I haven't decided what to actually build yet, but it must be some sort of sailboat which size is limited to that which I can carry easily in my car.. which is something I haven't put the details of in the planning yet because I haven't taken the measurements needed.
I would say the max. size would be at least 4.5 foot bow to stern.. maybe more.. I will have to check and report back the actual max size it can be. I also thought about 6.375 ft., 7ft or 8.5ft.
Why I want to do this project is because when I was a young boy, my grandfather helped build me a line control sailboat made from a few pieces of scrounged marine plywood and a 2x4 for a keel (and a steel plate attached to the bottom of the keel) for a weight. I used a piece of string/yarn or fishing line to control the boat from ashore, but mainly letting it go whever it wanted to. The rudder was on a dowel, and a piece of sheet steel. This boat was not more than a foot long but had a working sail, mast and boom. I would set the rudder angle, set the boat on the water and then give the craft a nudge to get it going. Once I did this, there was no way I could change the rudder angle, or the trim for the sails, except to haul it back in and wind up or letting out the yarn I used for rigging the sails. I used a piece of garbage bag for a sail, but now I want to use either a real (lightweight) sail canvas or sail material or some other suitable outdoor material.
I'd like to make this happen again, but I want to make an actual sailboat hull in a larger size.
The first thing of all it must have at least 1 sail, have a shore controlled mechanism for changing the rigging, and rudder angle/steering, and anything else I can come up with.
It could very well have motors, transmitters, servos, etc to do all this work too.. even a working bilge pump.
It needs to be able to right itself if tipped over with the appropriate keel weight.
I'm not an engineer or a designer, so I don't know the actual #'s to make this happen.. or what type of design I should use.
It also needs to be able to use standard parts in this scale, have cleats, lighting, winches, etc. Extra functions like a horn, antenna, water depth measurement system, etc.
The other thing is that the mast & boom must be able to be dismantled for easy transportation...
If I finish this project I will build a simiar sized twin engine / twin prop scale pleasure craft.
I am into RC model aircraft and what you are thinking of of is not unheard of. Do some searching on the net to see what is out there and how it is built and where the parts are available. You could either go with a kit or draw up your own by scaling up a 3 view. On the last couple I did the scale bit and started with a 3 view and got the actual measurements from the full scale and designed from there.
If you design your own, look for different ways of construction especially if it is from full scale. You are just going smaller so everything is relevent.
If you have any questions I may be able to help.
John
iirc there were a some sailboat construction articles in model engineer in the 50's or 60's maybe. A popular technique was/is 'bread 'n butter' construction, sandwiching pine cut out the to approximately the interior and exterior contour line of the hull and carving to shape. I would think many plans have been done over the years - there's enough to hull design to leave it to those that know.
its extremely rare for a keel boat (fixed, lead keel) to capsize, the more they heel over, the less sale is exposed to the wind and therefor there is less heeling force - keel brings them back.
I'd make it water tight to protect the electronics then no worry about the bilge. The majority of designs would two sails, one mast, typical of the majority of sail boats you see today. This is what you want IMO, single boats are less efficient.
IMO you want rudder, jib sheet and main sheet controls, can't see why you'd need more. problem is those controls require some thought - you'll need a torque to adjust the sails under tension, but ideally you want it fast (the jib). also, sail boats should turn quickly and with minimal forward speed - this means a BIG rudder. The rudder control would need to be faster and more powerfull than that for a stink pot (oopps meant power boat ). all this probably means you'd need a largish, maybe motorcycle sized battery to power it all.
for hardware, you might make it yourself, i don't know how much is available commercially to scale. transport is an issue, might have to buy the suburban. masts are easily detachable - their strength comes from the stays (wire guys) and in full size practice are a bit of a loose fit through the hull.
you got me going on this because I've often thought of this sort of project. first thing is to decide on the objectives - ie perfect scale model or performance racer then start hunting down designs.
Thanks for your input. I'm searching the public library and the web for designs in that size class. A pump would be just a thought.
I have a commercial/industrial battery supplier available for any batteries I need, even RC type NiCad, etc.
For the construction of the hull, I like your idea.. would it be possible to machine the int & ext contours?
As for a powerboat, my dad liked the Reinell (Sp?) designs. I might think about doing one of those too once I am finished with this.. and maybe have a little fun with a cool prop!
This is one of the reasons I wanted to learn SolidWorks 2006.
I don't see any reason why you can't machine the hull out of solid but would make a reccomendation that you do it in foam first. Hate to see a good piece of wood get machined and find it is wrong. The other thing you could do with the foam after is cover it with epoxy and glass. With this method you at least would have less chance of sinking and also very strong.
John
Not sure of what you mean by wax molds unless cutting it out of wax for the hull. I like the idea of wood in a boat as the wood grain looks nice when finished. If you build it out of wood you can also use epoxy(clear) and get the same effect only stronger.
I make my ac plug's out of foam for molding and the finish of the plug is what you get for the final (outside) result. If you go this way I can give you my method which is common with a lot of guy's.
John
John, I've done a built up model boat hull in mahogany, made the extreme effort for nice joinery, scraped finish (sandpaper never touched the wood) etc, worth the effort. ended up applying fiber glass cloth(finest mesh) with epoxy, several coats with sanding (the epoxy) and topped off with urethane finish for UV protection as the epoxy will yellow. its very strong and the wood just glistens, but I'm thinking of taking it down again, (thats a lot work) because surface finish looks too 'thick' and, kind of, well, plastic which of course it is. I really like the idea of the fiberglass cloth, it gives the hull tremendous strength, but I've yet to figure out what would rival a rubbed down varnish finish that can be used with the cloth, the epoxy just doesn't look as nice. I'm open to new ideas, any specifics on your approach?
With your epoxy I am not sure what you are using but I would check with http://www.westsystem.com
They have epoxy that is for covering boats and in there brochure it mentions ceder strip canoes. I use 5/8oz. cloth for my wings which is what you would want for protection. It requires very little epoxy to saturate and I use 2 coats. The first coat I dribble over the glass and saturate the cloth then scrape(old credit card preferably the wife's) as much as I can off. I then let set overnight then sand the bumps off without getting into the cloth and clean. Then I apply a thin wet coat to just fill the weave and make it smooth. Then let set for a couple of days before final finish. I wet sand and my final finish is with 600. Lots of work but start with 220 wet and work up. Then you can apply your top coat of urethane or what you want. I spray the auto clear coat with a touch up gun.(auto) Using a brush to me puts it on to heavy as I like to stay as lite as possible.
If you have used heavier cloth then this, it is possible where your thick finish would result from. I know the balsa grain really comes out with the thin cloth. It is more like wrapping with saran wrap than wax paper.(that's a joke)
Try pm West and get there opinion as they are in business for this and it is great product.
John
I should add that epoxy gives off a wax that will show up in a haze when curing. Also the more patience you have to let it cure the better. It goes hard fast but it is curing for a long time. Somebody mentioned to me it never finish's hardening but West could tell you.
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). all this probably means you'd need a largish, maybe motorcycle sized battery to power it all.
