Aftermarket daggerboard?

Thorpydo

New Member
Hey Guys,

I'm working on an idea that I have for the keel or daggerboard of a sailboat. The premise is a daggerboard that the user can control to provide more or less righting moment. I've done some research and the closest thing that I have come to a similar concept is the swing keel. The swing keel accomplishes the same thing that this would but in an entirely different manner. My idea doesn't require ballast so it seems well suited for a laser and I suspect that is the boat I will use for the proof of concept, hence, my posting here.

I've been wondering what I'm going to do after that and am curious about the marketability of an aftermarket daggerboard for the laser. I understand that the daggerboard wouldn't be legal for the laser class regattas. Would there still be an interest? Is there an open class regatta? Would people be interested in it for day sailing? What's the percentage of sailors, racing to recreational?

I talked with a local shop owner who was asking 300 something dollars for a laser daggerboard. Do they typically cost this much? Is there a another boat that I should be looking into instead?

Thanks for your time and advice,
Adam
 
As I understand it, the purpose of a canting (swing) keel is to move the ballast to windward, thereby creating righting moment even when the boat is sailing flat. Most canting keel sailboats have additional foils for increasing lateral resistance lost when the keel cants.

If the Laser dagger board you propose cants to windward but has no ballast I'm pretty sure the only thing you will achieve is loss of lateral resistance, making the leg to windward a very long one.

Aside from the engineering challenges you face, if you were able to produce a canting keel with ballast for the Laser that would work, but would fall well outside the class rules and would not be legal. Could be a lot of fun though with an 8.1 rig on reaches....

Good luck :)
 
I am far from an expert here, but I see a couple of problems with your concept. First, as already pointed out it wouldn't be class legal. So, it would apparently only have appeal to rec sailors. Would there not be modifications necessary to the hull and cocpit? I think that the cockpit is pretty small now and that would be one more impediment to deal with. The expense of the mods to the hull and all would probably put most Laser rec sailors off. I don't want to sound discouraging, but I would think a boat with a larger mix of rec vs. race users may be a better choice for this endeavor.

Good luck in whatever you decide. If you decide to go with the Laser, keep us posted.

Mike
 
dont waste your time. there would need to be lots of hull modifications needed to make it work. you would lose the ability to pull up the board. with lasers if your not heavy enoufgh you can get a smaller rig. because you would lose the ability to pull out the board you would then lose the ability to beach the boat which i think is a good point for rec sailors. there is a good reason why lasers were designed the way they were. if you want to try this look at boats like cl14's or along those lines. but on lasers i think this is a idea that is better off dieing a quick death
 
The above comments make various assumptions. You need to tell us more. You say it has no ballast. Good, that covers the 'a boat has four ends concept'. Will it fit the Laser hull without modifications? Tell us more!

PS There ain't nothin new in sailing.
 
Zoophyte:
As I understand it, the purpose of a canting (swing) keel is to move the ballast to windward, thereby creating righting moment even when the boat is sailing flat. Most canting keel sailboats have additional foils for increasing lateral resistance lost when the keel cants.

If the Laser dagger board you propose cants to windward but has no ballast I'm pretty sure the only thing you will achieve is loss of lateral resistance, making the leg to windward a very long one.

Aside from the engineering challenges you face, if you were able to produce a canting keel with ballast for the Laser that would work, but would fall well outside the class rules and would not be legal. Could be a lot of fun though with an 8.1 rig on reaches....
You understand the canting keel as I do. We're on the same page.

This keel does not create a righting moment with ballast and the keel does not cant. I'm more interested in the viaibility of a keel like this rather then the engineering or design behind it.

And I guess that means there isn't an 'open' class. Shucks. Are their open classes for other small boats like this?

As gordo strangler and mikescott asked about a modification:

No modification to the hull would be required. You could but this daggerboard in your laser for half the day and later on switch back to the stock one. This is the number one reason I chose a laser in the first place. I don't own a boat though I have been taking classes or renting them for day sailing the last three years or so. No modification required means I don't have to purchase a boat to get a proof of concept going. It slides into the slot just like the stock one does.

gordo:
dont waste your time. there would need to be lots of hull modifications needed to make it work. you would lose the ability to pull up the board. with lasers if your not heavy enoufgh you can get a smaller rig. because you would lose the ability to pull out the board you would then lose the ability to beach the boat which i think is a good point for rec sailors. there is a good reason why lasers were designed the way they were. if you want to try this look at boats like cl14's or along those lines. but on lasers i think this is a idea that is better off dieing a quick death
You can pull the daggerboard up just like you can with the stock daggerboard. If everyone had an attitude like yours we wouldn't get very far as the human race. Dream a little :). I will look into the cl14's but can you please explain your reasoning behind this boat versus others?

Strangler:
The above comments make various assumptions. You need to tell us more. You say it has no ballast. Good, that covers the 'a boat has four ends concept'. Will it fit the Laser hull without modifications? Tell us more!
I guess I mispoke. The daggerboard will weigh something but it will most likely be less then the stock.

Since I'm already going to be making a couple daggerboards, I thought I'd look into it a bit and see if this in itself is a viable product.

Steer me clear if people aren't interested in a product like this but please resist the urge to attack a design in which you haven't seen.

Ahh, and what percentage of rec vs. race would you guys estimate?
 
Steer me clear if people aren't interested in a product like this but please resist the urge to attack a design in which you haven't seen.

Ahh, and what percentage of rec vs. race would you guys estimate?

The hostility with which you have been met is due to the nature of the Laser class, I suppose. It is very closed to change because of the one design concept. That does not mean that there isn't change, but you really have to jump through hoops to get something approved by the class. On the other hand, there are plenty of recreational sailors who may have an interest,* and there is even a larger non-approved sailing rig, the 8.1, that is being picked up by heavier sailors.

*I don't know, since I don't understand what you guys are talking about with this centerboard.
 
Interesting technical concept, but I will comment this. The only people willing to spend money on their Lasers are racers. If it isn't class legal, you can't race with it. I really don't see a market for something like this, at least with a Laser.
 
Have to agree with torrid. But by all means, keep working on your design if you find it fun. And find a class of sailboats where your concept would be class legal from the get go.
 
my views as to why the cl boats would be a better fit for this is because they are cottage boats. i there there wold be much more of a market ( more then none) if it was built for these boats. would the keel be a solid piece or have a bulb with the weight. you also need to look up if the hull would be able to withstand the extra weight that would be needed to have a keel. i do not see a way for the hull to not need modifications. if it were a canting keel then you are in more problems because you can not just insert it into the trunk. it would have to be installed from the underside of the boat. also the factors of generating lift would change with a different foil. that could very easily change how the boat handles. back on the sliding out the dagerboard idea, how heavy do you plan on making it. people might not want to struggle to get a significant amount of weight in whenever they go sailing
 
Seeing as you asked so nicely I'm trying to resist the urge to attack your unspecified design, but do you really think you've come up with something that no-one has ever thought of before? That's hard to believe. For such a daggerboard to work, you'd have to be rewriting some of the most fundamental laws of physics. Unless you are talking about adding wings to the daggerboard or something like that. Nothing new there.

Moths are probably the front line of small boat development so I'd recommend looking for some Mothies to talk to if you honestly think that you've come up with something new. Don't expect a positive response though - they'll be much more sceptical than anyone you'll find on this forum and much less polite. I'd suggest the Sailing Anarchy forum, but I'd be worried you wouldn't come out of there alive.

Even if your idea is good, don't expect to find a market for it. By and large, the development classes run on love, not money.
 
this idea would not survive at all on sailing anarchy. if you go more into depth with this the end result have time and money both gone on your part without it coming back. alot of people if they want something that wont tip and for rec sailing with the fam then they will look at smaller keelboats and daysailors
 
I'm still intrigued by this daggerboard. It will provide more righting moment than the stock one, but it may actually weigh less. You can easily exchange it from the deck side. Are we being punked?

I can see a market for this magic centerboard, if reasonably priced, for making the boat more stable for sailing education programs. Got several old Lasers at the club, and you have to put two beginning sailors on them to hold them down.
 
I'm a rec sailor, But keep my boat legal.... torrid made the point, the only folks spending sums of money on these boats are racing sailors.... While that is more of a guideline than a rule, I think it's a guideline most tend to follow.

Case in point, as you know the "pro" rigging for the laser that replaces the vang, outhaul and cunningham has been available for years. Yet, I only have the pro rig on one of my two boats. as a recreational sailor, I cant justify the expense of same.

There is a reason laser parts are so expensive, namely that there is a small number of 'blessed' builders and a large number of people who wish to keep it that way.

If your goals are to build a cool daggerboard that allows you to enjoy the thought and experimentation of doing same, go for it, it sounds great. If your goal is to make money at doing so, pick another boat.
 
I 14's are a progressive class so any improvements to the boat are usually adopted. The laser is a strict one design so here are my thoughts. The class more than likely would resist it. Rec sailers just want to sail so I would be suprised if you sell more than five to the rec demographic.

I would be interested in what improvements could be found. The laser is a good choice due to the amount of them out there but like I stated getting the class to avceptnit would be the only way to make it profitable.
 
Personally, I don't think there will be any benefit from the concept. The weight of the centreboard is so minimal that to swing it, would not impact on the centre of balance of the boat.

If you really want to experiment, I'd suggest looking closely at the Moth Class and specifically the foilers, where the boat is lifted clear of the water by a hydrofoil on the tip of the centreboard. However, I suspect the weight and speed of the laser would require a very big hydrofoil and this would create to much drag for the hull to lift clear of the make the water.

Further, if you're really into experimenting with designs, I suggest hopping into a class that encourages development, rather than a strict one design class. The strength of the laser class comes from being a strict one design class, so the people that sail them are going to resist changes that make them less of a one design class. Also note that any fitting you add to the hull to make it work, would need to be removed before the boat could be raced.
 
Oh more incorrect assumptions!

THORPYDO SAID 'This keel does not create a righting moment with ballast and the keel does not cant.'

So whats the idea? Ventilation holes? Gybing? Movable trailing edge? Flip out wings?

Most class rules say 'no moving parts'. [As I said before, there aint nothing new in sailing. The idea of canting keels was around in the late 1800s.]
 
How much lead would you need to add to a Laser centreboard to give the boat the righting ability of one of the 'sailability' classes (disabled sailing classes)??
 
How much lead would you need to add to a Laser centreboard to give the boat the righting ability of one of the 'sailability' classes (disabled sailing classes)??

Keep in mind that those boats are designed to self-right with a person strapped into the cockpit (working *against* the righting moment), while the laser is designed to be righted by a person who has left the cockpit and instead has swum around to the daggerboard, and is now applying her weight only to righting.

In other words, it's more than twice as hard to for a boat to be self-righting.

You don't mention lengthening the daggerboard to create additional leverage, so let's assume keeping the same length.

So I'd SWAG that if your helmperson weighs 150lb, you could make the laser "self righting" by adding "only" a 300lb shoe to the bottom of the daggerboard. Think that'll change how the boat sails much?

Really, the laser hull is a *very* poor starting point for this application - you'd prefer a hull design with considerably more initial stability and reserve bouyancy for a self-righting application.
 
there would be other issues with turning a laser into a boat for disabled sailors such as steering. the 2.4meters have the ability to be used with a joystick system and also a suck/puff system. any of the ideas here about the additions to the laser are quite useless imo. there are already classes that incorporate the ideas and trying to turn a laser into something that could do similar would not be a good investment in design anyways
 
Hi guyz i think what should be made is la laser daggerboard that is weighted so it help with the righting movemont of the person sailing that way you could use the more powerful rig on a windier day although this would not be class legal. unless you could make it look as close to a laser one as possible. i think it should maybe have a screw in bung/stopper so the ballast could be altered by adding led shot to increase and taking some out to decrease, using this method you could use almost a standard board but hollow although it would need to be reinforced.
 
I have to ask why should the boat be altered all the time to make it easier for light people to sail the boat in heavier winds, when already there are two smaller rigs available? It's not as though the heavier people can alter the boat to make them more competive in lighter conditions. Sail the rig that suits your body weight the widest range of conditions and suffer accordingly in the conditions that don't suit your body weight.
 
Hi guyz i think what should be made is la laser daggerboard that is weighted so it help with the righting movemont of the person sailing that way you could use the more powerful rig on a windier day although this would not be class legal. unless you could make it look as close to a laser one as possible. i think it should maybe have a screw in bung/stopper so the ballast could be altered by adding led shot to increase and taking some out to decrease, using this method you could use almost a standard board but hollow although it would need to be reinforced.

Try it out. Report back to us on how it works out for you.

We don't learn much from people on BBs telling us - we really learn by engaging, experimenting, building, failing, retrying, succeeding. In that spirit, I encourage you to try out your own ideas.

The only point of concern is your quote "although this would not be class legal. unless you could make it look as close to a laser one as possible." How things LOOK is not what makes them legal. There's an ugly name for those who don't follow the rules of the game and then camouflage appearances to avoid detection. Don't be one of them.
 
It's no joke (please, do not confound it with the Aprils-Fools-Joke, that several years ago I made at TLF ), but:
About 3 to 4 years ago, someone at ebay.de, offered a Laser Standard (for recreational sailing) with a simple selfmade "heavy stiff keel"-centerboard.
It nothing has to do with a canting keel /swing-keel. Unfortunatley I not made a copy of the ebay-photo, sorry.
This "keel" probably was made out of a stainles steel plate, that has the same shape like the common centerboard for the Laser.
At the lower edge, it had a sufficient weight in same shape like a "keel-bomb" for a yacht (of course in higher scale / suitable for the Laser). Perhaps that weight was out of an iron-alloy, I can't remember.
If I remember correct, the upper edge had a plate that was fixed to the centerboard-blade aft the blade was put in to the centerboard trunk from the waterside of the hull. So, this "selfmade 'heavy stiff keel'-centerboard" couldn't fall out, during the sailing. There was, I guess, a hole through the blade to fix it temporary with a pin/pole into a position, to pull up that complete blade into a position "up" for slipping.

The Laserite that did offer that Laser at ebay.de wrote, he not did want to quit lasersailing but had medical reasons to design and construct such a "heavy stiff keel"-centerboard. With that construction he could sail on his loved Laser, although with a common centerboard, he wouldn't be able to sail Laser. He wrote, the Laser wasn't to slow, but the heeling was very low in stronger winds.

For recreational sailing the Laser only, the classrules and "legality to the class rules" not is a religion / bible to follow always 100%. Some few a bit fanatic active Laserites perhaps do not have an understandig for this "lazy opinion" to the class rules , I'm afraid. ;)

Ciao
LooserLu
 

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