of Daggerboard Opening

A bit of extra width is good in the trunk so the board doesn't bind if it warps or swells a tiny bit. You can always tighten up the fit later by applying a lining of something thin inside the top and bottom openings of the slot. If you're going to fiberglass the board, get that done first so you can measure its final maximum thickness. I don't think adding 6 mm (3mm on each side) of extra side-to-side room for the board in the trunk would be too much. And that doesn't include any allowance for fiberglassing the inside of the trunk, if you do that (and I would). I would allow even more extra slot room in the fore-and-aft direction, if you can.

A simple loop of bungee cord is usually enough to gently hold the board down, or in a partially raised position. Experiment for some different ways of rigging it, so it doesn't get in the way when a crew member needs to move from one side of the boat to the other.

Does any of that help?

Old Yeller 

RE: Skerry: Width of Daggerboard Opening

By the way, Diving Duck, I've sailed with daggerboards for far longer than I care to admit, and have yet to have one slide up when it encountered an obstacle, including a gently sloping sandbar. You just have to partially raise them and proceed with caution when you get in shallow water. The tip of the board is going to get some wear, and if you hit something hard the thin trailing edge of the board will be damaged where it meets the bottom of the trunk. But none of those annoyances are difficult to repair.

Old Yeller 

RE: Skerry: Width of Daggerboard Opening

Yeller,

Thanks, and good to know.  I am definitely a novice--my first lesson was last September, then a few more this summer.  The little pond near my house has a lot of shallow areas that are hard to avoid and there is a high spot or two that I try to remember.  Anyway the daggerboard is getting a lot of abuse, but like you say easy to repair (so far anyway).  I'm got some slight damage to my rudder too when I forgot to release it.  There's bits of gravel here and there where I beach her.  But it's like they say, if you don't want your boat to get banged up, stay home.

RE: Skerry: Width of Daggerboard Opening

Hi Reinhard,

Please don't make your DB trunk to have anything near a tight fit for your DB.  It needs to be nice and sloppy so if your board warps or mud or gravel enters the trunk, things wont get buggered up.  And to keep the board where you want it, just tie one end of a length of shock cord to the mast and the other end to the handle of the board.  When  you tie the cord to the board, just snug things up enough to put the board into a fore and aft bind and tie a slipped overhand knot.  When you want to adjust the depth of the board, simply pull the board aft (against the tension of the shock cord) and raise or lower the board.  When you want to remove the board, just pull on the slipped knot and remove the board.  Bingo bango.  Works every time.  

RE: Skerry: Width of Daggerboard Opening

And here's an afterthought.  Of course my proposed shock cord arrangement wouldn't work too well if you have a passenger up forward.  I'm a singlehander and I think like a singlehander.  Passengers are barely tolerated on my boats or my motorcycles.  But, as Yeller mentioned, you can devise a looped shock cord arrangement beginning  at the forward end of the slot, extending around the trailing edge of the board and back to where you started with enough tension to hold the board where you want it.  You'll find that it's great fun to tinker around with your boat and her rig to get things just how you want them.  Enjoy, my friend.

John

RE: Skerry: Width of Daggerboard Opening

Hello All,

thanks a lot for all of your very usefull comments. Great help. Good arguments for not making it too tight. I will see about its tendency to slide up onces the boat finally gets into the water - this still will be sometime. Was just wondering if anything speaks against inserting the slot before glueing in the daggerboard trunk. In the manual it states it the other way round.

Thanks for your help!

 

Reinhard

RE: Skerry: Width of Daggerboard Opening

Reinhard, are you saying the manual suggests installing the trunk first, and then cutting the slot through the hull bottom later? And you want to do it in the reverse order? Why?

Old Yeller

 

RE: Skerry: Width of Daggerboard Opening

Hi,

It is mentioned after installing in the manual, but perhaps because it speaks of the rowing version first. So I will saw the opening before glueing the trunk in.

thanks for all of your help once more.

Reinhard

RE: Skerry: Width of Daggerboard Opening

Hi Reinhard.

Do you own a router?

John

RE: Skerry: Width of Daggerboard Opening

Hi John,

please excuse answering not sooner, I have been very busy finishiung our Skerry. We have now installed the seats, daggerboard trunk, mast step and -partner. It has been no problem to cut the daggerboard opening. I used a saw and a Japanese rasp.. I had been to afraid using my router -its a very cheap thing and not easy to handle.

Thanks for your help once more. 

All the best,

Reinhard

 

RE: Skerry: Width of Daggerboard Opening

Hi Reinhard,

Sounds like you've been busy.  Good for you.  We're all looking forward to seeing more pictures of your progress.  

John

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