AIT Around In Ten

sharpii2, glad that helped. Sorry for my earlier reply, it was a bit insulting.

 

Thanks, Frank.

I'm curious. What sort of rig would you put on her?

 

Not sure , an aft mast rig looks interesting, but I know nothing about them. There is a good thread here about them . A cat rig of some sort might work. I haven't thought about it much in some time. I think you could get a nice coastal sailor out of 10' . some thing for limited offshore.The problem is that it is going to be slow.

 

I agree. The jib only has been used on several occasions.

The advantages are the back shrouds end up at the widest point of the boat and the mast and all that rigging makes a handy, permanent mizzen, so the boat is far less likely to get caught in stays, when coming about.

Also the boom can be eliminated.

I used to worry about balance when shortening the single jib. Now I think the aft mast, with all its drag, will keep the balance within reason.

The only problem is a very tall mast to get decent sail area. You only have two thirds to three quarters of the deck length to play with. And I would really hate to put the tack of my only sail out on a bowsprit, on such a short boat. To get 100 sf of sail on a 7.5 ft deck you need 26.67 ft of mast, not including deck clearance (which can be minimal w/o a boom) and bury, within the hull.

As ridiculous as it may seem, a Bermudan cutter rig may make a lot of sense for this type of boat. Here's one, I sketched a few years ago, with the mast quite far aft. The mainsail ends up being so small, it actually acts like a mizzen. (see attachment). It would be struck during most of the voyage. Its lost area would be compensated with a larger outer jib.

Of course, there would be rigging cables everywhere, but the mast would be well supported and likely to still be with the boat, if the boat is ever rolled.

(This rig was drawn for a different boat.)

 

Would an A-frame mast be possible on the MICRO 10 ? ?

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( specs from above link are also in post #57 )​

 

Sure it would.
Nice design by Paul Fisher, and ready to go.

 

I agree. The sturdier the better. The "A" frame may cost a little more in weight, but may be more rugged than a team of spreaders, with all kinds of cables and connectors.

 

If one uses the same tube as the A-frame for the forestay, instead of a wire fore and back stay, it would produce the sturdiest 'mast' in the world I think, but it would add windage too, especially aloft, so it might make the boat less weatherly.

So, three tall windsurf masts in total . . ? ?​

P.S. - Aircraft engineers stopped wire rigging long time ago, their chosen path would call for a free standing mast and not the construction I've described above . .

- - click pic to enlarge

Example of the complexity and the many points of possible failure of wire rigging on planes, same goes for boats I think.

Info about this plane ---> Royal Aircraft Factory S.E.5 ---> S.E.5a​

 

I like the idea of a fore and aft "A" frame mast. With the forward part holding the luff reasonably straight, high back stay tensions are no longer needed. I fact the back stays themselves can be eliminated.

The main mast (the vertical aft portion) can then be stepped right at the transom.

A system of shrouds could than add athwart ship support to the system.

I imagine two or three on each side, connected to a common point on deck.

The lower shrouds, having a more favorable angle and being shorter, will give the mast more rigid support in that region. The higher shrouds will give less rigid support, allowing the whole system to be more resilient than a standard mast head set up.

This resilience will have far less effect on the set of the jib only sail, with the fore mast at its luff, than it would with a fore stay there.

The advantage I see, with such a set up, is that , if the boat is rolled, the top of the mast can absorb some of the energy, by flexing, but its range of movement would still be limited by the higher shroud. This might keep the mast from breaking above the lower shrouds, but avoid a huge, sudden shock load to the chain plates.

 

Well Manie, you have me interested in this whole AIT thing now. long time follow of your micro cruiser and after talking with Serge Testa through email, you have my design juices flowing.

mark me down as a hopeful in this endeavor.

will post some picts of my idea for a design in the coming days.

best I can see though, based on all that is available, for this size boat, most of us will come up with very similar shapes. when we try to stuff that much stuff into a capsule (and let's face it, that is what we will be doing) rocket us off, if even at a snails pace, there is not many options.

 

This original rule of AIT: "•The race is restricted to monohulls (No catamarans or trimarans). "

What do you think of it? Any idea on the motivation behind it? Would a 10x10 feet catamaran with some level of ballast (100+ days worth of food & water) be too dangerous for blue-water sailing by default? capsize, pitchpooling etc without any chance to recover.. I imagine that the speed potential could be improved significantly with a catamaran. Perhaps also reducing the sense of confinement. Two hulls, 3x1 meter each, 1 meter apart, with a fairly big top/platform structure and two free-standing masts with furling around mast or boom..

 

MoeJoe,

for a cat to be able to support the amount of weight to keep us supplied, you would be sailing two very fat hulls and hence lose the strength a cat has, speed. to get speed, you need narrow hulls, and to get load carrying capability, you need length. so for a 10' boat, you would need two hulls at least 3' wide and then you run into wave making issues, etc...

for a 10' boat, only a monohull is going to work in my opinion.

 

Actually there are at least two alternative general strategies:

1.) The heavy hauler. To carry a lot of gear and travel great distances at a time. Such would require a boat that is quite burdensome and very strong. YANKEE GIRL is a great example of a good boat for that strategy. Because she had such a deep "V" bottom, she needed almost no external keel for lee way prevention. And because of her bottom type, she was able to carry heavier stores and gear low enough to need little if any ballast.

2.) The short hopper. To be lighter and faster, but have much shorter range. The idea is to make as many stops a necessary, to keep each hop two thousand miles or less. Such is going to require a boat that is far less burdensome, carries more SA for its weight, probably has a good deal of self steering gear on board, and may have a water maker. The boat for this strategy is far more likely to have a deep fin keel with self righting ballast.

The short hopper is far more likely to have a larger, more vulnerable rig than the heavy hauler, as it has a better chance of avoiding bad weather. It can wait at one of its many stops for more ideal conditions for its next hop.

The heavy hauler, though slower, may actually come out ahead, as it will make fewer stops. Kind of like the tortoise and the hare.

The heavy hauler is more likely to have a shorter, stubbier rig, that can withstand capsizes and pitch polings.

The heavy hauler is likely to average 40 to 50 mile days. The short hopper may do as well as to average 60 to 70 mile days (both types are certain to have D/Ls north of 500, so are not likely to exceed hall speed)

At the AIT web site, I saw excellent proposals for both strategies.

My "Football" proposal tries to split the difference. It will make short hops when practical and longer ones when necessary. She has a fin keel, but it's long to insure better directional stability and greater comfort at sea.

 

Hi Wescraft, I have now done dozens of drawings and my cad files are like a zoo, but I always come back to the same thing. Like you said there is only so much that you can do with a 3m boat. Like sharpii2 said the 2 main differences would be "light" or "heavy"
I have gone for "heavy" because the main ballast is 200 liters of water under the bunk. This means that I could go light for weekends and trailering but the design is around long hauls of at least a 100 days.
My "Fargo" is 95% finished and just about everything is "built" or made and all I have to do is finishing the parts off. What is an absolute pain is how much time the little things take.

My grand plan is most definitely to start my "ten" as soon as I have Fargo finished. I am very keen on building a "capsule" Because there is no commercial value for a 3m heavy displacement full keel one man yacht, I just feel that there is not enough data available and the big boys that always come with the bigger is better / safer story have never been on a small cruiser because it does not exist - so how can they say it's bad. I have been in some nasty storms and I am 100% fine ok, I even slept well. The others took a hiding of note, most of the wife's and girlfriends will never go near the water again. Here are some interesting pics.

Give me a small solid boat with a warm dry bed anyday!

 

One very important aspect is the fact that the cabin must be divided in two sections, like what Sven is doing. When the hatch is open to the elements the bunk / bed area MUST be sealed of the stay dry. I don't have this at the moment and it is a pain.