Another folding catamaran dream

[tommymonza]

I know this subject has been beat to death on this site but here we go again.

What I have to work with to begin.

1. A triple axle aluminum trailer than can fit a 10,000 28 to 33 foot boat on it.

2. I have 2 complete Hobie 16 rigs and as new mainsails and 6 to 1 mainsail blocks. A hobie mainsail is 210 sq feet and the masts measure 27 feet and the boom 9 feet.

I have a couple blade jibs and a another 150 percent jib that would all fit to the masthead of the hobie rigs

So with the 2 mainsails and a large genoa I would have around 600 sq feet for light air sailing

My reasoning between using them is that I already own some horsepower and I like the idea that 2 smaller rigs are much easier to put up and down and if I go cruising I can bring a whole extra rig in one of the hulls as a possess a total of 5 masts of varying sizes.Also you can buy a nice Hobie mainsail for about 7oo bucks and a square top Prindle 18 mainsail for about 1200 dollars.

As opposed to a single main that would be required of this size cat would require around 4 to 5 thousand with the sail and battens and cars , not to mention the sheeting requirements.

I know I will have to up the dimension of the stays and quite frankly I think I will double stay it with double hounds on the masts for safety.

So what i want in hulls as you can tell from my other threads is basically a copy of a Tornado with more freeboard , I think they will be very similar to a Silletto but narrower.i don't care to have living conditions in the hulls other than possibly a small head.

Daggerboards will be fitted as I would also like to have the rudders in cassettes such as are mentioned on this thread here http://www.boatdesign.net/forums/boat-design/rudder-drum-25041.html

some great pics of what i am talking about on the last page.

28 to 30 feet is the minimum that I can work my requirements into.

I finally found where Richard Woods stated the reason for not designing a larger folding Sango is because of the height .I hope to keep my height in the legal 12 to 13 feet when on the trailer.

So 3 feet of freeboard and a draft of a foot . A folded beam of 8.5 feet and on the water beam of 16 feet so the arms will have to swing 4 feet under the bridgedeck.The hulls will have a width of 2 feet and I need another 2 feet of clearance for the depth of the cabin footwell which will be a small pod a foot above the waterline, the clearance of the cockpit i hope to be able to drop down to 16 inches above the waterline.

Cabin will be 8 by 8 with a 8 by 5 bunk running beam wise across the front of the cabin where I need the height for bridgedeck clearance as my foredeck will be only 12 feet long.Only other thing i will have in the cabin will be a propane refrigerator freezer and a small table built into the back of the cabin side so that the bunk can be used as a seat.Headroom will be only 4 feet but there will be a large offset hatch so as to minimize the affect of this.

I also have a full dual helm and piston hydraulic steering system that i would like to utilize so that I could have inside steering also.

Outside the cockpit will be 6.5 long by 8 when folded on the trailer but 6.5 by 12 when unfolded in the water.

It will also have a hard bimini that portrudes a foot forward of the cabin house aft wall so that a dodger can be fitted and also extend 2 feet astern of the cockpit as to provide full sun shelter.Also would like for it to be fitted with full removable vinyl windows or screening . Also it will have fold out wings when the boat is folded out so to cover the whole cockpits 12 foot width.I know it is a ton of windage but this is the most important part of the boat for me, As this is where i will cook and dine and live on the boat 90 percent of the time.

Boat is to be built light and kept minimalist with a small steerable single outboard mounted on a sled.

So what do you all think?

 

[redreuben]

http://www.tennantdesign.co.nz/index.php?page=great-barrier-express

http://www.tennantdesign.co.nz/index.php?page=turissimo---9

 

[tommymonza]

Great boat but i can't sleep in a coffin sized hull and i need circulation as i will be in the southern tropics.

Most important is shade and the easy ability to fold as Woods designs are capable of doing.

 

[ALL AT SEA]

http://www.surteesmultihulls.com/9m-trailerable-catamaran.html ?

 

[tommymonza]

http://www.surteesmultihulls.com/9m-trailerable-catamaran.html ?

Nice cat but I think the Woods idea of the hulls folding under the boat is much more practical especially if you are getting into a 30 foot long hull as it lets gravity and flotation do the heavy lifting.

Also just to small.

 

[ALL AT SEA]

Would you consider a trimaran? I think that a schooner rig would propel a 9-10m tri more effectively than a cat of the same length. Although it requires more hulls to build, i think it would be a simpler proposition to trail. With two smallish rigs, and assuming quite a low weight, the amas, nor would the overall beam would need to be especially large. Folding options are varied, but i'd think something from the farrier school of thought could work. Another option could be telescoping, or dismantling? In any case it has to be easier than a folding catamaran.

 

[tommymonza]

Tri's are just too small in the 30 foot range. Granted my idea of a cat provides very little accommodations in the cabin but they are above deck where I want to be I loath the idea of sleeping down in a hull anymore.

Plus my primary living space will be under the fixed hard top bimini on the 6 by 12 foot cockpit. You just can't get that on a Tri.

I know the Bimini is going to create a lot of wind age but this is primarily a
Bahamas bound cat. and with the sleek hulls and dual rotating mast with ample sail area I think still be a nimble performer.

I have taken into consideration the load from the aft mast and being that it is not carrying the further load of a head sail, I think I can have a easily removable center beam with a dolphin striker to absorb the load.

 

[eastern motors]

Why not have a bi-plane rig if you are going to build a two masted cat? Then you could avoid a center beam, have two headsails, and keep the hulls upright on the trailer.

 

[tommymonza]

Much harder to engineer into the hulls to make them so that they can be easily set up and taken down and also would have to be freestanding which would not utilize the rigs and sails that I currently own.

 

[redreuben]

Tommy,
Condense all your ideas into one thread so people know what you want.
Give us a complete Statement Of Requirements, then the hive mind can help, you have about three threads running.

 

[tommymonza]

One thread was about hull design theories, another about building a plug and mold as opposed to building a one off ply or strip plank and another about scantlings.

The hull design theories thread is emblazoned in a full out war between a couple of members here . The other 3 threads do not apply to what I had in mind for all my ideas of why I was looking at certain hull shapes for a catamaran design nor what the boat will incorporate and how it will be used so this is the one I choose to out that info on.

Kill the other 3 if you are a mod and choose to do it.