Training, Pleasure and Racing Dinghy

How does a "more high end boat" carry less sail? High performance and large sail area go hand in hand.

 

I enjoy seeing good ideas come to life.What I'm trying to understand is what differentiates this design from a Laser Stratos or a Wayfarer,both of which have been carrying out the functions described for a long time.The we get to the range of training boats of all sizes from RS TEACH - RS Sailing, the world’s largest small-sailboat manufacturer https://www.rssailing.com/range/teach/ .The harsh reality is that an operator of a sail training centre will be concerned with the cost of purchase and the cost of operating and then,a bit reluctantly,the cost and availability of spares.The OP needs to ask himself what advantage it will give a training centre to buy from his putative operation rather than the builders I have listed.Because the man across the desk when a business proposition is being put forward will be asking himself this and it is rather important to have a good reason to give him.Putting forward a good business case as well as a sound boat will be essential,does the OP have boatbuilding experience,or is he planning to get another business to take care of production?

 

Concerning your hull lines as shown in a video of your website, they looks to be a good design but I recommend you to draw also the "deadrise" lines which are more adapted for a dinghy design to appreciate its expected planing mode :
>>> The standard representation with the waterlines at various heights is informative for the displacement mode at low speed but not much for the skimming mode on the water surface. The dynamic lift being a lot in relation with the deadrise angulation within each sections, I found useful to add the « deadrise » lines, i.e. the lines joining the points of the sections sharing the same local « deadrise » angle : 2°, 4°, 6°, etc...,20°.
>>> This representation, especially showing the shape of the central flatness (transversal angles < 2°) from the pointy bow to the aft transom, makes easier to guess how the planing mode can occur and progress.
>>> The attached document shows 2 examples of such representation with « deadrise » lines. And my preference goes for the example 1 with U-shaped sections, more exactly with "flat and shoulders" shape under the hard chine line on quasi all the length (except the pointy bow zone), instead of example 2 with regular rounded sections like it is for your current design : the deadrise lines have a very different look, and in my opinion the example 1 is better when aiming an early and faster planing mode.

 

Hi Dolfiman,

Thank you for taking the time to have a look at my stuff. I especially appreciate the helpful design advice. I understand the idea of connecting the points of equal deadrise angle and can see why its useful. I'm not sure - but I think it is the same as what the Flowlines function accomplishes in freeship because in the documentation it states that they are not generated by CFD. In any case I can post that here. They appear to run for the most part perfectly straight maybe you could comment on how that might affect it while it was in planning mode. When I towed the model it seemed to plane quite well and stayed on the plane for a very long time as I reduced speed. I ended up changing the design slightly after that because I felt like the aft sections were dragging a bit at low speeds, and on the advice of another designer with more considerable experience I reduced the volume in the forward sections currently the prismatic is about .573 whereas before it was about .58 . I also subsequently checked the waterlines at 10 degrees of rotation/heel and they are now nicely fair. I think the lines I work with now are a bit nicer than what I have on the site. Im planning to make another model soon for that.

 

Hi Wet feet,

Thanks for having a look. I was actually not aware of the Stratos, it seems quite similar to my boat. I fully appreciate your comment. Companies like Laser and RS make some great products, I especially like the RS feva. I do not have boat building experience, I would need to team up with someone. I do have some access to facilities and people with building experience.

I know the wayfarer has an excellent reputation as a easy to sail boat, but dont know much beyond that yet and ill have a closer look at it, are they still in production?
I never sailed a Stratos maybe they are great one thing at first glance is the stratos has a huge sail area, 160 square feet, a 470 has 135. The boats we use now are 16 footers with a sail area of 110 and a weighted centerboard. This is about all the power the people we have contact with seem to be able to handle. I wrote a long thing about SA/D ratio as it pertains to the level of athleticism required to sail a dinghy which is its own thing as long as you compare apples to apples. Because dinghies are stable due to crew movement as well as form the more SA you have on the boat the more the physical demands on the sailor because the crew has to make a lot of adjustments both for the gust and for the lull. The more sail area you have the more pronounced and exact these adjustments have to be otherwise the boat will not sail well. My idea was to keep the level of athleticism required to sail the boat relatively low, so I wanted a relatively light boat with a relatively low sail area and easily driven hull. I think that is a route not many of the big manufacturers have gone down for various reasons.
A self draining cockpit would also be quite important to my would be clients. I also personally prefer cockpits that are designed like that so I included it in the SOR.
Your post raised points I could really write forever on maybe ill revisit again and post later.

kind regards,
Loren

 

On checking,it seems that the centreboard version of the Laser Stratos is no longer being produced.There were two versions,one with a keel for extra stability more information here: Laser Stratos - Wikipedia https://en.wikipedia.org/wiki/Laser_Stratos .It seems the plan was to promote the Laser Bahia in the same market and there is a review of one here: The Bahia, An Affordable, Versatile Performance Dinghy https://www.sailingworld.com/sailboats/bahia-affordable-versatile-performance-dinghy/ . Their competitors at Topper offer the Omega,which is not dis-similar to the proposal that launched this thread https://toppersailboats.com/product/topaz-omega/ .Since I brought up the Wayfarer,it seems only right that I include a link to the builder so that price and specification can be compared Hartley Boats | New Sailing Dinghies https://www.hartleyboats.com/index.asp?p=newboats.

Given this number of boats on offer from established companies,it will take something with convincing attributes to make an impact in the marketplace.What unique qualities will the design have?Will a new entrant to the sector have the financial stability to provide a spares service in two years time?These are questions that will have to be answered and it is best to think of them in advance of an interview with a concerned bank manager.

 

Points well taken, thanks. I would say your arguments apply to everyone to some extent, including the big manufactures. Any designer can look at what is already there and say there is no reason to do anything else yet new boats come out all the time some stick around some disappear.

Im glad you mentioned the Omega actually it has a part in this story - I am not trying to publicly defame anyone's considerable efforts, but my impression of the Omega after testing it for years was that it has problems running from top to bottom and was comprehensively unsuitable. Most noticeably the cockpit floor is below the waterline which caused water to pool in the cockpit when loaded and could not be sucked out at low speeds. The huge 150 square foot sail area made the boat really difficult to sail in a breeze for anyone without the physique of Arnold Schwarzenegger. The boat was so tippy it was amazing yet at the same time so slow it was unimaginable - keep in mind not every product that comes out actually delivers what it promises across the board.

Anyways I'm not trying to set the world on fire here, I'm sorry if it came across like that if I could bring even one boat to life I think it would be time well spent.
regards

 

You illustrate perfectly the shortcomings of a similar design,ensuring that your design does not suffer from them will give you an immediate advantage.It would hardly be professional to specify which boat(s) you are taking as a baseline when talking with a potential buyer,but if you can demonstrate that you have taken steps to eliminate these sources of anxiety,you will have a strong selling point.I agree that there are new classes introduced in a steady stream,the varieties that have something new and desirable to offer will stand a chance of success.
Another factor to take into account is the cost of tooling;a rotomoulded hull can be turned out in minutes,but it' will require a very expensive mould and a very expensive machine to rotate and inject the polymer.A "traditional" GRP hull will take longer to laminate,but the tooling costs are lower.Either of these processes will require an amount of specialist knowledge applied to the project.Do you have a specialist in mind?

 

Hi Wet feet,

I have a specialist in mind, but I don't know how available he is to be honest. My plan now is to do a another model. I was also thinking of hiring someone for construction plans good enough to present to a builder. Actually there is someone on the thread I have in mind because I talked to him before in the early days. Maybe from that I could create some files for cutting the frames and panels ect because I would want to build it with foam and glass. From there I could start cutting things one by one and then later I could think about how to put it all together.

Loren

 

I was thinking high end in terms of not being a plastic boat.

 

I recommend that you go through a mental exercise to build and fit out the boat.It can be all too easy to need to locate a cleat over a compartment that has no access to the inside,making it hard to fit nuts on the end of the bolts that need to be there.The more detail you examine in your mind,the fewer problems will be hurtled into.

 

In that case, the maintenance cost of a wooden boat needs to be added to the comparison. It is a negative value. For most schools and clubs, finding a person to repair and maintain wooden boats may be unavailable or too expensive.

 

One of the problems today is that everybody wants what THEY want. By its nature a good school boat is not high performance. A fast boat, light and technical is expensive and perhaps not robust enough for school or club use.

Back, back, back in the day our school had Fireflies. Clunky, could just about plane on a gust day on the river but boy were they robust. Came back year after year begging for more. More to the point, they were a choice from about two or three.

Put ten people in a room and say "What boats shall we get?" and you'll get ten different answers. To be viable against the established classes you have to appeal to six out of those ten more than any other boat (including on price, or at least value!). Can you do that?

 

To your point one thing I could try would be to make all the surfaces developable to facilitate an easier and cheaper build. You know, I have been thinking quite a bit about ways to make the build cheaper and easier which may maybe include a redesign cockpit and foredeck. I would disagree that using a foam and glass sandwich construction method is too expensive - it's really not. There are also companies that will pre cut everything for you as a kit.

It seems like you are generally making an appeal for people to stick to designs that are already established. I am not going to get into a discussion about that because I don't want to be put in a position where I'm criticising others designs on a public forum. The idea behind posting my stuff was as a sort of peer review so you are welcome to evaluate and offer criticism Of MY design.