AIT Around In Ten

I see you have the same influences I have.

You desire good natural course keeping over speed performance just as I do.

I'll be following your project. Best of luck.

 

Manie, with your final design - How do you expect the boat to handle in heavy seas downwind? Wouldn't it be prone to broaching? Being so short and with the keel going all the way forward.

 

Interesting question and I am not sure of my answer.
Full keel boats are not prone to broaching, they are very slow to turn.
Lets see what sharpii2 thinks about that?
My keel is effectively 20% from the bow so I would rather describe it as a 80% full keel ???? if that makes any sense at all ???

The pic shows a true full keel and this is a very salty boat.

https://www.google.co.za/search?q=f...&bih=681#q=full keel yachts&tbm=isch&imgdii=_

 

off the net

 

Hi Manie.

I agree with most of the article, just posted.

What I'd like to add is that, while a "full keel" (which I will refer to as a "long keel", as it's a more accurate descriptive term) is less prone to broach than a short deep keel, it is also harder to get back on track if it ever does.

Short, deep keels have been successfully sailed down wind in appalling conditions. It appears that the secret is a very large rudder along with an electronic self steering system.

It also appears that the boats that got in trouble during the '79 Fastnet race had proportionately smaller rudders than the much later Around-Alone boats. This was probably to keep the whetted area down to a minimum, as the sail area was somewhat measured in the rating rule used at that time.

Your boat, IIRC, not only has a long, shallow keel, but two much shorter twin keels on either side. This makes it effectively a triple keel boat, even less likely to suddenly veer off course.

But I think the design of the sail plan has a lot to do with it.

When sailing down wind, unless you are dodging breaking waves, you want a lee helm. Such will use the sail itself as a course corrector.

 

Being in Manie's neigbourhood on past Sunday and got the first view of his AIT - actually the lines of the hull laid out full size on the floor. Quite a big little boat if I may say so.

Standing and sitting in the "boat" is actually within comfortable levels considering the size of it, and Manie told me all the dimensions and layout preferences were taken from his other boat "Fargo" he had built, fine tuned and incorporated in this design. All seems well and logical when scaled full size.

I believe Manie bought the timber for it yesterday, but haven't bumped into him collecting my plywood for the boat Im building from our supplier.

Go for it Manie and I wish you well with the project - if not mistaken this is your 6th experimental build

 

Hi Wynand,

What are you building?

 

Hi Dries,

Here some links to catch up on this . . .

- Never say never.... - - - (preface)

- My last build - 26ft traditional

- 25.6ft Gaff Cruiser under way

- Plasma Cutting; air vs Ar/N2 --> post #3​

 

Thanks Angelique, I do not keep as up-to-date as I would like to.

I try to follow what the local guys are doing, slowly the homebuilding thing is starting to gain some momentum here in South Africa. Or maybe it just feels like that because the social media allows better distribution of information.

I certainly have had something slowly ticking over for at least the last 18 years.
At the moment I am helping a friend build a powerboat (sacrilege, outrage !!!) but I thought that would distract people from Manie's attempt at a Ten, and give him time to get down to it. Certainly better than defending the decision against all the nay-sayers.

On that subject: how are things going Manie?

 

Dries I posted more here

http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-69.html#post700872

but I am good, work not as good as I would like it to be but we carry on.
My "ten" building will start very soon, all I am still busy with is experimentation on Fargo regarding sizes of the bunk, seat, and general "liveability" - measuring and taking sizes all day long!
It is soooo much easier to design when you have an active "template" on the water that you can sail and live in. On the "ten" where every millimetre of space is important it is imperative that you get it right. I am 100% happy with my "ten" design and it really is a boat that I want, the so called "one man ship"

The main reason that the sizing is important is that I am going to build the bulkheads first, they will form part of the building jig and will be almost complete as the "skin" goes on. The boat will be built upside down on a male framework.

 

During my tenure as custom steel boatbuilder over a period of about 30 years, I found this the best and easiest way to build a boat

 

With our powerboat (turns head and spits) build, the deck and frames will also go down first, upside down. Then the magic happens, and the hull is turned rightside up.

I have asked this a few times before, but let me do it again. How good is SP106 as a laminating system? I have to do some structural parts from SP106, where previously I used Ampreg 21.
The 106 datasheet is suspiciously stingy with cured system mechanical properties.....

 

All my boats were built with SP106
used it now for 7 years and it's great

BUT

you need to find out if they are still going to supply it
heard along the grapevine that it's on it's way out ?????

 

Hi Manie,

Some quick feedback:

I did the laminate with SP106 last night.
16 plies of 450 woven roving ( a heavy lay-up by most boatbuilding standards)
The job went down in a single step, very slight exotherm at the end, and the resin cured up very nicely by this morning. I will do some mech tests when I get a chance, but the fiber properties override the resin's so much that in most laminate designs I just ignore the resin's contribution.

Where did you hear that they might discontinue SP106, and what will we use instead?

 

Hello Dries, I spoke to Evan at AMT composites myself now.
SP 106 is still available for the time being BUT it has become VERY expensive and that is why they wont bring it in anymore.
Evan assures me that Ampreg 21 is as close as damit to SP 106 and they bring Ampreg 21 in huge quantities into South Africa. Ampreg 21 will now be cheaper than what SP 106 used to cost a year ago.

So the "ten" will be built with Ampreg 21
I just need to finalise the "bed" bunk size and then I'm good to go.
Every time I go out with Fargo now I'll sleep on the floor which is essentially the same size as the bed in the "ten"

Cheers