Any designers want to tackle a new build idea?

Asking about your previous knowledge is not trolling. You are posting in a forum that is mainly composed of experienced designers, builders and engineers. You call a troll anyone that questions your nonsense. Then get all offended by legitimate questions you have no response to.

 

Do some actual research on materials and designs. You will find the fundamental differences.

 

You study what the different features do for you and decide what you want. That's the designers job, learn and choose. If you don't want to pay someone to do it for you, that's the only way. You can copy what others have done, but if you don't understand why it was done a certain way you are relying on luck.

The only similarity between Wharram's sail and a modern square top is that they have four sides. Same thing as comparing a Ford A to the latest Corvette, they both have four wheels. Swapping a few components around won't transform one into the other.

The TS3 has been discussed in this forum, as have catamaran design principles.

 

Thanks, that was the question, once I know what I want, what's the next step in the design process?

I'm an amateur, what software will give me a template (lack of better description) to get started? Starting point

Little harsh saying there is only one similarity, in those sails. Wharram deserves allot more cred' then he's gotten over the years...

Different story different day...

I'll give you another, they both wrap the mast.

If you cut the top off the modern sail, add a 45 degree gaff on top you have a wharram shape...
Add the gaff 45 degree through the flag.....

See my cropped photo

Let's talk in Truth

So my point is

I'm not trying to beat the world
I will design and build a 36ft cat
That's fast (enough to be fun) safe, and built well.
The boats primary purpose is not a Miami skyline condo...it's a a very fast tent for two...sailing mostly through the Bahamas on extended trips far out

So all if I can get a wharram rig to offer an percentage of what a world class rig offers and 20% of the cost, I'm good with that...

I think I can with upgraded sail clotb over Dacron
A carbon mast which I can build

These sail shapes aren't that different

As.for.the model.A vs Corvette
You Shoulda used Ferrari

Then I' would say yes I agree, but....
The Corvette is middle ground, almost all the performance of a Ferrari (C8)
And a msrp 70k vs 395k

My sail rig and sails will be the c8 ha!
The c8 shot a huge GM warning shot over the euros car makers bows!
My sail rig and sails will shoot a warning shot over the bows of boat design forum!

I joke kinda!

 

At your skill level, you draw a nice picture of the boat above the waterline. If you can do detalied scale drawings or 3d modeling you draw the interior arrangements to fit your size preferences, if not you build a full size mockup of the living arrangements in cardboard and ducktape. Once you're satisfied you consult the Gougeon's book for some rule of thumb scantlings and start counting ounces (or grams if you're metric). After you finished with the structure you add yourself and all the equipment you want on board, including paint, engine, food, water, anchors, solar panels, etc. The resulting weight must be offset by underwater volume.
From here on its a repetitive process of determening scantlings, calculating weights, pushing volume around to match the weight distribution, modifying underwater hull shape to match performance expectations, hull appendages, and so on until you say "it's good enough".
During this process you will understand how cheap off the shelf plans really are. If you flip burgers half time after your regular job for a year you can afford a custom design. Believe me, you're going to spend more time than that designing this thing.

There is no software that will give you a template. Software does calculations faster then you can do it by hand, it's a huge advantage to be able to use it, but that's all.

It's not a "little harsh" it's milder then I should be. Yes his sails do work ok for cruising cats, but they are nothing but a slightly modernized gaff rig. You should also be aware that there is only one official supplier for his sail type and finding another sailmaker willing to build you one isn't going to be easy or cheap, especially if you start "improving" it.

Just a kind reminder of what's actually out there:

Kohler sells the full plans for his DUO 900 for 290$. That's a week of part time burger flipping. He also has other designs you might find interesting, and he does modify his designs to suit the customer. The study plans cost 15$. DUO 900 Plans https://duckworks.com/duo-900-plans/

Woods sells his Mirage plans for 1600$, that's six weeks of evening burger flipping. He also has other designs in the same price range that might interest you. Sailing Catamarans - Mirage - 11m hard chine open deck cruiser https://sailingcatamarans.com/index.php/designs-2/5-catamarans-over-40ft/179-mirage

If you think you can design better boats then these next year this time, I have a bridge for sale.

 

I have done exactly what you have suggested.


Kohlers kd860 is HIGH on the list and I have researched that one awhile

I have an email into Hughes

Woods Sango I love, too small
If he blew it up to around 32 or so, I would buy those plans asap
Group buy anyone?? Group kit cut? 32 ft Sango...would be killer



So, I have researched options


I'm still not convinced the wharram sail plan is as bad as you say..matter of fact Kohler himself likes that sail plan...told me on his forum/group
Save the bridge...ha

That KD design is still in the works with me.


The loft for the sail wharram use mostly is jeckkell
And they make good sails, and reasonable $$
From my research

I.woild love to have a set of 3di north endurance
Not in the budget, with the mast rigging required to sail it right

And I never said I could use a wharram design sail plan and equal a high performance set. I said I think I can get 60% or close with the wharram sails and set..with some small upgrading of standard materials and that's okay with me

Thanks

 

Seriously, if there is any interest in a 32-36- ft Sango design we can do a group buy..

We can also group by the foam kit cut, I'm sure Mr woods could furnish the cut files
With a new revision of the sango...

10 plans sold @ 800 per should cover it...

Who's in? Sango design

 

I don't know what you want to do with the boat, so here's my unsolicited opinion:

1. If you want to cruise the Caribbean in camping style, build the DUO 900 as is and put the best rig on it that you can afford. Add a hard top covered in solar panels over the central section and some shade netting for the sides for when at anchor.
2. If your plans are more ambitious and you want to see some far away places, take one of Woods cats and only fit the interior that is structural or you actually plan to use.

There's no point in building a boat that you don't actually use for its intended purpose. This includes a high speed craft wich you are to afraid to push to the limit.

 

Not a big fan of the duo

If I go this route, very possible, it's going to be the kd 860 or a blown up sango.

 

Not even remotely true. A modern sail will be a laminate (probably mylar) over a structure of carbon fiber and/of kevlar.

 

It is not bad. However, it would never win a race against high performance race boats from this century.

 

"polite, and if possible, informative about the subject at hand"

 

I like your approach. Getting rid of all the accoutrements will go a long way in terms of performance by avoiding the downward spiral of weight and cost. Designing a relatively efficient hull is not rocket science, like most on here make it out to be, in my novice opinion. I would read as many articles on hydrodynamics and aerodynamics as possible and it will become clear what really matters. But, I think the more complicated aspect is making your hulls and rig behave well for whatever conditions you may face, as well as structural considerations.

As far as cost, I think your estimate is feasible for hulls, structure, and rig alone, but you have to think about all the other systems and hardware. All the little things add up quick, something I learned the hard way as a handyman of 25+ years. Solar, batteries, charging, navigational equipment, accessory propulsion, appliances, dinghy(w/ motor?), fuel systems/tanks, lines, blocks, winches, safety equipment, etc, etc.

It might be good to consider just how much performance you really need, or can use safely, in most conditions. Going for good, but relatively modest performance would probably save quite a bit of money. You will already be faster than most of the "performance catamarans" out there by doing away with all the creature comforts and spaciousness, and standing headroom. Sailing well into the wind is as much about reducing aerodynamic drag as having a fancy rig. By it's nature I think the Wharram wingsail rig will not go as well upwind as some other rigs, due to the lack of control of the draft. On the other hand, taking away some of the drag and turbulence from the mast is advantageous.

I'd really take your time in the research and design process. My own design has gone through hundreds of iterations, and I'm not done yet.

PS: Some of the people on this forum can be rude and seemingly unhelpful, but veiled in their criticisms is some useful information. Don't let them get you down, keep the dream alive, but try to be as pragmatic as possible, as your life will depend on the outcome.

PS2: My personal journey through this process has led me to the conclusion that ease of handling and safety is as(or more) important as performance for overall enjoyment of the end product.